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Citation: Burgard, M.; Litchinko, A.;
Meyer, J.; Toso, C.; Ris, F.; Delaune, V.
Outpatient Management Protocol for
Uncomplicated Diverticulitis: A
3-Year Monocentric Experience in a
Tertiary Hospital. J. Clin. Med. 2024,
13, 5920. https://doi.org/10.3390/
jcm13195920
Academic Editors: Andreas Neff and
Jun Kato
Received: 23 August 2024
Revised: 22 September 2024
Accepted: 2 October 2024
Published: 4 October 2024
Copyright: © 2024 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
Journal of
Clinical Medicine
Article
Outpatient Management Protocol for Uncomplicated
Diverticulitis: A 3-Year Monocentric Experience in a
Tertiary Hospital
Marie Burgard 1, *, Alexis Litchinko 1,2 , Jeremy Meyer 1, Christian Toso 1,3 , Frédéric Ris 1and
Vaihere Delaune 1,3
1Division of Digestive Surgery, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva,
Switzerland; alexis.litchinko@hcuge.ch (A.L.); jeremy.meyer@hcuge.ch (J.M.); christian.toso@hcuge.ch (C.T.);
frederic.ris@hcuge.ch (F.R.); vaihere.delaune@hcuge.ch (V.D.)
2Department of Surgery, Cantonal Hospital of Fribourg Chemin des Pensionnats 2/6,
1752 Villars-sur-Glâne, Switzerland
3Transplantation and Hepatology Laboratory, Geneva Medical University, Rue Michel Servet 1,
1206 Geneva, Switzerland
*Correspondence: marie.burgard@hcuge.ch; Tel.: +41-765817113
Abstract: Background/Objectives: The management of acute uncomplicated diverticulitis (AUD)
has shifted towards outpatient care in the last decade, challenging the traditional inpatient approach.
We aimed to analyze the safety and feasibility of a structured outpatient treatment pathway for
AUD in a tertiary hospital. Methods: We conducted a retrospective observational cohort analysis
of patients who underwent outpatient management for AUD at the Geneva University Hospitals
from 2019 to 2021. Patient demographics, selection criteria, treatment protocols, and outcomes
were analyzed. Results: Two-hundred and twenty patients were included in the outpatient cohort.
Four patients (1.8%) required hospitalization due to the failure of outpatient management, whereas
the majority of patients (116 patients, 98.2%) experienced a successful resolution of their symptoms
without hospitalization. In a univariate analysis, factors associated with treatment failure included
elevated white blood cell counts at admission (14 G/l vs. 10.6 G/l, p= 0.049) and the first follow-up
appointment, (10.7 G/l vs. 7.4 G/l, p= 0.011) and the presence of free air on their CT scan (25% vs.
2,3%, p= 0.033). In a multivariate analysis, the presence of free air was the only identified risk factor
for unsuccessful outpatient management (p= 0.05). We observed high rates of follow-up compliance
(99.1%). Conclusion: Under the condition of a warranted outpatient follow-up appointment and
with adequate selection criteria, outpatient management appears to be an effective approach for most
patients with AUD, emphasizing the importance of tailored therapeutic interventions and vigilant
clinical assessments for optimal outcomes.
Keywords: uncomplicated diverticulitis; outpatient management; treatment protocol
1. Introduction
Over the past decade, the paradigm of acute uncomplicated diverticulitis (AUD)
management has undergone substantial reevaluation. This shift has been propelled by an
expanding corpus of evidence suggesting that, for selected patients, outpatient management
(predominantly characterized by the administration of oral antibiotics) can be as safe
and effective as traditional inpatient care. Such outpatient strategies have demonstrated
comparable outcomes in terms of complication rates, hospital readmission frequencies,
and the necessity for surgical interventions, thereby challenging longstanding clinical
dogma [1–3].
Contemporary clinical guidelines reflect this paradigm shift, advocating for the out-
patient management of AUD in patients who do not exhibit sepsis, who are not immuno-
compromised, and who do not have contraindications such as an intolerance to oral intake
J. Clin. Med. 2024,13, 5920. https://doi.org/10.3390/jcm13195920 https://www.mdpi.com/journal/jcm
J. Clin. Med. 2024,13, 5920 2 of 10
or significant psychiatric or social impediments [
4
,
5
]. This patient-centric approach re-
quires a nuanced understanding of individual patient profiles and the complexities of their
conditions to ensure safe and effective treatment outside the hospital setting.
Parallel to the endorsement of outpatient management, there has been an emerging dis-
course surrounding the feasibility of non-antibiotic, observational, approaches for treating
AUD. Recent studies have illustrated the safety and efficacy of such strategies, presenting
them as viable alternatives that do not increase the risk of complications, necessitate hospi-
tal readmissions, or escalate to surgical interventions [
6
–
10
]. Despite the growing evidence
base, the clinical community remains divided, with a substantial number of physicians
expressing reservations about deviating from antibiotic treatments. This reluctance is
often attributed to concerns over insufficient surveillance and follow-up mechanisms in
outpatient settings, which could potentially compromise patient outcomes [11,12].
Moreover, the logistical challenges inherent in implementing non-antibiotic treatment
pathways in outpatient settings underscore the need for comprehensive, evidence-based
treatment algorithms. These protocols must account for rigorous patient selection criteria,
ensure meticulous follow-up appointments, and foster patient education to mitigate the
risks associated with treatment failures and complications [8,13–15].
Against this backdrop, our retrospective study seeks to meticulously analyze an
outpatient management protocol for AUD, with a specific focus on treatment efficacy,
failure rates, and patient compliance. By dissecting the outcomes associated with antibiotic
management strategies within an outpatient context, this study endeavors to enrich the
current understanding of AUD treatment modalities [
8
,
16
,
17
]. Furthermore, it aims to
critically assess the operationalization of outpatient care for AUD, examining the interplay
between patient selection, treatment efficacy, and follow-up compliance.
This investigation is based on the hypothesis that a well-structured outpatient man-
agement protocol for AUD can offer a safe, effective, and patient-centric alternative to
inpatient care. It contributes to the ongoing discourse by evaluating the practicalities of
implementing such a model in a real-world clinical setting, thereby offering insights that
could guide future clinical practice and policy formulation [5].
The objective of this study was to evaluate our clinical protocol in terms of outpatient
treatment failures, characterized by hospital admission, and their correlated risk factors.
Adherence to the designated follow-up regimen among the patients and the occurrence
rate of colorectal cancer within this demographic were analyzed as secondary outcomes.
2. Materials and Methods
This study is a retrospective, observational, cohort analysis conducted on a prospec-
tively collected database at the Geneva University Hospitals, Switzerland, from May 2019
to June 2022. The selection of this period was based on the date of implementation of
outpatient management of AUD in our institution and a safety analysis three years after
implementation.
All patients receiving a diagnosis of acute uncomplicated diverticulitis, warranting an
outpatient follow-up appointment, in the emergency department of the Geneva University
Hospitals were prospectively included in the database. Uncomplicated diverticulitis was
defined as the acute inflammatory state of a colonic segment, in the absence of any com-
plications such as free fluid, moderate to major pneumoperitoneum, fistula formation, or
abscesses, determined from the findings from computed tomography (CT) scans performed
in the emergency department. For classification and staging purposes, we employed the
Hinchey classification system [
18
]; Hinchey Ia was the classification used for AUD. These
patients were eligible for outpatient management through our specific institutional protocol.
Patients diagnosed with Hinchey Ia diverticulitis and a few amounts of extraluminal peri-
colic air were classified as “Hinchey Ia+”, based on the knowledge that extraluminal air can
constitute a risk factor for a disadvantaged short-term evolution [
19
]. Nevertheless, in the
absence of other risk factors, those patients were also eligible for outpatient management.
J. Clin. Med. 2024,13, 5920 3 of 10
Patients diagnosed with complicated diverticulitis, Hinchey Ib or higher, required
direct hospitalization. All individuals exhibiting any of the following risk factors, based on
existing studies [
1
,
20
], were also subjected to in-hospital treatment: lower gastrointestinal
hemorrhage, a C-reactive protein (CRP) level exceeding 200 mg/L, mental health disorders
or challenging social circumstances, an immunocompromised status, pregnancy, body
temperature above 38.5
◦
C, pain not controlled by over-the-counter painkillers, a long
weekend rendering close outpatient follow-up appointments impossible, or a recent episode
of acute diverticulitis (within the last 3 months). The data for these patients were not used
in this study. The outpatient treatment inclusion flowchart is illustrated in Figure 1.
J. Clin. Med. 2024, 13, x FOR PEER REVIEW 3 of 10
term evolution [19]. Nevertheless, in the absence of other risk factors, those patients were
also eligible for outpatient management.
Patients diagnosed with complicated diverticulitis, Hinchey Ib or higher, required
direct hospitalization. All individuals exhibiting any of the following risk factors, based
on existing studies [1,20], were also subjected to in-hospital treatment: lower gastrointes-
tinal hemorrhage, a C-reactive protein (CRP) level exceeding 200 mg/L, mental health dis-
orders or challenging social circumstances, an immunocompromised status, pregnancy,
body temperature above 38.5 °C, pain not controlled by over-the-counter painkillers, a
long weekend rendering close outpatient follow-up appointments impossible, or a recent
episode of acute diverticulitis (within the last 3 months). The data for these patients were
not used in this study. The outpatient treatment inclusion flowchart is illustrated in Figure
1.
The outpatient treatment protocol (Figure 2) started with a single dose of intravenous
antibiotics administered in the emergency department, followed by a 7-day regimen of
wide spectrum oral antibiotics. Due to local resistant bacterial strains, the intravenous reg-
imen was usually comprised of Ceftriaxone/Metronidazole, and the oral regimen of
Ciprofloxacin/Metronidazole. Additionally, patients received level I analgesics (paraceta-
mol and non-steroid anti-inflammatory drugs if needed). An initial follow-up appoint-
ment for the clinical and laboratory evaluation was conducted at the Division of Digestive
Surgery between 24 and 72 h after the initial consultation. A subsequent follow-up ap-
pointment for the clinical and laboratory assessment was scheduled 48 h after the antibi-
otic regimen’s conclusion. Furthermore, all patients lacking a recent colonoscopy (within
the last 3 years) were advised to undergo this procedure at the 6-week mark, with a sub-
sequent clinical consultation at the Division of Digestive Surgery to review the findings.
Figure 1. Inclusion flowchart.
Figure 1. Inclusion flowchart.
The outpatient treatment protocol (Figure 2) started with a single dose of intravenous
antibiotics administered in the emergency department, followed by a 7-day regimen of
wide spectrum oral antibiotics. Due to local resistant bacterial strains, the intravenous
regimen was usually comprised of Ceftriaxone/Metronidazole, and the oral regimen of
Ciprofloxacin/Metronidazole. Additionally, patients received level I analgesics (paraceta-
mol and non-steroid anti-inflammatory drugs if needed). An initial follow-up appointment
for the clinical and laboratory evaluation was conducted at the Division of Digestive
Surgery between 24 and 72 h after the initial consultation. A subsequent follow-up ap-
pointment for the clinical and laboratory assessment was scheduled 48 h after the antibiotic
regimen’s conclusion. Furthermore, all patients lacking a recent colonoscopy (within the
last 3 years) were advised to undergo this procedure at the 6-week mark, with a subsequent
clinical consultation at the Division of Digestive Surgery to review the findings.
J. Clin. Med. 2024,13, 5920 4 of 10
J. Clin. Med. 2024, 13, x FOR PEER REVIEW 4 of 10
Figure 2. Outpatient treatment protocol.
Should there be an adverse clinical or laboratory outcome during follow-up appoint-
ments, the protocol mandated a control CT scan and/or immediate hospital admission for
further intravenous antibiotic administration. Patients unable to continue with oral med-
ication were also admied for inpatient care.
Medical and imaging data for the selected patients were retrospectively extracted.
Key variables of interest included demographic data, clinical presentation including pain
score, vital parameters, and biological markers at initial presentation, as well as biological
markers at follow-ups and the result of the colonoscopy. Data confidentiality was main-
tained throughout the study, with all patient information being anonymized prior to anal-
ysis. Continuous variables were expressed as means with standard deviations; when var-
iables did not follow a normal distribution, we used medians with the interquartile range.
Continuous variables were analyzed using an independent t-test. Categorical variables
were expressed as a number and percentage; they were analyzed using a Chi-squared test
or Fisher’s exact test where appropriate. Univariate and multivariate Cox proportional
hazard regression analyses were conducted to analyze the predictive factors of unsuccess-
ful outpatient management. The results were expressed as hazard ratios with 95% confi-
dence intervals. The statistical significance was defined as a two-tailed p-value ≤ 0.05.
A data analysis was performed using the Statistical Package for Social Sciences, ver-
sion 29.0 (SPSS, IBM, Armonk, NY, USA.) We performed a complete-case analysis. No
data were missing for patient demographics except for BMI (143/220 missing). At initial
presentation, biological markers were complete and vital parameters were missing in
2/220 patients. At follow-up appointments, visit biological markers were missing in 5/220
patients.
All participants provided their wrien consent via an institutional consent form for
further use of data for research purposes; this study received approval from the regional
ethics board (CCER), BASEC-ID 2023-00661.
3. Results
Two hundred and twenty patients received outpatient management for acute diver-
ticulitis. Among these patients, only four individuals (1.8%) required subsequent hospi-
talization during their follow-up period, while the vast majority (98.2%) experienced a
successful resolution of symptoms under outpatient care. Causes leading to hospital ad-
mission or failure of outpatient management encompassed a lack of clinical improvement
with oral antibiotic administration (n = 1), upper gastrointestinal bleeding (n = 1), abscess
formation requiring radiological drainage (n = 1), and elevated CRP levels coupled with
persistent abdominal pain (n = 1). Notably, none of the patients required emergency sur-
gical intervention.
The demographic characteristics of the patient cohort are described in Table 1; both
groups were comparable, albeit with a slight trend towards high blood pressure as a
comorbidity in patients who were hospitalized during follow-up appointments (p = 0.07).
Figure 2. Outpatient treatment protocol.
Should there be an adverse clinical or laboratory outcome during follow-up appoint-
ments, the protocol mandated a control CT scan and/or immediate hospital admission
for further intravenous antibiotic administration. Patients unable to continue with oral
medication were also admitted for inpatient care.
Medical and imaging data for the selected patients were retrospectively extracted.
Key variables of interest included demographic data, clinical presentation including pain
score, vital parameters, and biological markers at initial presentation, as well as biolog-
ical markers at follow-ups and the result of the colonoscopy. Data confidentiality was
maintained throughout the study, with all patient information being anonymized prior to
analysis. Continuous variables were expressed as means with standard deviations; when
variables did not follow a normal distribution, we used medians with the interquartile
range. Continuous variables were analyzed using an independent t-test. Categorical vari-
ables were expressed as a number and percentage; they were analyzed using a Chi-squared
test or Fisher’s exact test where appropriate. Univariate and multivariate Cox proportional
hazard regression analyses were conducted to analyze the predictive factors of unsuccessful
outpatient management. The results were expressed as hazard ratios with 95% confidence
intervals. The statistical significance was defined as a two-tailed p-value ≤0.05.
A data analysis was performed using the Statistical Package for Social Sciences, version
29.0 (SPSS, IBM, Armonk, NY, USA.) We performed a complete-case analysis. No data were
missing for patient demographics except for BMI (143/220 missing). At initial presentation,
biological markers were complete and vital parameters were missing in 2/220 patients. At
follow-up appointments, visit biological markers were missing in 5/220 patients.
All participants provided their written consent via an institutional consent form for
further use of data for research purposes; this study received approval from the regional
ethics board (CCER), BASEC-ID 2023-00661.
3. Results
Two hundred and twenty patients received outpatient management for acute diver-
ticulitis. Among these patients, only four individuals (1.8%) required subsequent hos-
pitalization during their follow-up period, while the vast majority (98.2%) experienced
a successful resolution of symptoms under outpatient care. Causes leading to hospital
admission or failure of outpatient management encompassed a lack of clinical improve-
ment with oral antibiotic administration (n= 1), upper gastrointestinal bleeding (n= 1),
abscess formation requiring radiological drainage (n= 1), and elevated CRP levels coupled
with persistent abdominal pain (n= 1). Notably, none of the patients required emergency
surgical intervention.
The demographic characteristics of the patient cohort are described in Table 1; both
groups were comparable, albeit with a slight trend towards high blood pressure as a
comorbidity in patients who were hospitalized during follow-up appointments (p= 0.07).
A high proportion of patients in both groups had previously experienced at least one
episode of acute diverticulitis (81% and 75%, respectively, p= 0.93).
J. Clin. Med. 2024,13, 5920 5 of 10
Table 1. Demographic characteristics of the patient cohort.
Outpatient
n= 216
Hospitalization
n= 4 p
Age, years, median (range) 57 (25–88) 56 (37–64) 0.404
Gender, n(%)
F
M
116 (53.7%)
100 (46.3%)
1 (25%)
3 (75%)
0.254
BMI, kg/m2, mean, (SD) 28.7 (±5.1) 26.5 (±7.1) 0.565
Comorbidities, n(%)
HTA (%)
Diabetes
70 (32.4%)
14 (6.5%)
3 (75%)
0
0.073
0.599
Tobacco use, n(%) 44 (20.4%) 1 (25%) 0.909
History of surgery for
diverticulitis, n(%) 10 (4.6%) 0 0.660
Previous episodes, n(%)
0
1
2
3
4
5
6
7
8
9
41 (19.2%)
112 (52.3%)
27 (12.6%)
16 (7.5%)
12 (5.6%)
1 (0.5%)
3 (1.4%)
0
1 (0.5%)
1 (0.5%)
1 (25%)
2 (25%)
1 (25%)
1 (25%)
0
0
0
0
0
0
0.931
Episodes in the last 2 years, n(%)
0
1
2
3
4
176 (81.5%)
27 (12.5%)
9 (4.2%)
3 (1.4%)
1 (0.5%)
4 (100%)
0
0
0
0
0.925
Time since last episode, weeks
mean (SD) 160.1 (±167.8) 198 (±59.4) 0.753
n= number, F = female, M = male, BMI = body mass index, kg = kilograms, m = meters, SD = standard deviation,
and HTA = arterial hypertension.
The duration of symptoms and initial vital sign measurements were comparable
across both patient cohorts, as shown in Table 2. However, patients experiencing unsuc-
cessful outpatient treatment exhibited significantly elevated white blood cell (WBC) counts
both at admission (14 G/l vs. 10.6 G/l, p= 0.05) and at the first follow-up appointment
(10.7 G/l vs. 7.4 G/l, p= 0.05) compared to those with successful treatment outcomes.
While C-reactive protein (CRP) levels at admission were similar between groups, individu-
als with unsuccessful outpatient management demonstrated a trend towards higher CRP
values at the first follow-up appointment (100 mg/L vs. 54 mg/L, p= 0.07). Additionally,
the presence of free air on their CT scan was markedly higher in patients experiencing
unsuccessful outpatient treatment (25% vs. 2.3%, p= 0.006).
Univariate analyses found an elevated white blood cell count at admission (p= 0.049)
and at the first follow-up visit (p= 0.011), as well as the presence of proximal free air
(p= 0.033), which was associated with unsuccessful outpatient treatment. In the multivari-
ate analysis, the presence of free proximal air was an independent factor associated with an
unsuccessful outpatient treatment (p= 0.05), as shown in Table 3.
J. Clin. Med. 2024,13, 5920 6 of 10
Table 2. Initial vital signs, blood sample, and imaging parameters.
Outpatient
n= 216
Hospitalization
n= 4
p
Time since beginning of
symptoms, days, mean (SD)
2.7 (±2.1) 2.25 (±1.5) 0.668
HR, BPM, mean
(SD)
89.7 (±14.8) 80 (±14.1) 0.196
Mean BP, mmHG mean (SD) 103.8 (±13.9) 96.3 (±14.5) 0.284
Temperature, ◦C, mean (SD) 36.9
(±0.7)
37.4
(±0.7)
0.288
Pain score, mean (SD) 4.3
(±2.5)
5.8
(±2.1)
0.225
Lc, mean (SD)
- At admission
- At first follow-up
appointment
10.6 (±3.4)
7.4 (±2.3)
14 (±1.6)
10.7 (±2.1)
0.05
0.05
CRP, mean (SD)
- At admission
- At first follow-up
appointment
66.5 (±43.9)
54.2 (±48.9)
73.5 (±60.1)
99.5 (±93.9)
0.755
0.073
Affected colon segment, n(%)
- Right colon
- Transverse
- Left colon
- Sigmoid
18 (8.3%)
1 (0.5%)
34 (15.7%)
163 (75.5%)
0
0
0
4 (100%)
0.731
Free air, n(%)
- Proximal
- Distant
5 (2.3%)
5 (100)
0
1 (25%)
1 (100%)
0
0.006
n= number, SD = standard deviation, HR = heart rate, BMP = beats per minute, BP = blood pressure,
mmHG = millimeter mercury, C = Celsius, Lc = leucocyte, and CRP = C-reactive protein.
Table 3. Univariate and multivariate Cox regression of factors associated with unsuccessful outpatient
treatment.
Univariate pMultivariate p
Time since beginning of
symptoms, days
0.87 (0.47–1.61) 0.667
HR, BPM 0.94 (0.87–1.03) 0.203
Mean BP, mmHG 0.96 (0.89–1.04) 0.289
Temperature, ◦C 1.17 (0.23–6.08) 0.850 1.07 (0.38–3.00) 0.902
Pain score 1.32 (0.83–2.11) 0.238
Lc
- At admission
- At first follow-up
appointment
1.42 (0.98–1.79)
1.71 (1.13–2.59)
0.049
0.011
1.16 (0.8–1.69)
1.60 (0.97–2.55)
0.436
0.092
CRP
- At admission
- At first follow-up
appointment
1.01 (0.98–1.03)
1.01(0.99–1.03)
0.754
0.093
1.01 (0.975–1.03)
1.02 (0.98–1.01)
0.939
0.898
J. Clin. Med. 2024,13, 5920 7 of 10
Table 3. Cont.
Univariate pMultivariate p
Affected colon segment
- Right colon
- Transverse
- Left colon
- Sigmoid
0.00
0.00
0.00
Ref
0.99
1.00
0.98
Free air
- No free air
- Proximal free air
Ref
14.1
(1.24–159.89)
0.033 11.72
(0.67–206.28)
0.048
HR = heart rate, BPM = beats per minute, BP = blood pressure, mmHg = millimeter mercury, C = Celsius,
Lc = leucocyte, CRP = C-reactive protein, and Ref = reference.
Follow-up appointments were adhered to by a significant majority of the patients.
Two hundred and eighteen individuals (99.1%) attended the initial follow-up visit; comple-
tion of the second follow-up appointment was achieved by 202 patients (94%).
Of the total patient cohort, 107 individuals (49%) underwent a follow-up colonoscopy.
Reasons for the non-completion of the colonoscopy were a recent normal examination
within the past three years in 29% of patients, and the reason was undocumented in 71%
of patients. A colonoscopic evaluation unveiled an underlying rectal neuroendocrine
neoplasia in one patient (0.9%). Non-malignant polyps were found in 20/107 individuals
(19%); there were no colorectal adenocarcinomas.
4. Discussion
The management of acute uncomplicated diverticulitis (AUD) has evolved signifi-
cantly in recent years, reflecting a shift towards outpatient-based strategies. Our study
adds to the growing body of evidence supporting the efficacy of outpatient management
for AUD, when close monitoring is set in place. The overwhelming majority of patients
in our cohort (98.2%) experienced a successful resolution of their symptoms without the
need for hospitalization, and none needed urgent surgery, aligning with previous research
highlighting the feasibility and safety of outpatient care [
17
]. This underscores the potential
of outpatient pathways to alleviate healthcare burdens and costs associated with inpatient
admissions, while maintaining favorable patient outcomes.
The success of outpatient management hinges on meticulous patient selection and
adherence to structured treatment protocols. Our study adhered to stringent criteria for
identifying candidates suitable for outpatient care, excluding individuals with complicated
diverticulitis or significant risk factors necessitating hospitalization. Our selection of criteria
justifying inpatient treatment was based on previously published papers [
1
,
20
]. Adherence
to this protocol was associated with favorable outcomes, highlighting the importance of
standardized approaches in optimizing patient care.
Despite the overall success of our outpatient management, a small subset of patients
required subsequent hospitalization, necessitating an exploration of factors associated with
treatment failure. Our analysis identified the presence of pericolic free air on their CT scan
as a potential independent predictor of unsuccessful outpatient treatment. These findings
corroborate previous research [
21
], suggesting a correlation between free air and disease
severity in AUD, underscoring the utility of risk stratification and therapeutic decision
making. Although several studies have shown a low failure rate of non-operative treatment
for patients presenting with free pericolic air [
22
–
24
], to our knowledge, studies about the
feasibility of outpatient treatment in this patient group are lacking. The updated WSES
guidelines propose a non-operative strategy with antibiotic treatment for this specific group
of patients, without, however, recommendations about inpatient or outpatient treatment [
5
].
In agreement with our findings, Costi et al. showed that many surgeons still promote
inpatient treatment for patients with extraluminal free air [25].
J. Clin. Med. 2024,13, 5920 8 of 10
Central to the success of outpatient management are robust follow-up and surveillance
mechanisms to monitor treatment responses and detect complications promptly. Our
study demonstrated high rates of follow-up compliance among the patients, with the
vast majority attending scheduled appointments. This underscores the importance of
patient involvement in their proposed health management method, and healthcare provider
communication in facilitating the continuity of care and early intervention when necessary.
The inclusion of routine colonoscopy in our follow-up protocol enabled the detection of one
underlying neoplastic lesion (0.9%). This small percentage of underlying neoplastic lesions
in uncomplicated diverticulitis is consistent with several studies [
4
,
16
,
26
,
27
]. A tailored
approach regarding an endoscopy to avoid complications and limit costs therefore seems
reasonable [8,28–30].
While our findings support the feasibility of outpatient management for AUD, several
challenges and areas for future investigation warrant consideration. The logistic complexi-
ties of implementing outpatient protocols, including patient education, resource allocation,
and interdisciplinary coordination, pose practical barriers to widespread adoption. In
their recent snapshot study, Dalby et al. showed a higher adherence to current guidelines
concerning outpatient management for AUD in centers that had previously participated in
the AVOD trial, rather than in non-participating centers [
16
,
31
]. These findings underline
that there are still barriers to changing the “that’s how we’ve always done it” mentality in
many hospitals. Moreover, the optimal duration and composition of antibiotic regimens, as
well as the role of adjunct therapies such as probiotics or dietary modifications, remain the
subjects of ongoing debate and warrant further exploration. Additionally, the long-term
outcomes and recurrence rates following outpatient management merit continued scrutiny,
particularly in the context of the increased incidence of acute diverticulitis in a younger
population and patients’ quality of life [32].
Our study is not without limitations. As a retrospective analysis, it is inherently subject
to selection bias and data incompleteness, although we reached a high rate of completeness
of follow-up data. Furthermore, the generalizability of our findings may be limited by the
specific patient population and institutional practices represented in our cohort. Finally,
more than half our patients did not have evidence of a follow-up colonoscopy in our files,
limiting the fortuitous discovery of colorectal cancer in this population. We, therefore,
cannot generalize that patients with uncomplicated diverticulitis have a 0.9% risk of cancer;
this number could be over- or under-estimated.
Future prospective studies incorporating larger, more diverse patient populations
and longer follow-up periods are needed to validate our findings and elucidate additional
factors influencing treatment outcomes.
The high patient compliance in our study encourages us to pursue a non-antibiotic
outpatient treatment regimen and analyze the long-term results.
5. Conclusions
Outpatient management appears to be an effective approach for the majority of pa-
tients presenting with acute uncomplicated diverticulitis, with a high success rate in this
highly protocoled setting. However, careful monitoring is warranted, as a small proportion
of patients may require subsequent hospitalization, particularly those with evidence of free
air on their CT scan. These findings underscore the importance of vigilant clinical assess-
ments to optimize outcomes in the management of acute diverticulitis in the outpatient
setting. Further studies exploring risk stratification and optimal follow-up strategies are
warranted to refine patient care and outcomes in this clinical context.
Author Contributions: Conceptualization: V.D. and J.M.; Methodology: V.D. and J.M.; Formal
Analysis: M.B.; Data Curation: V.D., M.B. and A.L.; Original Draft Preparation: M.B. and A.L.;
Writing—Review and Editing: V.D., J.M., F.R. and C.T.; and Supervision: V.D. All authors have read
and agreed to the published version of the manuscript.
Funding: This research received no external funding.
J. Clin. Med. 2024,13, 5920 9 of 10
Institutional Review Board Statement: This study was conducted according to the guidelines of the
Declaration of Helsinki and approved by the Ethics Committee (CCER), BASEC-ID 2023-00661 on 20
June 2023.
Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.
Data Availability Statement: Data generated or analyzed during this study are available from the
corresponding author upon reasonable request.
Conflicts of Interest: The authors disclose no conflicts of interest.
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