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Management of Helicobacter pylori infection—the Maastricht V/Florence Consensus Report

Authors:
  • Hospital Universitario de La Princesa, Instituto de Investigación Sanitaria Princesa (IIS-IP), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD)

Abstract

Important progress has been made in the management of Helicobacter pylori infection and in this fifth edition of the Maastricht Consensus Report, key aspects related to the clinical role of H. pylori were re-evaluated in 2015. In the Maastricht V/Florence Consensus Conference, 43 experts from 24 countries examined new data related to H. pylori in five subdivided workshops: (1) Indications/Associations, (2) Diagnosis, (3) Treatment, (4) Prevention/Public Health, (5) H. pylori and the Gastric Microbiota. The results of the individual workshops were presented to a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in the various clinical scenarios.
Management of Helicobacter pylori infectionthe
Maastricht V/Florence Consensus Report
P Malfertheiner,
1
F Megraud,
2
CAOMorain,
3
J P Gisbert,
4,5
E J Kuipers,
6
A T Axon,
7
F Bazzoli,
8
A Gasbarrini,
9
J Atherton,
10
D Y Graham,
11
R Hunt,
12,13
P Moayyedi,
14
T Rokkas,
15
M Rugge,
16
M Selgrad,
17
S Suerbaum,
18
K Sugano,
19
E M El-Omar,
20
on behalf of the European Helicobacter and Microbiota Study Group and Consensus panel
Additional material is
published online only. To view
please visit the journal online
(http://dx.doi.org/10.1136/
gutjnl-2016-312288).
For numbered afliations see
end of article.
Correspondence to
Professor P Malfertheiner,
University of Magdeburg,
Department of
Gastroenterology, Hepatology
and Infectious Diseases,
Leipziger Str. 44, Magdeburg
39120, Germany; peter.
malfertheiner@med.ovgu.de
Received 19 May 2016
Accepted 9 August 2016
To cite: Malfertheiner P,
Megraud F, OMorain CA,
et al.Gut Published Online
First: [please include Day
Month Year] doi:10.1136/
gutjnl-2016-312288
ABSTRACT
Important progress has been made in the management
of Helicobacter pylori infection and in this fth edition of
the Maastricht Consensus Report, key aspects related to
the clinical role of H. pylori were re-evaluated in 2015.
In the Maastricht V/Florence Consensus Conference, 43
experts from 24 countries examined new data related to
H. pylori in ve subdivided workshops: (1) Indications/
Associations, (2) Diagnosis, (3) Treatment, (4)
Prevention/Public Health, (5) H. pylori and the Gastric
Microbiota. The results of the individual workshops were
presented to a nal consensus voting that included all
participants. Recommendations are provided on the basis
of the best available evidence and relevance to the
management of H. pylori infection in the various clinical
scenarios.
INTRODUCTION
Nearly 4 years after publication of the Maastricht
IV/Florence Consensus Report
1
the content has
been updated by maintaining the traditional inter-
val considered appropriate for capturing progress
in the eld of Helicobacter pylori related clinical
issues and adapting the management to current
demands.
Among the challenges, the increasing H. pylori
resistance to previously efcacious antibiotic regi-
mens is of great concern and requires modication
of therapeutic strategies. Furthermore, new studies
have been conducted to demonstrate the feasibility
and efcacy of primary and secondary gastric
cancer prevention. A recent important evolution
has taken place by the publication of the Kyoto
consensus report.
2
Key outcomes of this consensus
report include the designation of H. pylori gastritis
as an infectious disease with the recommendation
of treatment of all H. pylori infected subjects. This
represents a paradigm shift, as the indication for
treatment is no longer reserved for patients with
clinical manifestations of the infection. In the same
consensus, H. pylori gastritis with dyspeptic symp-
toms was designated as a specic entity outside the
umbrelladenition of functional dyspepsia. Both
these aspects have been carefully re-examined. The
role of H. pylori infection has also been assessed
with the perspective of potential interactions with
other microbiota in the upper and lower digestive
system, as the gut microbiome has emerged as an
essential player in human health and disease. A
comprehensive and updated overview on the
complexity of gastric functions in health and
disease has recently addressed this issue.
3
The aim of this report is to serve as a
state-of-the-art guide for the management of
H. pylori infection and related clinical manifesta-
tions and also as an inspiration for new clinical
research in the area.
In the Maastricht V/Florence Consensus Report
43 experts from 24 countries convened for 2 days
for a face-to-face meeting after having been actively
involved in a previously started Delphi process as
described below.
The working groups were set up according to the
following topics:
Working group 1: Indications/Associations
Working group 2: Diagnosis
Working group 3: Treatment
Working group 4: Prevention/Public Health
Working group 5: H. pylori and the Gastric
Microbiota
METHODOLOGY
The evidence-based Delphi process developed con-
sensus statements following proposals by desig-
nated coordinators. The process allowed individual
feedback and changes of views during the process
regulated by the coordinators and the consensus
chair.
The principal steps in the process were: (a) selec-
tion of the consensus group; (b) identication of
areas of clinical importance; (c) systematic literature
reviews to identify evidence to support each state-
ment, draft statements and discussions supported
by the evidence specic to each statement.
Two rounds of voting were conducted.
The delegation was asked to choose one of the fol-
lowing ratings for each statement:
agree strongly
agree with reservation
undecided
disagree or
disagree strongly.
When no strong agreement was reached, the
statement was rephrased and the vote was repeated.
Evidence-based discussions with key references
were provided for each statement on which partici-
pants voted. Consensus had to be reached by 80%
of respondents who (a) strongly agreed or (b)
agreed with reservation.
The level of evidence and strength of the recom-
mendations were completed only after the individ-
ual working group meetings. Based on the type of
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studies, evidence levels and grade of recommendation were
either based on the system used in the previous consensus
reports (see online supplementary appendix)
1
or, if statements
were suitable for grade assessment, based on so called PICO
questions (PICO: population, intervention, comparator,
outcome) they have been graded accordingly.
4
The Face to Face meeting was held in 89 October 2015 and
reviewed the statements in individual working groups rst
which were then presented to all delegates for nal voting.
Statements that have passed the 80% consensus threshold are
reported in here.
WORKING GROUP 1: INDICATIONS/ASSOCIATIONS
Statement 1: H. pylori gastritis is an infectious disease irrespective of symptoms
and complications.
Level of evidence: 1B Grade of recommendation: A
H. pylori is a human pathogen that is transmitted from
human to human, and causes chronic active gastritis in all colo-
nised subjects. This can lead to peptic ulcer disease, atrophic
gastritis, gastric adenocarcinoma, and MALT (mucosa-associated
lymphoid tissue) lymphoma. H. pylori eradication cures gastritis
and can alter the progression to long-term complications, or
recurrence of disease. For these reasons, H. pylori is considered
an infectious disease irrespective of an individuals symptoms
and stage of disease.
2
Statement 2: A test-and-treat strategy is appropriate for uninvestigated dyspepsia.
This approach is subject to regional H. pylori prevalence and cost-benefit
considerations. It is not applicable to patients with alarm symptoms or older
patients.
Level of evidence: high Grade of recommendation: strong
In young patients with uninvestigated dyspepsia the
test-and-treatstrategy with non-invasive tests is preferred
rather than prescribing proton pump inhibitor (PPI) or direct
oesophago-gastro-duodenoscopy (OGD), avoiding cost, incon-
venience and discomfort.
56
The rationale for guidelines recommending a test-and-treat
over an endoscope-and-treatpolicy is based on the outcome of
ve randomised controlled trials (RCTs).
710
These ve studies
were included in a meta-analysis
6
and four were included in a
Cochrane report.
11
There was a small but signicant benet for
the endoscope-and-treatstrategy in terms of improvement of
symptoms and patient satisfaction.
6
But this was negated by a
cost saving of US$389 per patient in the test-and-treat arm. This
economic benet was achieved in the short- and long-term by
reducing the number of endoscopies.
Based on economic evaluations, some guidelines advocate
initial empiric treatment with a PPI if the H. pylori prevalence
in a population is below 20%. These economic analyses may
not apply to all countries. Screening for H. pylori may not be
appropriate when the population prevalence of H. pylori
decreases to 10% as this may result in a signicant proportion
of false positives, leading to unnecessary treatments.
12
This is
more likely to occur with the less sensitive and specic serology
tests than with the urea breath test (UBT).
There is a close correlation between the prevalence of
H. pylori and the incidence of its related diseases, including
peptic ulcer and gastric cancer. This implies that in an environ-
ment with low H. pylori prevalence, the chance of a positive
test as well as H. pylori-related disease are both low. A lower
prevalence of H. pylori in the population increases the chance
that a positive H. pylori serology test is false. This implies that
the positive predictive value of the test declines with decreasing
H. pylori prevalence. In such a population, a chance of
non-H. pylori-related pathology is higher than the risk of
H. pylori-related disease. The use of an endoscope and treat
approach in regions of low H. pylori prevalence may be consid-
ered as it may offer additional benet by ruling out signicant
oesophageal pathology.
When alarm symptoms are presentweight loss, dysphagia,
overt gastrointestinal (GI) bleeding, abdominal mass or iron
deciency anemiaan OGD is needed.
13
When the risk of
gastric cancer is high, the test-and-treatstrategy is not recom-
mended, and OGD is preferred, especially in older adults in
whom non-invasive tests are less accurate.
14
The threshold
varies between regions depending on the age of the subject with
gastric cancer.
Statement 3: An endoscopy-based strategy should be considered in patients with
dyspeptic symptoms, particularly in low prevalence H. pylori populations.
Level of evidence: very low Grade of recommendation: weak
Endoscopy should include visualisation of the whole upper
GI tractthat is, oesophagus, cardia, fundus in retroexion,
corpus, antrum, duodenal bulb, and descending duodenumin
order to detect any pathology and to biopsy any visible lesion.
Biopsies according to standardised protocols need to be taken.
If endoscopy is performed it should be quality assured, and in
countries with low H. pylori prevalence, it rules out signicant
oesophageal pathologies.
Statement 4:H. pylori gastritis may increase or decrease acid secretion.
Treatment may reverse or partially reverse these effects.
Level of evidence: high Grade of recommendation: high
People with non-atrophic antral-predominant gastritis have
high stimulated acid production due to decreased somatostatin in
the antrum, and increased gastrin levels compared with non-
infected controls. Clinically, duodenal ulcer and non-ulcer dys-
pepsia are common in this group.
1517
In contrast, people with
atrophic gastritis (involving both antrum and corpus mucosa)
have impaired acid production. This phenotype is associated with
gastric proximal ulcers, more advanced precancerous lesions, and
with an increased risk for gastric cancer.
18 19
In both of these pat-
terns of gastritis, treatment of H. pylori resolves the gastritis and
leads to partial correction of the high or low acid state. Such
reversal is not noted in cases within extensive atrophic
changes.
2023
The increased acid secretion after treatment has
been described as worsening aspects of gastro-oesophageal reux
disease (GORD) in people who already have a weak lower
oesophageal sphincter.
2328
However, in most populations, the
changes in acid production after H. pylori treatment have no
proven clinical relevance and should not be used as an argument
to treat or not to treat H. pylori.
Statement 5:H. pylori gastritis is a distinct entity and causes dyspeptic symptoms
in some patients. H. pylori eradication produces long-term relief of dyspepsia in
about 10% of patients in comparison to placebo or acid suppression therapy.
Level of evidence: moderate Grade of recommendation: strong
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The latest WHO ICD-11βversion under development and
the Kyoto Global Consensus of H. pylori gastritis
2
recommend
that the classication of gastritis is based on causative factors,
which includes (a) H. pylori-induced, (b) drug-induced, and (c)
autoimmune gastritis. H. pylori gastritis is a distinct cause of
dyspepsia and is therefore an organic disease.
29 30
This is in
contradiction to the Rome III consensus that considered
H. pylori-associated dyspepsia to be functional dyspepsia.
31
Many H. pylori-positive subjects do not have symptoms, but
in a subset of patients H. pylori is the cause of symptoms. Acute
iatrogenic or self-administered infection with H. pylori can
induce acute dyspeptic symptoms.
32 33
However, while persist-
ent colonisation virtually always leads to chronic gastritis, in the
majority of subjects the symptoms are transient.
Epidemiological studies show an association between
H. pylori infection and dyspeptic symptoms,
3437
although
some point to other factors as being more important. The most
convincing evidence showing a causal link, however, comes
from H. pylori eradication studies in infected patients with unin-
vestigated or functional dyspepsia.
11 3840
In these studies,
eradication is associated with a small but statistically signicant
benet for symptom control over no eradication (estimated
number needed to treat (NNT)=14). The symptomatic gain
takes at least 6 months to become signicant over no eradica-
tion, and this has been attributed to the time it takes for gastritis
to recover.
38 40
Sustained symptom abolition or improvement provides the
rationale for considering H. pylori gastritis as a distinct disease
entity causing dyspeptic symptoms.
Statement 6:H. pylori gastritis has to be excluded before a reliable diagnosis of
functional dyspepsia can be made.
Level of evidence: high Grade of recommendation: high
Dyspeptic symptoms are very common, and can occur as a
result of a range of different upper GI conditions. When a dys-
peptic patient has no diagnostic work-up, the condition is classi-
ed as non-investigated dyspepsia. If patients have an
endoscopic work-up, this may yield different diagnoses, including
GORD or peptic ulcer. Patients with dyspepsia but without endo-
scopic lesions are classied as having functional dyspepsia.
H. pylori gastritis is an infectious disease that leads to chronic
active gastritis of varying severity in all infected subjects.
41
Cure
of H. pylori infection heals the inamed gastric mucosa.
34244
For these reasons, a diagnosis of true functionaldyspepsia
can only be made in the absence of H. pylori. This can be either
by primary exclusion of H. pylori gastritis, or conrmation of
successful eradication.
Statement 7: The use of aspirin and non-steroidal anti-inflammatory drugs
(NSAIDs) increases the risk of ulcer disease in H. pylori infected subjects.
Anticoagulants (aspirin, coumarines, new oral anticoagulants) increase the risk of
bleeding in patients with peptic ulcer.
Level of evidence: high Grade of recommendation: strong
NSAIDs, aspirin, and H. pylori infection are independent risk
factors for peptic ulcer and peptic ulcer complications.
45 46
A
meta-analysis showed that NSAIDs use increases the risk of
peptic ulcer in H. pylori-infected patients.
45
A recent epidemio-
logical study has shown that H. pylori infection and NSAIDs
use have additive effects on the risk of peptic ulcer bleeding.
46
Another meta-analysis
47
of ve randomised clinical trials and
additional studies reported more recently
48
have shown that
H. pylori eradication is associated with a reduced incidence of
peptic ulcer in new users but not in chronic users. No evidence
is available for the effect of H. pylori eradication in coxib users.
The effect of H. pylori infection on the risk of peptic ulcer or
peptic ulcer bleeding in low-dose aspirin (acetylsalicylic acid,
ASA) users is more controversial. Although H. pylori eradication
has been shown to reduce peptic ulcer bleeding in ASA users,
49
51
a more recent meta-analysis pointed out that the evidence
was not enough to conclude that this infection was a risk factor
for peptic ulcer bleeding in ASA users.
52
Furthermore, a recent
epidemiological study found neither an additive nor a potentiat-
ing effect between ASA and H. pylori infection, although both
were independent risk factors for peptic ulcer bleeding.
46
New evidence shows that therapy with non-aspirin antiplate-
let agents or anticoagulants also increases the risk of peptic
ulcer bleeding.
53
Since H. pylori infection is an independent risk factor for
peptic ulcer bleeding, it seems reasonable to assume that
H. pylori-infected individuals may be exposed to a greater risk
for ulcer bleeding with these non-ulcerogenic compounds than
non-infected individuals.
Statement 8: Testing for H. pylori should be performed in aspirin and NSAIDs
users with a history of peptic ulcer.
Level of evidence: moderate Grade of recommendation: high
NSAIDs, aspirin, and H. pylori infection are independent risk
factors for peptic ulcer and peptic ulcer complications.
45 46
Patients with a history of peptic ulcer or peptic ulcer bleeding
are at the highest risk of upper GI bleeding if treated with
NSAIDs, coxibs or aspirin.
46 54
A few clinical trials
49 55 56
and
one observational study,
50
conducted in these high risk patients
of Chinese origin, have shown that H. pylori eradication
reduces but does not eliminate that risk, and that PPI co-therapy
seems still necessary to reduce further the risk of upper GI
bleeding. Therefore, PPI treatment is mandatory for those who
receive NSAIDs, coxibs or even low-dose aspirin after a peptic
ulcer bleeding event and H. pylori eradication if tested positive
for the infection.
49 55 56
Statement 9: Long-term treatment with PPIs alters the topography of H. pylori
gastritis. Eradication of H. pylori heals gastritis in long-term PPI users.
Level of evidence: low Grade of recommendation: strong
The patterns of H. pylori colonisation and associated gastritis
depend on the level of acid output. In situations with normal to
increased acid output, bacterial colonisation and gastritis are
predominantly conned to the gastric antrum. In situations of
decreased acid output, bacterial colonisation and gastritis also
affect the gastric body, leading to corpus-predominant pan-
gastritis. This pattern is solely related to the level of acid output,
irrespective of the underlying cause such as gland loss, vagot-
omy, or profound acid suppressive therapy. In case of the latter,
the conversion from antral-predominant gastritis to
corpus-predominant pan-gastritis occurs within days to weeks
after initiation of therapy,
57
and remains throughout the dur-
ation of treatment.
5860
Eradication of H. pylori cures gastritis
irrespective of the continuation of acid suppressive drugs.
42 61
At a population level, H. pylori and GORD are negatively
associated, and this is most marked for cytotoxin-associated
gene product (CagA)-positive strains of H. pylori.
62
A review of
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26 studies showed a rate of H. pylori infection in patients with
GORD of 39% compared with 50% in controls.
63
Similarly, the
sequelae of GORD, such as Barretts oesophagus and oesopha-
geal adenocarcinoma, are also less common in infected indivi-
duals.
64
However, eradication of H. pylori in populations of
infected patients, on average, neither causes nor exacerbates
GORD.
6568
Therefore the presence of GORD should not dis-
suade practitioners from H. pylori eradication treatment where
indicated. In addition, the long-term efcacy of PPI mainten-
ance treatment for GORD is not inuenced by H. pylori
status.
42 69
An interesting phenomenon has been observed
whereby some H. pylori-positive patients may develop a
sudden-onset, transient epigastric pain shortly after the start of
PPI treatment for reux,
70
but this again should not affect deci-
sions on management, and more studies are needed to conrm
and explore this phenomenon.
Statement 10: There is evidence linking H. pylori to unexplained iron deficiency
anaemia (IDA), idiopathic thrombocytopenic purpura (ITP), and vitamin B12
deficiency. In these disorders, H. pylori should be sought and eradicated.
Level of evidence: very low Grade of recommendation: weak
The association of H. pylori with unexplained IDA has been
conclusively proven in adult and paediatric populations.
71
Recent meta-analyses have shown that H. pylori eradication
improves anaemia and increases haemoglobin levels, in particu-
lar in those with moderate to severe anaemia.
72 73
Indeed recent
national guidelines on the management of IDA recommend
eradication of H. pylori, where present, in patients with recur-
rent IDA with normal OGD and colonoscopy results.
74
For a dults w ith ITP, recent studies have shown increased plate-
let counts in some patients treated for H. pylori and increased
response rates in countries with a high prevalence of H. pylori
infection in the background population.
75
ITP patients with atro-
phic gastritis are reportedly more likely to respond to H. pylori
eradication therapy.
5
Consensus guidelines on the management of
ITP recommend eradication therapy in ITP patients who are
H. pylori positive (based on UBTs, stool antigen tests (SATs) or
endoscopic tests) and that H. pylori screening should be consid-
ered in patients with ITP in whom eradiation therapy would be
used if testing is positive.
76 77
These guidelines currently recom-
mend against routine testing for H. pylori in children with
chronic ITP based on conicting reports in the literature,
although there are some studies that suggest that H. pylori eradi-
cation may prove effective in paediatric ITP patients.
78
Studies have shown a link between chronic H. pylori infection
and malabsorption of vitamins, including deciencies in the
absorption of vitamin B12, which results in the accumulation of
serum homocysteine.
79
Statement 11:H. pylori has been positively and negatively associated with a
number of other extra-gastroduodenal conditions. The causality of these
associations is not proven.
Level of evidence: moderate Grade of recommendation: moderate
In addition, H. pylori infection and CagA positivity have been
associated with atherosclerosis.
8083
Interesting associations have
also been noted between H. pylori and several neurological con-
ditions, including stroke, Alzheimers disease, and idiopathic
Parkinsons disease.
8487
However, these associations are not
sufcient to make a clear causal or therapeutic link. Inverse
associations have been described between the declining rates of
H. pylori infection in some countries and the increasing preva-
lence of obesity and asthma.
88
In a large, population-based
Japanese study H. pylori eradication was associated with a sub-
sequent signicant increase in body mass index.
89
A range of studies have reported negative associations
between H. pylori colonisation and asthma and other atopic
conditions (see online supplementary table S1 and S2).
Statement 12:H. pylori eradication is the first-line treatment for localised stage
gastric MALToma.
Level of evidence: moderate Grade of recommendation: strong
Localised stage gastric MALToma are strongly associated with
H. pylori infection. In the early (Lugano I/II) stage low-grade
MALT lymphoma can be cured by H. pylori eradication in 60
80% of cases.
90
When the lymphoma contains a t (11,18) trans-
location, however, H. pylori eradication is usually ineffective
90
and these patients need adjunctive and alternative treatments.
Patients with gastric MALToma are at increased risk for develop-
ment of gastric adenocarcinoma,
91
with the majority having
signs of premalignant gastric lesions.
92
All patients should be
followed up intensively after H. pylori treatment
93
and given
alternative treatments (chemotherapy or radiotherapy) if the
lymphoma fails to respond or progresses.
WORKING GROUP 2: DIAGNOSIS
Statement 1: UBT is the most investigated and best recommended non-invasive
test in the context of a test-and-treat strategy. Monoclonal SAT can also be
used. Serological tests can be used only after validation. Rapid (office) serology
tests using whole blood should be avoided in this regard.
Level of evidence: 2a Grade of recommendation: B
The
13
C-UBT is the best approach to the diagnosis of
H. pylori infection, with high sensitivity and specicity, and
excellent performances.
9496
Out of 12 RCTs comparing the
test-and-treatstrategy to OGD or PPI therapy, eight (66%)
were performed with UBT, four (33%) with serology, and none
with SAT.
14
C UBT has also been proposed because of its lower cost,
but as it exposes patients to radiation it cannot be used in chil-
dren and pregnant women.
97
SAT may be less acceptable in
some societies but also has a high sensitivity and specicity, pro-
vided a monoclonal antibody-based ELISA is used.
98
There is
no RCT comparing the test-and-treatstrategy with OGD or
PPI therapy that used SAT.
94
Some serology tests have high sensitivity and specicity,
99 100
but these tests may perform differently in different geographic
locations according to the antigenic composition of the circulat-
ing strains. Thus, only locally validated tests should be used.
This can be done by testing the serum of patients known to be
H. pylori positive by invasive methods (histology, culture, PCR).
As for other tests, predictive values are highly dependent on the
prevalence of the infection.
Rapid (ofceor near-patient) serological tests using whole
blood could facilitate application of the test-and-treat strategy in
general practice. However, these tests have not yet been
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approved, as their sensitivities and specicities observed to date
have generally been disappointing.
101
Statement 2: PPI should be discontinued at least 2 weeks before testing for
H. pylori infection. Antibiotics and bismuth compounds should be discontinued at
least 4 weeks before the test.
Level of evidence: 2b Grade of recommendation: B
PPIs have an anti-H. pylori activity and decrease the load of
H. pylori leading to false-negative results on urease test, UBT,
and SAT.
102
Furthermore the bacterium may inhibit urease activ-
ity.
103
The 14 days are considered a safetyinterval, while a
7-day withdrawal has been shown to be sufcient.
104
H2 receptor antagonists have been shown to have minimal
effect on the sensitivity of UBT, and antacids do not impair the
sensitivity of UBT or SAT. H2-blockers do not have
anti-H. pylori activity.
105107
In contrast, the antibacterial activ-
ity of antibiotics and bismuth compounds necessitate their dis-
continuation for 4 weeks to allow an increase of a detectable
bacterial load.
Statement 3: In clinical practice when there is an indication for endoscopy, and
there is no contraindication for biopsy, the rapid urease test (RUT) is
recommended as a first-line diagnostic test. In the case of a positive test, it
allows immediate treatment. One biopsy should be taken from the corpus and
one from the antrum. RUT is not recommended as a test for H. pylori eradication
assessment after treatment.
Level of evidence: 2b Grade of recommendation: B
The sensitivity of biopsy urease tests is approximately 90%,
and specicity is in the range of 95100%.
108 109
False-positive
tests are unusual; false-negative results can occur in patients
with recent GI bleeding or with the use of PPIs, antibiotics, or
bismuth-containing compounds or with excessive atrophy and
intestinal metaplasia. If RUT is to be performed, patients should
be off antibiotics or bismuth for 4 weeks and off PPI therapy
for 2 weeks.
102 110 111
Obtaining tissue samples from the antrum and the fundus
may increase the sensitivity of the test.
111 112
False-negative tests
are more frequent than false-positive tests and thus a negative
result should not be used to exclude H. pylori. False-positives
are rare and when present may be due to the presence of other
urease containing bacteria such as Proteus mirabilis,Citrobacter
freundii,Klebsiella pneumoniae,Enterobacter cloacae and
Staphylococcus aureus.
113
The main interest for performing the RUT is to obtain a
quick result, which is practical as it allows an eradication treat-
ment to be prescribed immediately.
Statement 4: For assessment of H. pylori gastritis, a minimum standard biopsy
setting is two biopsies from the antrum (greater and lesser curvature 3 cm
proximal to the pyloric region) and two biopsies from the middle of the body.
Additional biopsy from the incisura is considered for detection of precancerous
lesions.
Level of evidence: 2b Grade of recommendation: B
It is known that atrophy and intestinal metaplasia are found
to be more severe close to the lesser than the greater curva-
ture.
114
These lesions, especially in the antrum, can have several
causes besides H. pylori infection, while within the corpus
mucosa most are caused by ongoing or cured H. pylori
infection.
115117
According to the updated Sydney System, biop-
sies are required from the lesser and greater curvature
118
and
from the antrum and corpus.
119
Others showed that two antral
biopsies only
120
(lesser at the incisura region and greater curva-
ture) were sufcient to detect H. pylori. Satoh et al
121
reported
that even one biopsy from the greater curvature sufces and that
in individuals with severe atrophy of the antrum it is more suit-
able at the greater curvature, which is superior to a biopsy from
the lesser curvature and/or incisura. Additionally, in patients
with duodenal ulcer, H. pylori colonisation is denser in the
antrum than in the corpus.
122126
Antral biopsies are recom-
mended to assess the density of colonisation of H. pylori.
It has been shown that the best biopsy sites for detection of
H. pylori and assessment of atrophy are the lesser and greater
curvature of the mid antrum, and the middle gastric body at the
lesser and greater curvature.
121
This is supported by the
updated Sydney System as well
118
and corresponds to the best
biopsy site for the rapid urease test, that is, corpus and incisura
region.
120
In conclusion, a maximum approach for gastric biop-
sies includes the incisura region at the lesser curvature.
In the case of detection of gastric polyps, besides the biopsies
for gastritis assessment, a set of a few targeted biopsies from
such polyps are sufcient for a correct histopathological diagno-
sis. The decision for eventual further intervention can be
planned according to the histopathological result.
109 127 128
For ulcerations and suspicious focal lesions further biopsies
are necessary. The development of new endoscopic techniques
(eg, narrow band imaging (NBI) and blue light imaging (BLI))
with magnifying endoscopy allow targeted biopsies with higher
accuracy and may change the standard recommendation.
129
Statement 5: Most cases of H. pylori infection can be diagnosed from gastric
biopsies using histochemical staining alone. In cases of chronic (active) gastritis
in which H. pylori is not detected by histochemistry, immunohistochemical testing
of H. pylori can be used as an ancillary test. In the case of normal histology no
immunohistochemical staining should be performed.
Level of evidence: 2b Grade of recommendation: A
Histochemical staging is the standard for H. pylori gastritis
assessment. An argument for the use of immunohistochemis-
try (IHC) is that it may shorten the time required for the
search of the bacteria, especially in cases with a low level of
organisms. However, the IHC staining procedure is more
expensive than histochemical stains and it is not available in
all laboratories. Some studies support the use of IHC rou-
tinely, since haematoxylin and eosin (H&E) staining has been
showntobe4299% sensitive and 100% specic when com-
pared to IHC,
130135
while other studies do not, since they
found sensitivity/specicity of IHC to be 97/98% and 90/
100%, when compared to Genta and H&E stains, respect-
ively.
136 137
On the other hand, IHC staining for H. pylori
has a lower inter-observer variation when compared to histo-
chemical stains.
136138
Cases missed by histological stains are typically those with a
low level of H. pylori,
131
while samples without chronic gastritis
(active or inactive) are negative for the organism even when
using IHC.
131133
Use of IHC could thus be restricted to cases
with chronic gastritis (active or inactive), atrophic gastritis
(extensive intestinal metaplasia) or in follow-up biopsies after
eradication treatment for H. pylori, when no organisms are
identied by using histochemical stains. H. pylori density may
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also be low and patchy or the organism may appear as coccoid
forms in patients who receive PPIs.
Statement 6: It is recommended to perform clarithromycin susceptibility testing
when a standard clarithromycin-based treatment is considered as the first-line
therapy, except in populations or regions with well documented low
clarithromycin resistance (<15%). This test can be performed either by a standard
method (antibiogram) after culture or by a molecular test directly on the gastric
biopsy specimen.
Level of evidence: very low Grade of recommendation: weak
Statement 7: After a first failure, if an endoscopy is carried out, culture and
standard antimicrobial susceptibility testing (AST) are recommended to tailor the
treatment, except if a bismuth-based quadruple therapy is considered.
Level of evidence: weak Grade of recommendation: strong
The value of culture is primarily to perform AST for clari-
thromycin, levooxacin, metronidazole, rifamycin, and eventu-
ally amoxicillin and tetracycline. Several studies using tailored
treatments based on H. pylori susceptibility to antibiotics in
comparison with standard empirical triple therapy have shown a
better eradication rate and may be cost-effective.
139 140
The
cost-effectiveness may vary according to the cost of care in a
given country.
The correlation between AST performed by culture and anti-
biogram versus a molecular test, essentially real-time PCR, is
not perfect. Molecular tests are able to detect more cases of het-
eroresistance (a mixed population of susceptible and resistant
organisms) but at this stage we do not have quantitative data on
the proportion of resistant organisms, which can still be eradi-
cated with the different combinations.
In the case of concomitant therapy, if the strain is clarithro-
mycin resistant the other antibiotics will cure the infection.
141
However, in the context of a prudent use of antibiotics, it
appears unjustied to prescribe an antibiotic which will lack ef-
cacy and will induce adverse events and higher cost. Therefore,
if possible it is better to test for clarithromycin resistance.
After a rst failure, if an endoscopy is carried out, culture
(and standard AST) should be considered in all regions before
giving a second-line treatment, because the chance of having a
resistant organism is high, in the range of 6070% for clarithro-
mycin.
142
AST must then use the standard method (antibio-
gram) because it is the only way to test the susceptibility to all
antibiotics and not only to clarithromycin. It is especially
important if a levooxacin-based therapy is planned because
resistance to uoroquinolones is high in some regions and has a
major impact on the success of treatment. In contrast, if a
bismuth-based quadruple therapy is used in these different situa-
tions it is not recommended to perform AST because the risk of
having a tetracycline resistant strain is extremely low and it was
shown that metronidazole resistance has no impact.
143
Statement 8: Serological tests presenting high accuracy, and locally validated, can
be used for non-invasive H. pylori diagnosis.
Level of evidence: 2a Grade of recommendation: B
Serology is a non-invasive diagnostic method for the detec-
tion of H. pylori infection. Under certain clinical circumstances
there are important local changes that may lead to a low bacter-
ial load in the stomach and to a decreased sensitivity of all diag-
nostic methods except serology. These clinical situations include
GI bleeding, atrophic gastritis, gastric MALT lymphoma, and
gastric carcinoma.
A recent comparative study of 29 commercially available
H. pylori serological kits came to the conclusion that some of
the available kits are excellent, with performance parameters
such as sensitivity and specicity above 90%.
100
These results
show considerable improvement over previously published com-
parative analysis.
144146
In general terms ELISA-based methods
are preferred over rapid near-patient tests whose performances
are not currently satisfactory.
Because serology is able to detect past infection with
H. pylori it should not be used as a method to monitor effect-
iveness of eradication. Moreover, because of the low levels of
antibodies, uids such as saliva and urine should not be used to
perform H. pylori serology assays.
Given that regional differences in prevalence of infection,
infection load, and strain distribution are likely to exist, the
development of H. pylori serology kits should ideally be done
using local H. pylori strains, local titres should be established,
and all H. pylori serology kits should be locally validated. New
rapid near-patient tests currently being evaluated may full the
accuracy criteria to be used in the future. Looking specically
for CagA antibodies, which remain positive for a very long
period of time, may allow detection of H. pylori infection in
gastric cancer patients when other tests are negative.
Statement 9: The available data consistently recognise pepsinogen (Pg) serology
as the most useful non-invasive test to explore the gastric mucosa status
(non-atrophic vs atrophic). The PgI/PgII ratio can never be assumed as a
biomarker of gastric neoplasia.
Level of evidence: 2a Grade of recommendation: A
The predictive value of Pg testing is limited in patients har-
bouring antrum-restricted atrophy.
147
Moreover, as observed by
Shiotani et al., the reliability of Pg testing clearly depends on
the cut-off of serum Pg levels as well as the denition used to
identify atrophy.
148
A panel of serological tests (GastroPanel) including serum Pg
(PgI and PgII), gastrin 17 (G-17), and anti-H. pylori antibodies
has recently been proposed as serological biopsyin dyspeptic
patients.
149 150
In populations with a low prevalence of atrophic
gastritis, the negative predictive value of the GastroPanel in
identifying atrophic gastritis is as high as 97% (95% CI 95% to
99%).
151
One of the most recent steps in Pgs validation as markers of
atrophic gastritis was made at the Kyoto Global Consensus
Conference
2
where the experts involved unequivocally agreed
on the following statement: Serological tests ( pepsinogen I and
II and anti-H. pylori antibody) are useful for identifying patients
at increased risk for gastric cancer.
Statement 10: UBT is the best option for confirmation of H. pylori eradication and
monoclonal SAT is an alternative. It should be performed at least 4 weeks after
completion of therapy.
Level of evidence: high Grade of recommendation: strong
UBT is a valid and reliable test in the assessment of H. pylori
eradication in the post-treatment evaluation
152
and SAT can be
used as an alternative.
153
False-negative results can occur in
patients taking PPI and antibiotics. Testing to prove eradication
should be performed at least 48 weeks after completion of
H. pylori therapy. PPI should be discontinued for at least
2 weeks as it interferes with the sensitivity of UBT and
SAT.
95 153155
Antibiotics and PPI contribute to the false-
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negative results obtained with post-eradication UBT by inhibit-
ing growth and by their bactericidal activity against H. pylori.
Statement 11:H. pylori eradication results in significant improvement of gastritis
and gastric atrophy but not of intestinal metaplasia.
Level of evidence: moderate Grade of recommendation: strong
H. pylori infection is a crucial factor in the multistep carcino-
genic process of gastric cancer. In this process the gastric
mucosa evolves through the stages of acute gastritis, chronic gas-
tritis, gastric atrophy, intestinal metaplasia and dysplasia known
as the Correa Cascade before developing gastric adenocarcin-
oma. Over the years one question has prevailed: are there any
long-term benets for the gastric mucosa after H. pylori
eradication?
In recent years (2007, 2011, and 2016) three meta-ana-
lyses
156158
systematically reviewed the long-term effects of
H. pylori eradication on gastric histology (ie, effects on gastric
atrophy and intestinal metaplasia for both antrum and corpus)
by meta-analysing all relevant studies. In all three meta-analyses
the results were consistent, showing signicant improvement of
gastric atrophy, whereas improvement was not shown for intes-
tinal metaplasia.
WORKING GROUP 3: TREATMENT
Statement 1:H. pylori resistance rates to antibiotics are increasing in most parts
of the world.
Level of evidence: moderate Grade of recommendation: strong
Although regionally variable, all areas of the world which
have been studied on more than one occasion show increasing
resistance rates to antibiotics in both high and middle/low
income countries. A recent review on the global emergence of
H. pylori antibiotic resistance conrms that eradication rates
have been declining while the prevalence of antibiotic resistance
rates have been increasing.
159
Such evidence comes from studies
in Europe, Japan, Korea, China, Iran, Greece, Bulgaria and
others.
160165
Moreover, clarithromycin resistance rates have
now reached 30% in Italy and Japan, 40% in Turkey, and
50% in China, although rates in Sweden and Taiwan were
15%.
159
A recent study from Taiwan has studied the impact of
a government introduced restrictive antibiotic policy on
H. pylori resistance rates, indicating the rise in levooxacin
resistance since the restriction of macrolides.
166
Statement 2: PPI-clarithromycin-containing triple therapy without prior
susceptibility testing should be abandoned when the clarithromycin resistance
rate in the region is more than 15%.
Level of evidence: very low Grade of recommendation: weak
There are several explanations for the decrease in efcacy of
standard triple therapy: compliance, high gastric acidity, high
bacterial load, and bacterial strains, but the most important is
the increase in H. pylori resistance to clarithromycin. Following
the European Medicines Agency recommendation on evaluation
of medicinal products indicated for treatment of bacterial infec-
tion, three categories of bacterial species can be dened accord-
ing to their susceptibility to a given antibiotic: usually
susceptible (010% resistant), inconstantly susceptible (1050%
resistant), and usually resistant (>50% resistant). H. pylori now
falls into the second category, except in Northern Europe. In
order to take into account the condence intervals of the preva-
lence and regional differences in a given country, a threshold of
15% was recommended to separate regions of high and low
clarithromycin resistance.
Statement 3: For any regimen, the eradication rate can be predicted if the cure
rates are known for susceptible and resistant strains and the prevalence of
resistance in the population.
For an individual patient a history of any prior use of one of the key antibiotics
proposed will identify likely antibiotic resistance despite low resistance rates in
the population. Susceptibility based results simultaneously provide results that are
both population- and individual-based.
Level of evidence: low Grade of recommendation: strong
Population results are not transferable to other geographical
areas with different patterns of resistance. Success for an indi-
vidual depends on his chance of having a resistant infection,
which is ultimately related to local resistance patterns and previ-
ous antibiotic intake. Most available treatment data are thus
population-specic and lack the data required to be directly
linked to the patterns of resistance and susceptibility in other
populations. These data are thus not generalisable. Clinically
useful information must be susceptibility-based which provides
results that are simultaneously population- and individual-based.
This is relevant for clarithromycin, metronidazole, and levoox-
acin but not for amoxicillin or tetracycline.
Statement 4: In areas of high (>15%) clarithromycin resistance, bismuth
quadruple or non-bismuth quadruple, concomitant (PPI, amoxicillin,
clarithromycin and a nitroimidazole) therapies are recommended.
In areas of high dual clarithromycin and metronidazole resistance, bismuth
quadruple therapy (BQT) is the recommended first-line treatment.
Level of evidence: low Grade of recommendation: strong
In settings with high clarithromycin resistance, the choice of
therapy should be based on the frequency of metronidazole and
dual clarithromycin and metronidazole resistance. In geograph-
ical areas where metronidazole resistance is almost negligible
(eg, Japan), replacing clarithromycin for metronidazole in triple
therapy (ie, PPI-metronidazole-amoxicillin) still shows excellent
cure rates.
167
Dual resistance to clarithromycin and metronidazole >15%
will impair the efcacy of all non-BQTs.
168
The expected rate of
dual resistance according to the individual resistance of both
antibiotics is displayed in online supplementary table S3. If
metronidazole resistance remains stable between 30% and 40%,
clarithromycin resistance would have to be 50% and 40% to
undermine the efcacy of concomitant therapy.
In regions with high clarithromycin resistance (1540%) but
low to intermediate metronidazole resistance (<40%) (a pattern
common for most central and southern European countries and
the USA),
164 169
non-bismuth quadruple concomitant therapy,
prescribed for 14 days,
170
can be an effective alternative as the
prevalence of dual resistant-strains will always be <15%. Recent
studies in Spain,
171174
Greece,
175 176
and Italy
174 177
have con-
sistently shown cure rates ranging from 85% to 94% with con-
comitant therapy.
BQT has proven high efcacy in spite of metronidazole resist-
ance in Europe.
143
In regions of high (>15%) dual clarithromycin and metro-
nidazole resistance, bismuth-containing quadruple therapies are
the treatment of choice. Ideally, clarithromycin should be
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avoided and a combination of alternative antibiotics for which
resistance does not become problematic (eg, amoxicillin, tetra-
cycline, furazolidone, rifabutin) or can be successfully overcome
with increasing doses, dosing interval and duration (eg, metro-
nidazole) should be recommended. In China (with estimated
H. pylori resistance to clarithromycin 2040% and to metro-
nidazole >60%),
178
quadruple therapy with a PPI, bismuth and
a combination of two antibiotics, among furazolidone, tetracyc-
line, metronidazole, and amoxicillin, has been successfully
tested (>90% cure rates) against H. pylori strains resistant to
metronidazole, uoroquinolones, and clarithromycin
179
and
currently is the recommended rst-line treatment.
178
If bismuth is not available in high dual clarithromycin and
metronidazole resistance areas, levooxacin,
180
rifabutin,
181
and
high dose dual (PPI+amoxicillin)
182
treatments can be con-
sidered. If tetracycline is not available in high dual resistance
areas, bismuth-containing quadruple therapy combining fura-
zolidone plus metronidazole or amoxicillin plus metronida-
zole can be considered
178 179
as well as bismuth plus triple
therapy (PPI, amoxicillin, and either clarithromycin or
levooxacin).
183 184
A therapeutic algorithm for geographical areas with high
clarithromycin resistance is provided in gure 1.
Statement 5: The treatment duration of bismuth quadruple therapy should be
extended to 14 days, unless 10 day therapies are proven effective locally.
Level of evidence: very low Grade of recommendation: weak
The doses of bismuth used in H. pylori eradication are
usually administered for 714 days; a meta-analysis involving 35
studies with 4763 patients showed that bismuth salts, on their
own or associated with other antimicrobials used in eradicating
H. pylori infection, are safe and well tolerated.
185
Fischbach
et al
186
performed a meta-analysis evaluating the efcacy,
adverse events, and adherence related to rst-line H. pylori
quadruple eradication therapies. The efcacy of BQT for 1
3 days, 4 days or 7 days was less effective than when given for
1014 days. The combination of PPI, bismuth, metronidazole,
and tetracycline lasting 1014 days achieved 85% eradication
rate, even in areas with a high prevalence of metronidazole
resistance.
A Cochrane systematic review involving 75 studies was per-
formed to study the optimum duration for H. pylori eradication
regimens.
187
Only six studies (n=1157) provided data for PPI
+bismuth+two antibiotics quadruple therapy. The antibiotic
combination included tetracycline and metronidazole, furazoli-
done and amoxicillin, and clarithromycin and amoxicillin.
H. pylori eradication was compared for 14 days versus 7 days,
10 days versus 7 days, and 14 days vs 10 days. None of the com-
parisons suggest that increased duration signicantly improved
treatment effect for bismuth-based quadruple therapy, but
numbers in studies were small. A single large trial provided data
to compare the efcacy and tolerability of a twice-a-day BQT
for 14 and 10 days.
188
The H. pylori eradication rate was not
signicantly different between 14 days (91.6%) and 10 days
(92.6%). Metronidazole resistance data were not available, but
in that area, metronidazole resistance in previous studies was
29%
188
and was 30% in a previous European multicentre
study.
164
Recent studies performed in different regions have achieved
85% eradication with 14 days BQT.
189191
Two RCTs tested a
triple capsule with a combination of bismuth, metronidazole,
tetracycline plus omeprazole for 10 days and reported an
intention-to-treat (ITT) eradication rate 90%.
143 192
A further
study reported a 93% eradication rate as rescue therapy after
failure of standard triple therapy.
193
Currently, BQT should be considered effective provided the
doses are sufcient and the duration is at least 10 days, prefer-
ably 14 days in areas of high metronidazole resistance.
186 194
A
2-week metronidazole use may overcome the negative inuence
of metronidazole resistance.
195
Korean studies also suggest some benet with longer treat-
ment duration.
196199
Statement 6: Clarithromycin resistance undermines the efficacy of triple and
sequential therapy, metronidazole resistance undermines the efficacy of
sequential therapy, and dual clarithromycin and metronidazole resistance
undermines the efficacy of sequential, hybrid and concomitant therapy.
Level of evidence: moderate Grade of recommendation: strong
Figure 1
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Currently, therapeutic expectations with clarithromycin-
containing treatments and BQT can be predicted, depending on
the rate of clarithromycin and metronidazole resistance (see
online supplementary table S4).
168
All non-BQTs are believed to
perform better than triple therapy and be highly effective
against clarithromycin resistance. Sequential therapy achieves
higher cure rates against clarithromycin-resistant strains than 7-
and 10-day triple therapy, but is not superior to 14-day triple
therapy.
200 201
Of note, sequential therapy achieves lower cure
rates compared to concomitant therapy against clarithromycin-
resistant strains, as shown in head-to-head trials (see online sup-
plementary table S5) and in the recent literature (see online sup-
plementary table S6).
Metronidazole resistance is another key factor impairing the
efcacy of sequential therapy. Unlike clarithromycin resistance,
metronidazole resistance can be partially overcome by increasing
the dose, frequency, and duration of the antibiotic. Sequential
therapy provides metronidazole for 57 days, hybrid therapy for
7 days, and concomitant therapy for 1014 days. When compar-
ing the efcacy of sequential and concomitant therapy against
metronidazole-resistant and clarithromycin-susceptible H. pylori
strains, cure rates for sequential therapy have been lower in
head-to-head trials (see online supplementary table S7) and in
the recent literature (see online supplementary table S8). A trial
evaluating the advantage of 14-day sequential over 14-day triple
therapy in Taiwan reported a decision model to predict the
outcome of both therapies. This suggested that sequential
therapy was more effective than 14-day triple therapy only
when metronidazole resistance was <40%.
200
This premise has
been fully corroborated in several further systematic reviews and
meta-analyses,
201204
consistently showing the lack of advantage
of sequential therapy over 14-day triple therapy when sequential
therapy was evaluated in settings with increasing metronidazole
(and dual) resistance.
200
Dual (clarithromycin and metronida-
zole) resistance is the main factor inuencing the efcacy of all
non-BQTs (see online supplementary table S9). It has been pro-
posed that cure rates with sequential, hybrid, and concomitant
therapy will always be <90% when the rate of dual resistant
strains is >5%, >9% or >15%, respectively.
168
Cure rates for
sequential therapy against dual clarithromycin- and
metronidazole-resistant H. pylori strains were considerably
lower than that of concomitant therapy in head-to-head trials
(see online supplementary table S9) and the recent literature
(see online supplementary table S10). As for hybrid therapy, we
currently only have data from two recent trials with a small
number of patients,
174 205
where treatment was effective against
clarithromycin-susceptible and metronidazole-resistant strains
((47/48 (97%)) and, to a lesser extent, against dual resistant
strains ((2/4 (50%)).
201
Statement 7: Currently, concomitant therapy (PPI, amoxicillin, clarithromycin, and
a nitroimidazole administered concurrently) should be the preferred non-bismuth
quadruple therapy, as it has shown to be the most effective to overcome
antibiotic resistance.
Level of evidence: moderate Grade of recommendation: strong
All non-BQTs (concomitant, hybrid, triple, and sequential )
lead to excellent cure rates against susceptible H. pylori strains,
but results may differ when facing populations with different pat-
terns of resistance.
168
Three meta-analyses have shown a similar
efcacy for sequential and concomitant therapy,
201 206 207
as well
as a further one suggesting non-inferiority for hybrid therapy.
208
The results of these meta-analyses should be viewed with caution
due to methodological issues. In the rst meta-analysis, two of
six (33%) included studies compared 5-day concomitant to
10-day sequential therapy, whereas studies comparing both
treatments for 14 days were excluded.
201
In the second
meta-analysis, three of eight (37%) included studies compared
5-day concomitant to 10-day sequential therapy. In the third,
treatment duration was 5, 7, 10, and 14 days for concomitant
therapy and 10 and 14 days for sequential therapy.
207
Of note,
the study with the largest sample size (n=975) which was
included in all of these meta-analyses compared 5-day concomi-
tant to 10-day sequential therapy (in Latin America, with
high clarithromycin and metronidazole resistance).
209
Moreover, meta-analyses have consistently shown that the
efcacy of concomitant therapy is duration-dependent.
210 211
The efcacy of concomitant therapy was signicantly higher
than that of sequential therapy when both treatments were
compared with a similar duration (see online supplementary
gure S2).
Sequential therapy is more complex and requires changing
antibiotic drugs during the treatment course, which can be con-
fusing for patients. Concomitant therapy therefore is more easy
to meet patientsadherence compared to sequential therapy and
tolerability is similar to standard triple therapy.
Data on hybrid therapy are scarce. Possibly due to geograph-
ical differences in resistance patterns, good results have been
published from Spain, Iran, and Taiwan,
171 174 205 212 213
but
unsatisfactory reports from Italy and Korea.
177 214216
Statement 8: The recommended treatment duration of non-bismuth quadruple
therapy (concomitant) is 14 days, unless 10 day therapies are proven effective
locally.
Level of evidence: very low Grade of recommendation: weak
Early studies from Europe and Japan suggested that a short
course of 35 days with three antibiotics and a PPI could
achieve reasonable eradication rates.
217
In a rst meta-analysis
including nine studies, very short treatment durations of some
of the trials with concomitant therapy yielded excellent
results but the duration of therapy became a signicant
variable.
Gisbert and McNicholl, in a meta-analysis involving 55
studies (n=6906), were unable to nd clear evidence for higher
eradication results with longer treatments. However, several
RCTs compared, in the same study and with the same protocol,
two different durations of concomitant therapy, and demon-
strated that the longer duration is more effective.
215 218220
Moreover, suboptimal results have been observed with a 5-day
treatment duration in Latin America
209
(73.5%) and South
Korea (58.6%),
221
but also in two studies of 14-day treatment
from Turkey (75%)
222
and South Korea (80.8%).
223
These
inferior results have been attributed to the high prevalence of
H. pylori strains resistant to clarithromycin and especially
metronidazole in these populations.
168 170
A recent study has
compared the efcacy and tolerability of the standard and the
so called optimisedconcomitant regimen (new generation PPIs
at high doses of esomeprazole 40 mg twice daily and longer
treatment duration 14 days), demonstrating higher eradication
rates with the optimised regimen (91% vs 86%).
224
Although
the incidence of adverse events was higher with the optimised
treatment, these were mostly mild and did not negatively impact
the compliance.
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In another multicentre study, the OPTRICON trial,
172
the
authors compared the effectiveness and safety of two opti-
misedtriple and concomitant therapies (with esomeprazole
40 mg twice daily) for 14 days. The optimised concomitant
therapy achieved signicantly higher eradication rates. Adverse
events were signicantly more common with optimised con-
comitant therapy, but full compliance with therapy was similar
between groups.
Statement 9: In areas of low clarithromycin resistance, triple therapy is
recommended as first-line empirical treatment. Bismuth-containing quadruple
therapy is an alternative.
Level of evidence: high Grade of recommendation: strong
In these regions the standard PPI-clarithromycin-containing
regimen is still recommended as the rst-line treatment.
Bismuth-based quadruple regimens are valid rst-line
alternatives.
Statement 10: The use of high dose PPI twice daily increases the efficacy of triple
therapy. Esomeprazole and rabeprazole may be preferred in Europe and North
America where the prevalence of PPI extensive metabolisers is high.
Level of evidence: low Grade of recommendation: weak
H. pylori is more likely in a non-replicative state when gastric
pH is low (pH 36); by raising pH, bacteria enter the replicative
state and become susceptible to amoxicillin and clarithromy-
cin.
225
The role of PPIs is supported by the results of several
meta-analyses, where signicantly higher eradication rates were
found with clarithromycin and amoxicillin or metronidazole-
containing triple-therapy regimens and twice-daily PPI com-
pared with once-daily PPI.
226228
Response to PPI is strongly determined by the capacity of the
patient to metabolise the drug, which is determined by the cyto-
chrome 2C19 and MDR polymorphisms. These polymorphisms
can affect the success rate of eradication therapy; higher PPI
doses, controlling gastric pH adequately, can be crucial for
eradication in extensive metabolisers. Caucasian subjects show a
higher prevalence of high metabolisers (5681%) compared to
Asian, and in particular Japanese people.
170 229233
Some
meta-analyses show that the success rates of omeprazole- and
lansoprazole-containing triple therapies are affected by
CYP2C19 polymorphisms whereas there is no impact on regi-
mens that include rabeprazole and esomeprazole. Rabeprazole
has been suggested as the PPI least affected by CYP2C19 geno-
type, being mainly metabolised through a non-enzymatic
process. Esomeprazole and rabeprazole provide better overall
H. pylori eradication rates, especially esomeprazole 40 mg twice
daily, whereas rabeprazole 10 and 20 mg twice daily maintained
results compared to rst-generation PPIs.
234239
Statement 11: The treatment duration of PPI-clarithromycin based triple therapy
should be extended to 14 days, unless shorter therapies are proven effective
locally.
Level of evidence: moderate Grade of recommendation: strong
Several meta-analyses with similar results have been published
to date.
187 240242
All consistently show that 14-day triple ther-
apies increase cure rates when compared to 7 days. Ten-day
therapies were also superior to 7-day therapies. The increases in
cure rates were superior with 14 day than with 10 day therapy
in all meta-analyses and no differences in side-effect rates were
observed in any of the reviews. Ultimately it has to depend on
the physician prescribing in each particular area, taking into
account the local efcacy, tolerability adverse events and costs.
Cardiovascular outcomes need to be considered in the context
of prolonged clarithromycin use.
243
In general, shorter duration
should be reserved only for regions where equally high treat-
ment success is demonstrated.
244
Statement 12: After failure of bismuth-containing quadruple therapy, a
fluoroquinolone-containing triple or quadruple therapy may be recommended. In
cases of high quinolone resistance, the combination of bismuth with other
antibiotics, or rifabutin, may be an option.
Level of evidence: very low Grade of recommendation: weak
In theory, any treatment could be used after failure of BQT,
including repeating the same BQT with longer duration and
high metronidazole dosage. However, it seems wiser never to
repeat a treatment that has already failed. Studies evaluating the
efcacy of a third-line combination of a PPI, amoxicillin, and
levooxacin for the eradication of H. pylori infection after two
eradication failures, with the second-line treatment including a
bismuth quadruple regimen, are summarised in online supple-
mentary table S11.
245248
Moxioxacin triple therapy has been
recently reported to achieve a 67% eradication rate as second-
line treatment after rst-line bismuth quadruple failure in 28
patients in Korea.
249
In a study from China, bismuth therapy
was effective as rst-line treatment in 99% of patients, and in
the two patients who failed, sequential therapy was effective.
250
Using a clarithromycin-containing treatment as second-line
therapy after failure of a BQT does not seem to be practical
since bismuth therapies are usually proposed as rst-line treat-
ments for areas of high clarithromycin resistance.
Levooxacin-based triple therapy, that is known to be effective
as second-line therapy after clarithromycin-containing
therapy,
251 252
should also be recommended after failure of a
bismuth-containing quadruple regimen.
Statement 13: After failure of PPI-clarithromycin-amoxicillin triple therapy, a
bismuth-containing quadruple therapy or a fluoroquinolone-containing triple or
quadruple therapy are recommended as a second-line treatment.
Level of evidence: low Grade of recommendation: weak
After failure of PPI-clarithromycin-amoxicillin triple therapy,
either primary or acquired clarithromycin resistance should be
expected, therefore repeating the same regimen must be
avoided. Indeed, a pooled analysis of eight studies showed a
very low eradication rate of 46% when repeating a
clarithromycin-based therapy.
253
Based on previous
meta-analyses demonstrating a similar effectiveness with the two
regimens,
251 252 254
Maastricht IV guidelines recommended
either a bismuth-containing quadruple therapy or a levooxacin-
containing triple therapy. A recent meta-analysis of RCTs sup-
ports the use of either a levooxacin-containing triple therapy
(see online supplementary gure S3) or a bismuth-containing
quadruple therapy (see online supplementary gure S4) as an
effective second-line therapy for H. pylori eradication.
253
Moreover, a similar efcacy of PPI-levooxacin-amoxicillin
triple therapy and bismuth-containing quadruple therapy after a
rst-line treatment failure with a PPI-amoxicillin-clarithromycin
was shown, providing cure rates of 76% and 78%, respectively.
However, the incidence of side effects was lower with
levooxacin-containing triple therapy than with bismuth-
containing quadruple therapy.
255
A sub-group analysis showed
similar eradication rates with 500 mg (either once a day or
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250 mg twice a day) and 1000 mg (500 mg twice a day) of levo-
oxacin, thus suggesting that the low-dose regimen should be
preferred.
255
Conversely, an increased prevalence of primary
levooxacin resistance has been recently reported and this may
affect the efcacy of levooxacin-based regimens.
256
Therefore,
bismuth-containing quadruple therapy continues to represent a
valid second-line treatment for H. pylori eradication, particu-
larly in areas with high uoro quinolones resistance. In second
line, a 14-day bismuth quadruple treatment provides higher
eradication rates than 7-day treatment.
257
A potential role for
quadruple therapy with the novel 3 drugs in one pillis foresee-
able in this setting.
143
Recent data have conrmed that combining bismuth and levo-
oxacin in a 14-day quadruple therapy is an effective (90%
cure rate), simple, and safe second-line strategy in patients
whose previous standard triple has failed.
258
Several studies pre-
viously evaluated this quadruple regimen (PPI, amoxicillin, levo-
oxacin, and bismuth) as reported in online supplementary
table S12.
The use of a triple therapy with a PPI, amoxicillin, and
metronidazole has provided encouraging results with an overall
eradication rate of 87%; moreover, the inclusion of studies
where PPI-amoxicillin-metronidazole treatments were adminis-
tered three times daily may explain the superiority, even in
shorter regimens.
253
However, there are no clinical trials com-
paring this treatment with BQT and only two small comparative
studies with PPI-levooxacin-amoxicillin-triple therapy are
available.
259 260
Statement 14: After failure of a non-bismuth quadruple therapy, either a bismuth
quadruple therapy or a fluoroquinolone-containing triple or quadruple therapy are
recommended.
Level of evidence: very low Grade of recommendation: weak
A systematic review and meta-analysis has been performed to
explore effective second-line treatments after an unsuccessful
attempt to eradicate H. pylori infection with non-BQTs
(updated meta-analysis for the consensus). Sixteen studies were
selected: seven treating patients after concomitant failure, 15
after sequential failure, and one after hybrid failure. Most
studies evaluated a rescue therapy with levooxacin, amoxicillin,
and a PPI, which obtained an overall 78% eradication rate (201
patients) after the failure of a non-BQT (see online supplemen-
tary gure S5).
176 177 261264
This triple therapy
(levooxacin-amoxicillin-PPI) was similarly effective after failure
of both sequential (81%) (see online supplementary gure S6)
and concomitant (78%) (see online supplementary gure S7)
treatment. Only one study reported results of the levooxacin
triple therapy after failure of hybrid therapy, with a 50% cure
rate. Tolerance of this regimen was acceptable. Four patients
stopped the treatment due to side effects.
Some authors have included moxioxacin instead of levoox-
acin in this triple rescue regimen (moxioxacin-amoxicillin-PPI),
achieving an overall eradication rate of 71%
249 265 266
after
failure of non-BQTs. These results should be interpreted with
caution, due the heterogeneity of the data and the differences
between study characteristics.
An important caveat of the levooxacin-containing therapy is
that it is markedly less effective in the presence of uoroquino-
lone resistance.
267
The efcacy of levooxacin-containing
therapy is decreasing, most likely due to increased primary quin-
olone resistance.
268
Bismuth has a synergistic effect with anti-
biotics, and overcomes clarithromycin and levooxacin
resistance.
269 270
A quadruple regimen adding bismuth (PPI,
amoxicillin, levooxacin, bismuth) showed encouraging
results.
270273
In patients randomly assigned to receive PPI,
amoxicillin, and levooxacin with or without bismuth for
14 days, the eradication rate was slightly higher with the
bismuth-based regimen (87% vs 83%); but in levooxacin-
resistant strains, the bismuth combination was still relatively
effective (71%) while the non-bismuth regimen achieved
H. pylori eradication in only 37% of the patients.
270
With a
second-line quadruple regimen containing bismuth, levooxa-
cin, amoxicillin, and esomeprazole for 14 days in patients who
failed H. pylori eradication treatment, cure rates were similar.
258
Therefore, the levooxacin/bismuth-containing quadruple
therapy constitutes an encouraging second-line strategy not only
in patients failing previous standard triple therapy but also non-
bismuth quadruple sequentialor concomitanttreatments.
BQT (PPI-bismuth-tetracycline-metronidazole) after failure of a
non-BQT (after failure of a sequential regimen in both cases) is
effective (see online supplementary gure S8). Little experience
is available with other treatment options.
200 274 275
Statement 15: After failure of second-line treatment, culture with susceptibility
testing or molecular determination of genotype resistance is recommended in
order to guide treatment.
Level of evidence: very low Grade of recommendation: weak
After failure of a second-line strategy, treatment should be
guided by AST, whenever possible. Resistance to clarithromy-
cin, levooxacin or rifabutine has a major negative impact on
the results of triple therapies. Resistance to metronidazole has
a less marked negative effect. Susceptibility-guided triple ther-
apies proved more effective than empirical triple therapies in
rst-line treatment.
139 276
In a systematic review, benets of
tailored treatment in second-line treatment remain uncertain,
and there is no comparative data for third-line treatment. In
most of these studies, strains were only tested for clarithromy-
cin susceptibility.
There are no data comparing empirical with susceptibility-
guided sequential therapy. However, an optimal efcacy of a
genotype resistance-guided sequential therapy in third-line treat-
ment of refractory H. pylori infection has been reported.
277
Non-bismuth-containing quadruple treatment had a signi-
cant impact on dual resistance.
176
Better results with
susceptibility-guided triple therapy than with empirical con-
comitant therapy were obtained in a region of high clarithromy-
cin resistance.
278
Bismuth-containing quadruple therapy is the
least dependent treatment on antibiotic resistance. Tetracycline
resistance is very rare and not expected to develop despite treat-
ment failures. Metronidazole resistance does not decrease eradi-
cation rates.
143 192 279
Statement 16: After failure of the first-line treatment (clarithromycin based) and
second-line treatment (with bismuth-containing quadruple regimen), it is
recommended to use the fluoroquinolone-containing regimen. In regions with a
known high fluoroquinolones resistance, a combination of bismuth with different
antibiotics or a rifabutin-containing rescue therapy should be considered.
Level of evidence: very low Grade of recommendation: weak
This scenario reects the therapeutic approach as recom-
mended rst- and second-line regimens proposed by the
Maastricht IV Consensus conference. A study tested this
approach in clinical practice and used as third-line empirical
therapy a levooxacin-based regimen. This achieved high cumu-
lative H. pylori eradication rates.
247
Several studies have
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conrmed the efcacy of a third-line combination of a PPI,
amoxicillin, and levooxacin for the eradication of H. pylori
infection after two eradication failures.
245 247 251 252
However,
given the rise in levooxacin resistance, the prevalence of resist-
ance must be taken into account.
280
In known high local uoro
quinolones resistance, rifabutin-containing rescue therapy likely
represents the better therapeutic option.
281
Studies evaluating
the efcacy of a third-line combination of a PPI, amoxicillin,
and levooxacin for eradication of H. pylori infection after two
eradication failures (rst-line with a
PPI-clarithromycin-amoxicillin, and second-line with a bismuth
quadruple regimen), are summarised in online supplementary
table S13.
Statement 17: After failure of the first-line treatment (triple or non-bismuth
quadruple) and second-line treatment (fluoroquinolone-containing therapy), it is
recommended to use the bismuth-based quadruple therapy.
Level of evidence: very low Grade of recommendation: weak
A quadruple regimen of bismuth, metronidazole, and tetra-
cycline plus omeprazole produces a high eradication rate in
patients previously failing H. pylori eradication regimens. This
bismuth-based regimen offers an effective option as rescue
therapy.
143 193 282 283
Furthermore, BQT is not inuenced by
clarithromycin and uoroquinolone resistance.
284
Statement 18: After failure of first-line treatment with bismuth quadruple and
second-line treatment (fluoroquinolone-containing therapy), it is recommended to
use a clarithromycin-based triple or quadruple therapy. A combination of bismuth
with different antibiotics may be another option.
Level of evidence: very low Grade of recommendation: weak
In this scenario, no clarithromycin has been used previously.
Therefore, clarithromycin-based triple therapy (in areas of low
clarithromycin resistance) or non-BQTs (in areas of high clari-
thromycin resistance) are effective options. Another therapeutic
option is the repeat-use of bismuth plus a combination of two
antibiotics not previously used.
191
Statement 19: In patients with penicillin allergy, in areas of low clarithromycin
resistance, for a first-line treatment, a PPI-clarithromycin-metronidazole
combination may be prescribed, and in areas of high clarithromycin resistance,
BQT should be preferred.
Level of evidence: very low Grade of recommendation: weak
Only a minority of patients presenting with a history of peni-
cillin allergy have evidence of immune-mediated hypersensitiv-
ity. Negative allergy testing enables the use of penicillin as
rst-line treatment when necessary so that these patients are not
excluded from the best therapy.
285288
The substitution of
amoxicillin by metronidazole is not an effective option because
of dual resistance.
289 290
A 10-day treatment with PPI-tetracycline and metronidazole
was effective in patients with documented penicillin allergy.
291 292
This triple combination was better with the addition of bismuth
(resulting in a quadruple regimen), and may be a better alterna-
tive for rst-line treatment in the presence of penicillin
allergy (especially in areas with high metronidazole and/or
clarithromycin resistance).
293
A 10 to 14 days eradication
regimen in penicillin-allergic patients and failure of previous
PPI, clarithromycin, metronidazole with classical BQT
(PPI-bismuth-tetracycline-metronidazole) or a modied bismuth
quadruple regimen with PPI-bismuth-tetracycline-furazolidone is
very effective.
193 294
Statement 20: Rescue regimen: A fluoroquinolone-containing regimen may
represent an empirical second-line rescue option in the presence of penicillin
allergy.
Level of evidence: very low Grade of recommendation: weak
Fluoroquinolone-containing regimens in various combinations
are effective;
242 293
however, resistance to quinolones is
acquired easily, and in countries with high consumption of these
drugs the resistance rate is relatively high.
294
A sitaoxacin-based regimen is an option, successfully tested
in Japan.
295 296
WORKING GROUP 4: PREVENTION/PUBLIC HEALTH
Statement 1:H. pylori infection is accepted as the major aetiological factor for
gastric cancer.
Level of evidence: 1a Grade of recommendation: A
This is now established beyond doubt from numerous strands
of evidence, including epidemiology, molecular studies, animal
studies, and eradication studies in humans, showing a reduced
incidence of gastric cancer in those receiving eradication
therapy. While Epstein-Barr virus and other rare causes (includ-
ing hereditary ones) might account for a small proportion of
gastric cancers worldwide, it is acknowledged that at least 90%
of cancers are related to H. pylori infection. The risk of cancer
arising from H. pylori infection is identical for gastric cancer of
both intestinal and diffuse type.
297302
Statement 2:H. pylori infection is also a risk factor for proximal gastric cancer
(PGC) provided that oesophageal and junctional adenocarcinoma have been
properly excluded.
Level of evidence: 2c Grade of recommendation: B
The initial epidemiological studies that assessed the risk of
H. pylori in the development of gastric cancer exclusively
focused on distal gastric cancer (non-cardia gastric cancer,
NCGC).
303 304
In nearly all epidemiological reports the traditional distinction
between PGC and NCGC is not addressed; they also fail to dis-
tinguish adenocarcinoma originating from or proximal to the
gastroesophageal junction from that originating in the cardia
mucosa and thus do not address the distinction between
Barretts cancer, true junctional gastric cancer, and PGC. The
distinction has been made in only a few studies. In these where
the correct origin of PGC has been made the prevalence of
H. pylori is the same as for NCGC.
305307
Accordingly,
H. pylori is the principal risk factor for gastric adenocarcinoma
in all sites.
Statement 3:H. pylori eradication reduces the risk of gastric cancer development.
Level of evidence: low Grade of recommendation: moderate
Although cohort investigations consistently suggest that
H. pylori infection is a powerful risk factor for gastric cancer,
the evidence that the risk is reduced by H. pylori eradication is
based so far on two randomised interventional trials.
301 308
Pooled data from the most recent published meta-analysis shows
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the incidence rate ratio=0.53 (CI 0.44 to 0.64). Eradication
provided signicant benet for asymptomatic infected indivi-
duals and individuals after endoscopic resection of early gastric
cancer.
309
The overall gastric cancer risk reduction can be esti-
mated at 34%. Several trials are ongoing in China, UK, and
Korea currently, including a large one with 184 786 partici-
pants; these should provide more reliable data relating to any
benet or adverse consequences that accrue from H. pylori
eradication in the prevention of gastric cancer.
310 311
Statement 4: The influence of environmental factors is subordinate to the effect
of H. pylori infection.
Level of evidence: 2a Grade of recommendation: A
Although the International Agency for Research on Cancer
(IARC) monographs classify H. pylori as a group 1 carcinogen
that causes NCGC,
312
several authors have postulated that
H. pylori is a necessary but not sufcient cause.
313
Casecontrol
studies that have corrected for the observation that the bacter-
ium and its markers may be lost from the stomach when severe
atrophy is present, have established either past or present
H. pylori in almost all non-cardia cancers. Cohort studies have
similarly documented that there was exposure to H. pylori in
the vast majority of cases. A Japanese cohort study showed that
all of the cancers had developed in H. pylori-positive subjects
with none in the negatives.
314
A recent re-analysis of the
Eurgast-EPIC cohort has been undertaken. The study comprised
a follow-up of 500 000 subjects from 10 European countries
aged 4065 years. The Western blot assay was used to test for
H. pylori exposure before diagnosis. It found that 93.2% of the
cancer cases were positive compared with 58.9% of the con-
trols.
315
Factors such as excessive salt intake and cigarette
smoking, different from epidemiological studies that did not
take into account the role of H. pylori, had only a low add-on
effectin the presence of H. pylori infection. The attributable
risk fraction of H. pylori to gastric cancer, based on a pooled
analysis of three cohort studies in Europe and Australia, was
recently estimated at 89%.
316
It is unclear whether the small fraction of cases where
H. pylori is not detectable is associated with other aetiologic
factors (eg, Epstein-Barr virus) or is related to misclassication.
Moreover, it is unknown whether cofactors are necessary in all
cases or whether infection alone leads to gastric cancer.
Statement 5:H. pylori eradication abolishes the inflammatory response and early
treatment prevents progression to preneoplastic lesions.
Level of evidence: 1b Grade of recommendation: B
A rapid decrease of active inammation in gastric mucosa
occurs following H. pylori eradication. This can be demon-
strated by morphological improvement of mucosa both in the
antrum and corpus of the stomach
317
or biomarker results, in
particular a rapid decrease in PgII (indicator for active inamma-
tion) levels following successful H. pylori eradication. A
decrease in PgII has been demonstrated within 12 months fol-
lowing H. pylori eradication.
318 319
Improvement of the
mucosal status has also been demonstrated with high-resolution
endoscopy 3 months after eradication.
320
Epidemiological evidence shows that H. pylori eradication
prevents progression towards precancerous lesions; in Matsu
Island (Taiwan) there was a 77.2% reduction in atrophy (but not
intestinal metaplasia).
321
The observation that H. pylori eradica-
tion prevents the progression of preneoplastic lesions is also
supported by a recent meta-analysis on prevention of metachro-
nous gastric lesions by eradication after endoscopic resection of
gastric neoplasms.
322
Statement 6:H. pylori eradication reverses gastric atrophy if intestinal metaplasia
is not present and arrests the progression of preneoplastic to neoplastic lesions in
a subset of patients.
Level of evidence: 1b Grade of recommendation: A
H. pylori eradication heals chronic active gastritis. This may
be associated with a certain restitution of glands with specialised
cells, and thus a reduction of atrophic gastritis.
42 323 324
Several meta-analyses have shown that gastric atrophy can be
reversed to a degree in both the antrum and corpus.
157 325327
This is not the case once intestinal metaplasia becomes estab-
lished. Intestinal metaplasia cannot be reversed although its pro-
gression is halted in a large subset of patients.
Statement 7: The risk of developing gastric cancer can be reduced more
effectively by employing eradication treatment before the development of atrophy
and intestinal metaplasia.
Level of evidence: 2b Grade of recommendation: B
There remains a considerable gap in knowledge as to how
early, in terms of the degree and extent of the preneoplastic
lesion, eradication of H. pylori may still be successful in prevent-
ing progression to gastric cancer.
A systematic review of the literature, of randomised trials, and
of population H. pylori screening and treatment has shown that
eradication therapy reduces the risk of developing gastric
cancer.
327
In this review, two randomised trials
301 308
evaluated
gastric cancer incidence in participants with and without pre-
neoplastic lesions at baseline. The relative risk of gastric cancer
in 2060 participants with preneoplastic lesions at baseline in
those receiving H. pylori eradication therapy was 0.78 (95% CI
0.46 to 1.34). This compared with a relative risk of 0.24 (95%
CI 0.04 to 1.52) in the 1812 participants without preneoplastic
lesions. There was a non-signicant trend to suggest that the
efcacy of H. pylori eradication was greater in those without
preneoplastic lesions. This potential difference was driven by
one study
308
with no trend seen in the other trial.
301
Statement 8:H. pylori eradication for gastric cancer prevention is cost-effective in
communities with a high risk for gastric cancer.
Level of evidence: moderate Grade of recommendation: strong
Nine economy-based modelling studies have evaluated the
cost-effectiveness of population H. pylori screen-and-treat pol-
icies for the prevention of gastric cancer. They employed differ-
ent assumptions and methods, but concluded that H. pylori
screening and treatment was cost-effective. The key assumption
is that H. pylori eradication reduces gastric cancer risk and this
is now supported by a systematic review.
327
The benet is likely
to be highest in communities with a high risk of gastric cancer
(where all these randomised trials were conducted.) However, it
may also be cost-effective in developed countries because rando-
mised trials have shown that population H. pylori screening and
treatment reduces dyspepsia costs.
327 328
This could result in
the programme being cost neutral.
Statement 9:H. pylori eradication offers clinical and economic benefits other
than gastric cancer prevention and should be considered in all communities.
Level of evidence: low Grade of recommendation: weak
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While there is ample evidence for cost-effectiveness in high
prevalence countries and specic high risk groups in gastric
cancer prevention, a benet is also reported for low prevalence
countries.
329
The clinical and economic benets of H. pylori eradication
extend to its role in peptic ulcer prevention, a disease that is
responsible for a serious burden of morbidity and mortality
throughout the world.
18 47 330
H. pylori eradication also
reduces peptic ulcer bleeding relapses, the development of
NSAID induced ulcers, and unexplained dyspeptic symptoms.
Additional benecial health outcomes have also been consid-
ered. From an economic perspective the test-and-treat policy
may be cost-effective within 10 years.
Statement 10:H. pylori screen-and-treatstrategies are recommended in
communities at high risk of gastric cancer.
Level of evidence: moderate Grade of recommendation: strong
So far such strategies have been conducted in few countries
(Taiwan, China).
301 321
Screen-and-treat strategies are recom-
mended in high-risk populations and are considered to be cost-
effective as to the expected level of adverse events and compli-
ance;
331
a large population-based Chinese screen-and-treat trial
undertaken in a rural area at high risk of gastric cancer reported
excellent compliance, minor adverse effects and low cost,
altogether indicating good feasibility. Long-term follow-up in
gastric cancer prevention trials will provide a nal answer.
310
Statement 11: A screen-and-treat strategy of H. pylori gastritis should be
considered in communities with intermediate to low risk for gastric cancer
Level of evidence: low Grade of recommendation: weak
Maastricht IV guidelines indicated that screen-and-treat
should be explored in communities with a signicant burden of
gastric cancer
1
because several randomised clinical trials had
shown a 3040% reduction in gastric cancer risk in those in
whom H. pylori had been successfully eradicated.
327
However,
the burden of disease is important in lower risk areas as well.
There were an estimated 12 000 deaths from gastric cancer in
the USA in 2012 and 58 000 in the 28 countries of the
European Union. Gastric cancer mortality remains high because
in most cases the condition is incurable at the time the diagnosis
is made, so prevention is the most appropriate way forward.
332
Another concern in these countries at intermediate or relatively
low risk is that there may be areas, populations or ethnic groups
where the incidence is high (eg, migrants from high incidence
areas).
H. pylori screen-and-treat is cost-effective in published
reports, even though the majority of models have been elabo-
rated for developed countries (eg, USA, UK.) The economic
benetofH. pylori eradication is greater if reductions in dys-
pepsia and peptic ulcer disease are considered. However, the
potential deleterious effects of H. pylori eradication, including
antibiotic resistance/adverse events, need to be taken into
consideration.
The IARC working group meeting of December 2013 con-
cluded that countries should explore the possibility of introdu-
cing population-based H. pylori screen-and-treat programmes,
taking account of disease burden and other health priorities such
as cost-benet analysis and possible adverse consequences.
332
They should also include a scientically valid assessment of
programme process and feasibility.
Statement 12: Screen-and-treat for H. pylori is recommended in individuals at
increased risk for gastric cancer.
Level of evidence: moderate Grade of recommendation: strong
Individuals with the gastric cancer phenotypeare at increased
risk of cancer. This is characterised by corpus predominant gastri-
tis, gastric atrophy/intestinal metaplasia, hypochlorhydria, and
evidence of current or past H. pylori infection. Screening on a
population-wide basis by invasive approaches is not feasible but
the gastric cancer phenotype can be detected by a combination of
non-invasive markers including H. pylori serology and pepsin-
ogen levels (Pgl or Pgl/II ratio).
333 334
Genomic approaches are
also promising but require validation in prospective studies.
335
Some indigenous sub-populations and immigrants from high inci-
dence countries may also be at increased risk and could be tar-
geted for screening and prevention.
336 337
Those with a positive
family history have a modestly increased risk and in the presence
of H. pylori infection have an increased prevalence of preneoplas-
tic abnormalities including atrophy and hypochlorhydria.
338 339
They should also be screened and treated.
Statement 13: Endoscopy-based screening should be considered as an option in
communities and individuals at increased risk of gastric cancer.
Level of evidence: very low Grade of recommendation: weak
Certain countries and communities have a considerably
increased risk of gastric cancer compared with others and in
these screening endoscopy is a valid option.
18 340 341
Individuals within those communities who are at a much
higher risk of developing gastric cancer may be identied by
serological screening and offered endoscopic screening and
surveillance.
342 343
Statement 14: Advanced preneoplastic lesions (atrophy/intestinal metaplasia)
require follow-up by endoscopic staging.
Level of evidence: very low Grade of recommendation: moderate
This recommendation was rst released within a guideline
based on the evidence that the risk of progression is maximised
in the presence of preneoplastic lesions.
149 344348
The selection
of patients for follow-up should be based on histological classi-
cation criteria (OLGA/OLGIM: operative link for gastritis
assessment/operative link for gastric intestinal metaplasia
assessment).
344 346
Statement 15: Public awareness campaigns for prevention of gastric cancer
should be encouraged.
Level of evidence: D Grade of recommendation: A
Public awareness campaigns in a number of countries have
focused on the prevention of colorectal cancer and have led to
the introduction of national screening programmes based on
colonoscopy and/or stool blood positivity. They target indivi-
duals in the at-risk age range (5065 or 70 years.) It is largely
accepted that acceptance rates for screening are related to the
extent of public awareness on the topic. The methodology used
in public awareness campaigns differ in their communication
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strategies: paid media, public service announcements, public
relations, media advocacy, government relations, and community
activities. Communication strategies can be assessed on three
levels of evaluation: (1) short-term outcomes (awareness, atti-
tude shifts); (2) intermediate outcomes (knowledge, attitude/
policy shifts); (3) long-term outcomes (changes in behaviour,
disease rate changes).
Public awareness of gastric cancer risk factors and disease
screening in high risk regions should be encouraged but public
awareness campaigns on gastric cancer may lead to
over-investigation.
Statement 16: Mass eradication using a screen-and-treatstrategy with
commonly used antibiotics may create additional resistance selection pressure on
pathogens other than H. pylori.
Level of evidence: 1b Grade of recommendation: A
The widespread use of antibiotics for gastric cancer preven-
tion that are commonly used for treating life-threatening dis-
eases (eg, amoxicillin, clarithromycin, levooxacin) may select
resistance in bacteria other than H. pylori.
349 350
Use of a single macrolide in the dose and duration of the short-
est H. pylori eradication regimen (clarithromycin 500 mg twice
daily for 7 days) increased the resistance of macrolide-resistant
pharyngeal Streptococcus pneumoniae in a placebo-controlled
study in healthy volunteers. The difference was statistically signi-
cant over the entire study period of 180 days.
289
Use of macrolides has been associated with an increase in
resistance of Streptococcus pyogenes and Staphylococcus aureus
that are frequent causes of community-acquired infections.
Extensive use of uoroquinolones is associated with a marked
increase in resistance of uropathogenic Escherichia coli and circu-
lation of ESBL (extended-spectrum beta-lactamases)-producing
multi-drug resistant bacterial strains. The same applies to the use
of amoxicillin that already has very high resistance rates in most
countries. The spread of highly pathogenic Clostridium difcile
ribotype 027 that is resistant to uoroquinolones can be facili-
tated by use of these drugs.
Alternative treatment regimens could be considered in public
health campaigns to minimise this undesirable ecological side
effect. Bismuth, tetracycline, and metronidazole are less import-
ant antibacterial agents in managing life-threatening disease, and
therefore are more appropriate in public health settings.
Resistance to rifabutin can develop after several months of pro-
longed use of the drug, therefore short-duration treatment is
not expected to increase the resistance of Mycobacterium tuber-
culosis substantially.
Statement 17: An effective vaccine against H. pylori would be the best public
health measure against the infection.
Level of evidence: 4 Grade of recommendation: D
A successful H. pylori vaccine eld trial from China
351
has
recently been reported. This is a promise for the future and
demands increased efforts for further development of a vaccine.
WORKING GROUP 5: H. PYLORI AND THE GASTRIC
MICROBIOTA
Statement 1: Gastric microbiota includes other microbes beyond H. pylori.
Level of evidence: 2c Grade of recommendation: B
The stomach, as with other parts of the GI tract, harbours its
own microbiota, of which H. pylori is its best known compo-
nent, but certainly not the only one. Up to now, only a few
studies have investigated the composition of gastric microbiota
through culture-independent, molecular approaches (eg, 16S
rDNA sequencing analysis), focusing mainly on the analysis of
bacteria. In healthy conditions, the main phyla of gastric micro-
biota are Proteobacteria, Firmicutes, Bacteroidetes, and
Actinobacteria, whereas the most commonly found genus in the
stomach is Streptococcus.
352356
The composition of the gastric
microbiota appears to be substantially different from that of the
oral and throat microbiota.
357
This indicates that the gastric
microbiota is composed of resident microbes rather than those
derived from the passage of microorganisms from upper organs.
Statement 2: The composition of a healthy gastric microbiota and how H. pylori
affects this microbiota have not yet been fully defined.
Level of evidence: 5 Grade of recommendation: D
In spite of an increasing body of evidence,
352357
the exact
composition of a healthy gastric microbiota remains uncharac-
terised and the relationship between H. pylori and other gastric
microorganisms is yet to be fully dened.
355 358
Nevertheless,
some evidence shows that H. pylori decreases the diversity of
the gastric microbiota,
352
suggesting a predominance of
H. pylori over other microbes.
Statement 3: Components of the gastric microbiota may play a role in the
development of H. pylori-related diseases.
Level of evidence: low Grade of recommendation: weak
Alterations of the human gastric microbiota have been found
in different gastric diseases, including those arising as a compli-
cation of H. pylori-related gastritis. The reduced acid secretion
of the atrophic stomach supports the growth of a number of
microorganisms whose development is retarded by the low
gastric pH in healthy conditions. To date, there are few data on
the microbial pattern of atrophic gastritis. Overall, lower micro-
bial richness is signicantly associated with a lower serum PgI/
PgII ratio in Chinese patients.
359
Furthermore, a shift in the pre-
dominant bacterial communities, from Prevotella to
Streptococcus, has been identied in atrophic gastritis.
360
16S rRNA gene sequencing analysis showed that gastric
microbiota of patients with gastric cancer is dominated by dif-
ferent species of the genera Streptococcus (among them, the pre-
dominant species were S. mitis and S. parasanguinis),
Lactobacillus,Veillonella, and Prevotella.
361
The use of microarray G3 PhyloChip in patients with,
respectively, non-atrophic gastritis, intestinal metaplasia, and
gastric cancer, has shown that the gastric microbiota of patients
with gastric cancer displays signicantly lower diversity but a
higher abundance of members of the Pseudomonas genus than
that of patients with non-atrophic gastritis (with nine families
representing 50% of all operational taxonomic units); further-
more, both a trend towards the decrease of six taxa (two species
from TM7 phylum, two Porphyromonas species, Neisseria
species, and Streptococcus sinensis) and an opposite trend
towards the increase of two taxa (Lactobacillus coleohominis
and Lachnospiraceae) was observed from non-atrophic gastritis
to intestinal metaplasia to gastric cancer.
362
Another assessment of the gastric microbiota of patients with
chronic gastritis, intestinal metaplasia and gastric cancer, per-
formed through 16S rrDNA sequencing using a high-
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throughput sequencing platform (454 GS FLX Titanium), has
obtained totally different data, that includes a greater microbial
diversity, a relative increase of Bacilli and Streptococcaceae, and
a relative decrease of Helicobacteraceae in the gastric cancer
group than other groups.
363
In both studies, the analysis of
Unifrac distance between the three groups showed a clear separ-
ation between the gastric cancer group and the gastritis group,
whereas the intestinal metaplasia group overlapped with the two
groups.
These studies suggest that H. pylori may represent the main
but not the only microbial trigger for different gastric diseases,
and that microorganisms other than H. pylori may play a rele-
vant role in the development of complications in
H. pylori-related gastritis.
355 356 364
Statement 4: Non-H. pylori Helicobacter species can cause human gastric disease.
Level of evidence: 2c Grade of recommendation: B
Numerous Helicobacter species other than H. pylori have
been identied over recent years. Some of them have been
found in humans, including H. bilis,H. cinaedi, and H. fennel-
liae. Besides occasional associations with gastroenteritis,
365
infection with these and other enterohepatic Helicobacter
species have been associated with extraintestinal diseases, includ-
ing extrahepatic cholangiocarcinoma for H. bilis and H. hepati-
cus
366 367
and bacteraemia.
368
In addition to these
enterohepatic Helicobacter species, gastric non-H. pylori
Helicobacter species have also been detected in humans. These
patients have been reported to suffer from gastritis, peptic ulcer
disease, gastric cancer, and gastric mucosa-associated lymphoid
tissue lymphoma.
369374
Although these bacteria are often erro-
neously referred to as H. heilmannii, a number of similar but
distinct zoonotically important bacterial species are in fact
involved, including H. bizzozeronii,H. felis,H. heilmannii s.s.,
H. salomonis, and H. suis.
367 368 373 375379
Diagnosis of infec-
tion with one of these non-H. pylori Helicobacter species is not
always straightforward, in part due to their patchy colonisation
in the human stomach.
373 380
Statement 5:H. pylori eradication therapy can impair the healthy gut microbiota,
leading to short-term clinical consequences.
Level of evidence: 2c Grade of recommendation: B
Antibiotic treatments, including those for H. pylori eradica-
tion, are known to cause a number of short-term side effects.
Mouse models and human studies have shown that antibiotic
treatment can alter gut microbiota in terms of richness, diversity,
and composition.
381385
The recent improvement in diagnostic
technologies has allowed us to detect changes in gut microbiota
which occur after antibiotic therapy. In a recent study,
antibiotic-associated microbiota impairment was assessed by
high-throughput sequencing. Observed qualitative changes were
drug and dose dependent. The most relevant shifts involved,
respectively, Bacteroides, Bidobacterium, Clostridium,
Enterobacteriaceae, and Lactobacillus.
386
Probiotics may coun-
teract the harmful effects of antibiotics on gut microbiota.
384
Antibiotic-associated microbiota impairment can lead to a
number of clinical manifestations. The most common GI side
effects correlated with antibiotic therapy include diarrhoea,
nausea, vomiting, bloating, and abdominal pain
387
that may
lead to the discontinuation of treatment, with consequent risk
of therapeutic failure and/or development of antibiotic
resistance.
Furthermore, antibiotic administration is the main risk factor
for the development of C. difcile infection, an important cause
of morbidity and increased healthcare costs.
388
Statement 6:H. pylori eradication should be used with care in subjects with
undeveloped or unstable gut microbiota to avoid long-term clinical consequences.
Level of evidence: 2c Grade of recommendation: B
Evidence in animals and humans suggest that the alteration of
microbiota induced by antibiotics may be responsible for long-
term clinical consequences, that may persist after drug adminis-
tration.
381385
In a number of animal models, antibiotic therapy
was able to drive metabolic and weight changes, and to affect
intestinal expression of genes involved in the immune regula-
tion.
389 390
Several epidemiological studies have shown a posi-
tive association between exposure to antibiotics in early years of
life and increased risk of weight and fat gain.
391395
Therefore,
H. pylori eradication in subjects with unconsolidated gut micro-
biota (eg, during weaning) should be considered with care.
Statement 7: Antibiotic-based H. pylori eradication therapy can select
antibiotic-resistant components of gut microbiota.
Level of evidence: 2c Grade of recommendation: B
Overall, treatment with antibiotics increases the risk for selec-
tion of antibiotic resistant members of host gut microbiota. In par-
ticular, several studies showed that antibiotic-based eradication
therapy against H. pylori could select antibiotic-resistant compo-
nents of gut microbiota. Different triple therapies against
H. pylori, including omeprazole in combination with amoxicillin
and metronidazole or with clarithromycin and metronidazole, led
to the rise of resistant streptococci and staphylococci and to an
increase in the number of resistant Enterococcus species,
Enterobacteriaceae species, and Bacteroides species.
396
Results of a
cohort study have demonstrated that triple therapy consisting of
omeprazole, clarithromycin, and metronidazole selects for resist-
ance to macrolides within the gut microbiota of the host.
397
The
same eradication regimen was demonstrated to promote the selec-
tion of resistant enterococci and resistant strains of Staphylococcus
epidermidis, that persisted within the human gut microbiota for
several years after the end of antibiotic therapy.
398 399
Finally, a history of uoroquinolone-based therapies has been
shown to increase the risk for emergence of MRSA (methicillin-
resistant Staphylococcus aureus)
400 401
and extended specturm
beta lactamase (ESBL)-producing strains of E. coli or K.
pneumoniae.
402
Statement 8: Additional studies are required to address the long-lasting impact of
H. pylori eradication on the composition of gut microbiota.
Level of evidence: 5 Grade of recommendation: D
Currently, there is insufcient evidence on the effect of differ-
ent eradication regimens upon gut microbiome. Therefore, opti-
mally, mass eradication programmes should be implemented by
means of well-designed studies, including the evaluation of the
effects on gut microbiome. Other potential adverse events and
approaches to deal with such effects could also be addressed in
such studies.
Statement 9: Only certain probiotics have been shown to be effective in reducing
GI side effects caused by H. pylori eradication therapies. Specific strains should
be chosen only upon the basis of a demonstrated clinical efficacy.
Level of evidence: moderate Grade of recommendation: strong
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Several meta-analyses of RCTs have assessed the efcacy of
probiotic supplementation in reducing side effects associated
with antibiotic-based H. pylori eradication therapies, with
overall encouraging results.
403412
Some of these have focused
on the Lactobacillus genus, either including only studies investi-
gating Lactobacillus-containing probiotics or by subgroup ana-
lysis of pooled data, and have shown positive results,
403406 412
One meta-analysis highlighted the importance of a duration
exceeding 2 weeks of the probiotic treatment.
404
However
pooling data from studies which differ with regards to species/
strains, dosages and duration of probiotic therapies may lead to
misleading conclusions and therefore should be avoided.
413
The efcacy of adjuvant treatment with Saccharomyces bou-
lardii has been extensively investigated. In 2010, a rst
meta-analysis showed that S. boulardii reduced the risk or
overall adverse events (RR 0.46, 95% CI 0.3 to 0.7).
414
In
2015, the same group reported an updated meta-analysis, with
comparable results: S. boulardii decreased the risk and overall
adverse effects (RR 0.44, 95% CI 0.31 to 0.64).
415
Encouraging
data on other probiotics, such as Bacillus clausii, have emerged
from double-blind RCTs.
416
In conclusion, certain probiotics appear to be effective in
reducing adverse events related to H. pylori eradication therapy.
Several questions remain, including the effectiveness of specic
probiotic strains, dosages and duration of adjuvant probiotic
therapy, geographical differences, and the inuence of lifestyle
(eg, diet, alcohol or smoke consumption). These should be
addressed by future research.
Statement 10: Certain probiotics may have a beneficial effect on H. pylori
eradication.
Level of evidence: very low Grade of recommendation: weak
Probiotics may inhibit H. pylori through several mechanisms,
including the release of antimicrobial products or the competi-
tion with H. pylori for colonisation and survival. A number of
meta-analyses of RCTs have assessed the capacity of probiotics
to increase the efcacy of H. pylori eradication therapies, with
positive results.
403412
Nevertheless, in meta-analyses in which
sub-group analysis was performed, only certain strains main-
tained signicance, including different Lactobacillus
strains,
403 404 408 410
Bidobacterium strains,
403 404
and S.
boulardii.
404
These data highlight the impropriety of pooling the data from
studies investigating different probiotic species and strains.
413
In
two meta-analyses, S. boulardii was shown to increase the
H. pylori eradication rate, with, respectively, RRs of 1.13 (95%
CI 1.05 to 1.21)
414
and 1.11 (95% CI 1.06 to 1.17).
415
Despite these encouraging data, probiotics appear to increase
the H. pylori eradication rate by reducing side-effects related to
eradication therapy, rather than through direct effects on
H. pylori. Consequently, more data are denitely needed to
assess the direct efcacy of probiotics against H. pylori.
Author afliations
1
Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-
Guericke University Magdeburg, Magdeburg, Germany
2
Laboratoire de Bactériologie, Inserm U853, Université de Bordeaux, Bordeaux,
France
3
Faculty of Health Sciences, Trinity College, Dublin, Ireland
4
Department of Gastroenterology, Hospital Universitario de La Princesa, Instituto de
Investigación Sanitaria Princesa (IP), Madrid, Spain
5
Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas
(CIBEREHD), Madrid, Spain
6
Erasmus University Medical Center, Rotterdam, The Netherlands
7
General Inrmary Leeds, UK
8
Internal Medicine and Gastroenterology, University of Bologna Italy, Bologna, Italy
9
Gastroenterology, and Liver Unit, Internal Medicine, Roma, Italy
10
Nottingham, UK
11
Department of Medicine (111D), Michael E. DeBakey Veterans Affairs Medical
Center, Houston, Texas, USA
12
Department of Medicine, McMaster University, Hamilton, Canada
13
Hillcroft, Beaconseld, Buckinghamshire, UK
14
Department of Gastroenterology, McMaster University, Hamilton, Canada
15
Department of Gastroenterology, Henry Dunant Hospital, Athens, Greece
16
Department of Diagnostic Sciences, University of Padova, Padova, Italy
17
Regensburg, Germany
18
Medizinische Hochschule Hannover, Institut für Medizinische Mikrobiologie,
Hannover, Germany
19
Department of Medicine, Jichi Medical School, Tochigi, Japan
20
St George and Sutherland Clinical School, University of New South Wales, Sydney,
Australia
Acknowledgements We acknowledge the editorial assistance of
Mrs. D. Deutschländer.
Contributors L. Agreus (Sweden), L.P. Andersen (Denmark), J. Atherton (UK),
A. Axon (UK), F. Bazzoli (Italy), L. Coelho (Brazil), J.C. Delchier (France), F. Di Mario
(Italy), M. Dinis-Ribeiro (Portugal), E. El-Omar (UK), W. Fischbach (Germany),
B. Flahou (Belgium), K.M. Fock (Singapore), A. Gasbarrini (Italy), G. Gasbarrini
(Italy), G. Gensini (Italy), J. Gisbert (Spain), K.L. Goh (Malaysia), D.Y. Graham (USA),
R. Herrero (France), R. Hunt (UK), E.J. Kuipers (The Netherlands), L. Kupcinskas
(Kaunas), A. Lanas (Spain), M. Leja (Latvia), J.C. Machado (Portugal), V. Mahachai
(Thailand), P. Malfertheiner (Germany), F. Megraud (France), T. Milosavljevic (Serbia),
P. Moayyedi (Canada), J. Molina-Infante (Spain), Y. Niv (Israel), C. OMorain
(Ireland), A. Ristimaki (Finland), T. Rokkas (Greece), M. Rugge (Italy), M. Selgrad
(Germany), S. Suerbaum (Germany), K. Sugano ( Japan), B. Tepes (Slovenia), D. Vaira
(Italy), M. Vieth (Germany), W. You (China).
Funding This study was supported by an unrestricted grant of Malesci/Menarini
Foundation.
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.
REFERENCES
1 Malfertheiner P, Megraud F, OMorain CA, et al. Management of Helicobacter
pylori infectionthe Maastricht IV/ Florence Consensus Report. Gut
2012;61:64664.
2 Sugano K, Tack J, Kuipers EJ, et al. Kyoto global consensus report on Helicobacter
pylori gastritis. Gut 2015;64:135367.
3 Hunt RH, Camilleri M, Crowe SE, et al. The stomach in health and disease. Gut
2015;64:165068.
4 Robinson KA, Saldanha IJ, Mckoy NA. Frameworks for Determining Research Gaps
During Systematic Reviews. Agency for Healthcare Research and Quality (US),
2011.
5<