Article

Autoimmune gastritis: historical antecedents, outstanding discoveries, and unresolved problems.

Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
International Reviews Of Immunology (Impact Factor: 5.73). 08/2009; 24(1-2):1-29. DOI: 10.1080/08830180590884413
Source: PubMed

ABSTRACT The earliest recorded history of autoimmune gastritis can be traced to 1849 in London, when Thomas Addison described "a very remarkable form of anemia" later called pernicious (fatal) anemia (PA). This was followed by the recognition of a gastric mucosal defect suspected to have a nutritional basis, the discovery of the megaloblast that characterized the anemia, the insufficiency of a dietary extrinsic factor characterized as vitamin B12 (cobalamin), and a gastric-secreted intrinsic factor. Treatment with vitamin B12 proved curative. The link between PA and gastritis and atrophy was first confirmed histologically after immediate fixation of the stomach postmortem and later, in the 1940s, by peroral tube biopsy. The causes of gastritis remained enigmatic until the era of autoimmunity, when autoantibodies were detected first to gastric intrinsic factor and then to gastric parietal cells. Hints of a dichotomy in pathogenesis of gastritis were crystallized by the description in 1973 of Type A (Autoimmune) and Type B (later, Bacterial) gastritis. Clarification was enhanced by identification in Type A gastritis of the autoantigen of the parietal cell antibody, by the alpha and beta subunits of gastric H+/K+ ATPase, and by the highly informative experimental murine model of postneonatal thymectomy autoimmune gastritis, and in Type B of the causative role of gastric infection with Helicobacter pylori (H. pylori). A denouement will require a full understanding of (1) the origin and pathogenetic contribution of antibody to intrinsic factor; (2) the connection, if any, between H. pylori infection and Type A autoimmune gastritis; and (3) the genetic contributions to gastritis, whether due to autoimmunity or to H. pylori infection.

0 Bookmarks
 · 
112 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Among Western populations, the declining incidence of Helicobacter pylori infection coincides with a growing clinical impact of autoimmune gastritis. To describe the histological phenotype of autoimmune gastritis, also to test the prognostic impact of OLGA staging in the autoimmune setting. A single-institutional series (spanning the years 2003-2011) of 562 consecutive patients (M:F ratio: 1:3.7; mean age = 57.6 ± 14.4 years) with serologically confirmed autoimmune gastritis underwent histology review and OLGA staging. Helicobacter pylori infection was ascertained histologically in 44/562 cases (7.8%). Forty six biopsy sets (8.2%) featured OLGA stages III-IV; they included all four cases of incidental epithelial neoplasia (three intraepithelial and one invasive; three of these four cases had concomitant H. pylori infection). There were 230 (40.9%) and 139 (24.7%) cases, respectively, of linear and micro-nodular enterochromaffin-like cell hyperplasia; 19 (3.4%) type I carcinoids were detected. The series included 116 patients who underwent repeated endoscopy/biopsy sampling (mean time elapsing between the two procedures = 54 months; range 24-108). Paired histology showed a significant (P = 0.009) trend towards a stage progression [the stage increased in 25/116 cases (22%); it remained unchanged in 87/116 cases (75%)]. In autoimmune gastritis, the cancer risk is restricted to high-risk gastritis stages (III-IV), and is associated mainly with concomitant H. pylori infection. OLGA staging consistently depicts the time-dependent organic progression of the autoimmune disease and provides key information for secondary gastric cancer prevention strategies.
    Alimentary Pharmacology & Therapeutics 04/2012; 35(12):1460-6. · 4.55 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: It is now widely accepted that Helicobacter pylori may play a role in several extra-gastric diseases. In particular, H. pylori infection seems to be implicated in various autoimmune diseases. Many recent studies have shown a healing or an improvement in different autoimmune disorders after H. pylori eradication therapy in infected patients. The exact mechanisms behind this relationship remain under discussion, but molecular mimicry is a consistent hypothesis. This subject is particularly relevant taking into consideration the high prevalence of H. pylori infection, the existence of inexpensive and noninvasive diagnostic methods, as the urea breath test or the stool antigen test, and the low cost and toxicity of eradication treatment. If this connection becomes confirmed, it can change the diagnostic and therapeutic approach of some autoimmune diseases.
    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 04/2012; · 2.24 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Helicobacter pylorin (helikobakteeri) tartunta saadaan yleensä lapsena ja tauti jää tavallisesti pysyväksi ilman täsmähoitoa. Onnistunut hoito parantaa pysyvästi helikobakteerista aiheutuvan mahan haavataudin ja näyttää ehkäisevän mahalaukun pahanlaatuisten muutosten kehittymistä. Aloitimme Vammalassa terveyskeskuksessa toteutetun kansainvälisesti ainutlaatuisen väestöpohjaisen helikobakteeritulehduksen seulonta- ja hoito-ohjelman pilottitutkimuksella 1994. 1996 kaikki 15-40-vuotiaat ja 1997-2000 15- ja 45-vuotiaat vammalalaiset kutsuttiin verinäyteseulontaan. Yhteensä 4626 henkilöä (75% kutsutuista) osallistui seulontaan. Vasta-ainepositiivisille tarjottiin helikobakteeritulehduksen lopettava lääkekuuri. Toiminnan seurauksena helikobakteeritulehduksen esiintyvyyden laskettiin vähentyneen 12%:sta 4%:iin 15-40-vuotiaiden ikäryhmässä. Tutkimme myös helikobakteerivasta-ainepositiivisten ja -negatiivisten eroja sekä helikobakteeritulehduksen riskitekijöitä kyselytutkimuksella. Lapsuudenkodin asumisahtauden, äidin matalan koulutusasteen, tupakoinnin, alkoholinkäytön, huonojen asunto-olojen ja ylävatsavaivoista johtuvien sairauslomien todettiin liittyvän helikobakteeritulehdukseen monimuuttuja-analyysissa. Tutkimme seulontaohjelmassa käyttämiemme IgG- ja IgA-luokan helikobakteeri-vasta-ainetestien luotettavuutta eri ikäryhmissä ottaen huomioon atrofisen gastriitin esiintyvyyden. 561 kliinisin perustein gastroskopoidun potilaan aineistossa IgG-testi osoittautui erittäin herkäksi kaikissa ikäryhmissä (99%). Tarkkuus oli myös vanhemmissa ikäryhmissä hyvä (97-93%), kun atrofista gastriittia sairastavat suljettiin pois. IgA- ja CagA-helikobakteerivasta-aineiden on todettu liittyvän lisääntyneeseen mahahaava- ja mahasyöpäriskiin. Analysoimme 560 henkilön pariseeruminäytteet, jotka oli otettu kahden vuosikymmenen välein, ja totesimme, että IgA-vasta-aineiden esiintyvyyden lisääntyyminen iän myötä johtuu paitsi syntymäajankohdasta ja uusista infektioista myös IgA-vasta-ainetasojen kohoamisesta helikobakteeritulehduksen aikana. Selvitimme myös CagA-vasta-ainetasojen muuttumista analysoimalla seeruminäytteet, jotka oli otettu kahden vuosikymmenen välein. Totesimme, että samanaikaisesti kun helikobakteerin esiintyvyys väestössä on alentunut, erityisesti CagA-positiiviset infektiot ovat vähentyneet. Tutkimuksemme osoittaa, että Suomessa terveyskeskuksen yhteydessä voidaan toteuttaa näin laajamittainen seulonta- ja hoito-ohjelma, johon suomalaiset osallistuvat aktiivisesti. Nähtäväksi jää, kuinka paljon ohjelma kykeni vähentämään helikobakteeritulehdukseen liittyviä myöhäisseuraamuksia. Helicobacter pylori (H. pylori) causes a life long infection on the gastric mucosa which can lead to peptic ulcers and premalignant and malignant conditions. The infection, mainly acquired in childhood, rarely resolves spontaneously. Timely eradication of H. pylori improves dramatically the prognosis of peptic ulcer disease and seems to prevent subsequent gastric malignancies. We started in the primary health care practice in Vammala, Finland, a unique population-based, voluntary 'screen-and-treat' H. pylori pilot study in 1994. In 1996 the study was extended to include all inhabitants aged 15 to 40 years and in 1997-2000 all inhabitants aged 15 and 45 years; the participitation rate was 75%. Altogether 4626 subjects were screened for H. pylori infection using serology. All infected ones were offered eradication therapy. The eradication rates were 82.2% per-protocol and 71.9% in intention-to-treat analysis among the 3326 15 to 40-year-old participants in 1996. H. pylori seroprevalence rates were calculated to have decreased from 12% to 4% among them. Differences between H. pylori antibody-positive and -negative subjects and risk factors for H. pylori infection were studied using a questionnaire. In multivariate analysis, crowding in the childhood household, low education of the mother, smoking and alcohol consumption, unfavourable housing conditions, and sick leave due to dyspepsia were associated with H. pylori infection. We determined in different age-groups the accuracy of H. pylori IgG and IgA antibody tests used in the 'screen-and-treat' programme, with special emphasis on the presence of atrophic gastritis. In 561 consecutive adult patients who underwent gastroscopy for clinical indications the IgG test was highly sensitive (99%) in all age groups. The specificity was 99% in subjects aged 15- 49, and high also in those aged 50-64 and those aged 65 or older (97% and 93%, respectively), when patients with atrophic gastritis were excluded. Both IgA and CagA antibody responses during H. pylori infection have been found to be associated with an increased risk of peptic ulcers and gastric malignancies. By reanalysing paired serum samples collected with two decade’s interval from 560 subjects we found that the increase in the prevalence of IgA antibodies with age was due not only to the birth cohort phenomenon and seroconverters, but also to increasing IgA antibody levels during infection. The change in the prevalence of CagA antibodies was studied by reanalysing sera collected from 408 subjects in 1973 and from 503 subjects in 1994. The proportion of subjects infected with CagA+ H. pylori strains had declined faster than that of subjects infected with CagA- H. pylori strains, while the overall prevalence of H. pylori had declined.