Pouchitis: an evolving clinical enigma--a review

Normal Ileal Mucus Is Inadequate for Epithelial Protection in Ileal Pouch Mucosa

BACKGROUND

Clinical, nonspecific pouchitis is common after restorative proctocolectomy for ulcerative colitis, but its cause is unknown. A possible lack of protection for the ileal mucosa in its role as a reservoir for colonic-type bacteria may be the missing piece in defining the causes of pouchitis.

OBJECTIVE

The study aimed to review the causes of pouchitis and introduce the hypothesis that inadequate mucus protection in the pouch, combined with a predisposition to abnormal inflammation, is the most common cause of nonspecific pouchitis.

DATA SOURCES

Review of PubMed and MEDLINE for articles discussing pouchitis and intestinal mucus.

STUDY SELECTION

Studies published from 1960 to 2023. The main search terms were "pouchitis," and "intestinal mucus," whereas Boolean operators were used with multiple other terms to refine the search. Duplicates and case reports were excluded.

MAIN OUTCOME MEASURES

Current theories about the cause of pouchitis, descriptions of the role of mucus in the physiology of intestinal protection, and evidence of the effects of lack of mucus on mucosal inflammation.

RESULTS

The crossreference of "intestinal mucus" with "pouchitis" produced 9 references, none of which discussed the role of mucus in the development of pouchitis. Crossing "intestinal mucus" with "pouch" resulted in 32 articles, combining "pouchitis" with "barrier function" yielded 37 articles, and "pouchitis" with "permeability" yielded only 8 articles. No article discussed the mucus coat as a barrier to bacterial invasion of the epithelium or mentioned inadequate mucus as a factor in pouchitis. However, an ileal pouch produces a colonic environment in the small bowel, and the ileum lacks the mucus protection needed for this sort of environment. This predisposes pouch mucosa to bacterial invasion and chronic microscopic inflammation that may promote clinical pouchitis in patients prone to an autoimmune response.

LIMITATIONS

No prior studies address inadequate mucus protection and the origin of proctitis. There is no objective way of measuring the autoimmune tendency in patients with ulcerative colitis.

CONCLUSIONS

Studies of intestinal mucus in the ileal pouch and its association with pouchitis are warranted.

Nonbloody Diarrhea but Not Significant Weight Loss at Diagnosis Is Associated with the Development of Denovo Crohn's Disease After Ileal Pouch-anal Anastomosis for Ulcerative Colitis

BACKGROUND

Denovo Crohn's disease (CD) develops in 5% to 10% of patients after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) leading to increased morbidity and rates of pouch failure. Initial nonbloody diarrhea and weight loss at diagnosis are independent risk factors for a change in diagnosis from UC to CD in nonsurgical patients. We investigated whether these features were risk factors for denovo CD in a longitudinal cohort of patients with UC undergoing IPAA.

METHODS

Prospective profiles of patients with UC undergoing IPAA followed over a 22-year period by 1 surgeon were analyzed. Denovo CD was diagnosed when mucosal inflammation (5 or more ulcers) involved the small bowel mucosa proximal to the ileal pouch any time after surgery and/or when a pouch fistula or other perianal complication developed more than 3 months after ileostomy closure. Patients with inflammatory bowel disease unclassified, acute pouchitis, chronic pouchitis, and those lost to follow-up were excluded from analysis. Cox regression analysis was performed for statistical significance.

RESULTS

Of the 199 study patients included in the analysis, denovo CD developed in 42 patients (21%). Patients who developed denovo CD had an increased incidence of nonbloody diarrhea (n = 12; 29%) compared with patients who had no evidence of pouch inflammation (n = 25; 16%) (P = 0.03). In contrast, the incidence of weight loss was not significantly increased in patients with denovo CD (n = 7; 17%) compared with patients who never had pouch inflammation (n = 16; 10%) (P = 0.12).

CONCLUSIONS

Initial nonbloody diarrhea is associated with denovo CD after IPAA. This association warrants close consideration before surgery.

Use of Biologics in Pouchitis: A Systematic Review

Data about the effectiveness of biologics, including anti-tumor necrosis factor (TNF) therapy and anti-integrin strategies, in antibiotic refractory pouchitis or Crohn's disease-associated pouch complications are sparse. We performed a systematic review of the literature in Medline and Web of Science. All English language publications and meeting abstracts describing patients with pouchitis treated with anti-TNF or anti-integrin therapies were included. We identified a total of 17 papers and 2 abstracts, most of these retrospective case series, including a total of 192 patients treated either with infliximab (n=140) or adalimumab (n=52). No reports were found for anti-integrin therapies or other anti-TNF agents such as certolizumab pegol or golimumab. Because of the heterogeneity of the studies, small numbers of patients, differing cotreatments, and subjective outcome definitions, the exact efficacy of these biological therapies cannot be assessed in a combined fashion. Overall infliximab appears to have good clinical effectiveness in selected patients achieving up to 80% short-term and around 50% long-term response, whereas the few data available for adalimumab are not sufficient to draw valid conclusions. Larger prospectively collected multicenter data with clearly defined inclusion criteria and outcomes are necessary to better define the clinical value of anti-TNF therapy in patients with antibiotic refractory pouchitis or Crohn's-like complications of the pouch.

Serum alpha-1 antitrypsin: a noninvasive marker of pouchitis

BACKGROUND

Patients with ulcerative colitis undergoing total proctocolectomy with ileal pouch-anal anastomosis may develop pouchitis. Alpha-1-antitrypsin (AAT) is an acute phase reactant produced mainly by hepatocytes, but also locally in the gut. Data on noninvasive biomarkers of pouchitis are scarce.

METHODS

To identify biomarkers that correlate with pouch inflammation, ulcerative colitis pouch patients were prospectively recruited and underwent clinical, endoscopic, and histologic evaluations. The Pouchitis Disease Activity Index (PDAI) was calculated, and pouchitis was defined by a score ≥7. Serum and fecal AAT, C-reactive protein (CRP), fecal calprotectin, ferritin and albumin levels were measured.

RESULTS

Seventy-one ulcerative colitis pouch patients (mean age 43.8 ± 8.3 yr, 50.7% males) were included. The main indication for ileal pouch-anal anastomosis was intractable colitis (83.1%). Median serum AAT level (183.0 mg/dL, 155.1-232.0) was significantly higher in patients with a PDAI ≥7 compared with those with a PDAI <7 (167.6 mg/dL, 151.0-181.0) (P = 0.03). Serum AAT, CRP, and fecal calprotectin levels significantly correlated with PDAI scores: r = 0.583, P < 0.001; r = 0.584, P < 0.001; and r = 0.606, P = 0.001, respectively. Serum AAT and CRP levels correlated significantly (r = 0.650, P < 0.001), as did serum AAT and fecal calprotectin levels (r = 0.663, P < 0.001). Fecal AAT levels did not correlate with any tested biomarker. Receiver operating characteristic analysis demonstrated sensitivity, specificity, and positive predictive value of 55.6%, 100%, and 100%, respectively, for diagnosing pouchitis at a serum AAT cutoff level of 189 mg/dL.

CONCLUSIONS

Serum AAT is a specific noninvasive biomarker of pouchitis. AAT levels correlate with disease activity and CRP and calprotectin levels.

Quality of life, continence and frequency of pouchitis following laparoscopic versus open colectomy and ileal pouch-anal anastomosis: an Irish perspective

BACKGROUND

This study aims to assess quality of life outcomes, continence, rates of pouchitis and predictors of pouchitis for patients undergoing laparoscopic versus open three-stage ileal pouch-anal anastomosis (IPAA) surgery in our institution.

METHODS

Forty-two patients having had three-stage (IPAA) surgery were identified. One was excluded as they had undergone pouchectomy. A postal questionnaire followed by telephone contact was undertaken. The questionnaire was based on The Gastrointestinal Quality of Life Index (GIQLI) and Wexner/Cleveland Clinic Faecal Incontinence Symptom Severity Scoring Systems.

AIMS

Our aim was to assess morbidity, quality of life, incidence of pouchitis and continence following restorative panproctocolectomy and IPAA.

RESULTS

Thirty-five patients completed the response. The median age at colectomy of our patient population was 32 years. 57 % were male and 43 % were female. 54.3 % of cases were carried out laparoscopically. 8/19 patients who had laparoscopic surgery had pouchitis (42.1 %) versus 9/16 patients who had open surgery (56.3 %). The median Wexner score was 0. Nine patients (25.7 %) had a GIQLI score that was within or above the range reported for healthy controls. The rate of complications was 31.7 % for emergency cases and 25.7 % for elective cases. The rate of pouchitis in this group was 48.5 %. Overall pelvic sepsis rate was 12.8 %.

CONCLUSIONS

Ileal pouch-anal anastomosis is a successful and well-tolerated procedure with 94 % of patients opting to have the surgery again. Preliminary results do not show any significant difference in the incidence of pouchitis following laparoscopic surgery.

Drivers of cost after surgical and medical therapy for chronic ulcerative colitis: a nested case-cohort study in Olmsted County, Minnesota

BACKGROUND

We previously reported the costs associated with surgery for chronic ulcerative colitis in the Olmsted County population and found that direct medical costs after surgery were significantly reduced compared with before surgery. However, in that study, costs associated with chronic medical therapy for ulcerative colitis were not assessed in nonsurgical patients.

OBJECTIVE

To gain insight into the drivers of costs of treatment for chronic ulcerative colitis, we assessed direct costs after surgical and medical therapy in 120 patients in the Rochester Epidemiology Project database.

METHODS

A cohort of 60 patients who recovered from surgery for ulcerative colitis from 1988 to 2006 were 1:1 matched by age, sex, and referent year to medically managed patients. Direct health care costs were estimated from an institutional database, and observed cost differences over a 2-year period were calculated. Statistical significance was assessed by paired t tests and bootstrapping; mean costs are adjusted 2009 constant dollars.

RESULTS

Two-year direct health care costs in the surgical and medical cohorts were $10,328 vs $6,586 (p = 0.19). In the surgical cohort, Brooke ileostomy patients were observed to have higher costs than patients with ileal pouches ([INCREMENT]$8187, p = 0.04), and after ileal pouch, pouchitis was associated with increased costs ([INCREMENT]$12,763, p < 0.01). In the medical cohort, disease extent ([INCREMENT]$6059, p = 0.04) but not disease severity was associated with increased costs.

LIMITATIONS

This study was limited by the relatively small population size and by its performance in a county with a tertiary referral center.

CONCLUSIONS

Before the introduction of biologic therapies for ulcerative colitis, patients were observed to have similar health care costs after surgical and medical therapy. In medically treated patients, disease extent was associated with increased costs, whereas in surgically treated patients, permanent ileostomy and pouchitis were observed to be associated with increased costs.

Matrix metalloproteinases in the restorative proctocolectomy pouch of pediatric ulcerative colitis

AIM: To investigate matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in pouch mucosa of pediatric onset ulcerative colitis (UC).

METHODS: In this cross-sectional study, 28 patients with pediatric onset UC underwent ileal pouch biopsy 13 years (median) after proctocolectomy. Expression of MMPs-3, -7, -8, -9, -12 and -26 and TIMPs-1, -2 and -3 in samples was examined using immunohistochemichal methods, and another biopsy was used to evaluate the grade of histological inflammation. Two investigators independently graded the immunohistochemical specimens in a semiquantitative fashion, using a scale marking staining intensity as follows: 0 = less than 20 positive cells; 1 = 20-50 positive cells; 2 = 50-200 positive cells; 3 = over 20 positive cells. Fecal calprotectin and blood inflammatory markers [serum C-reactive protein (CRP) and erythrocyte sedimentation rate] were determined during a follow-up visit to examine correlations between these markers and the expression of MMPs and TIMPs.

RESULTS: Of the 28 patients with pediatric onset UC, nine had not experienced pouchitis, whereas thirteen reported a single episode, and six had recurrent pouchitis (≥ 4 episodes). At the time of the study, six patients required metronidazole. In all of the others, the most recent episode of pouchitis had occurred over one month earlier, and none were on antibiotics. Only four samples depicted no sign of inflammation, and these were all from patients who had not had pouchitis. Two samples were too small to determine the grade of inflammation, but both had suffered pouchitis, the other recurrent. No sample depicted signs of colonic metaplasia. Most pouch samples showed expression of epithelial (e) and stromal (s) MMP-3 (e, n = 22; s, n = 20), MMP-7 (e, n = 28; s, n = 27), MMP-12 (e, n = 20; s, n =24), TIMP-2 (e, n = 23; s, n = 23) and MMP-3 (e, n = 23; s, n = 28) but MMP-8 (e, n = 0; s, n = 1), MMP-9 (e, n = 0; s, n = 9) and MMP-26 (e, n = 0; s, n = 3) and TIMP-1 (n = 0, both) were lacking. In samples with low grade of inflammatory activity, the epithelial MMP-3 and MMP-7 expression was increased (r = -0.614 and r = -0.472, respectively, P < 0.05 in both). MMPs and TIMPs did not correlate with the markers of inflammation, fecal calprotectin, erythrocyte sedimentation rate, or CRP, with the exception of patients with low fecal calprotectin (< 100 μg/g) in whom a higher expression of epithelial MMP-7 was found no differences in MMP- or TIMP-profiles were seen in patients with a history of pouchitis compared to ones with no such episodes. Anastomosis with either straight ileoanal anastomosis or ileoanal anastomosis with J-pouch did depict differences in MMP- or TIMP-expression.

CONCLUSION: The expression of MMPs pediatric UC pouch in the long-term shares characteristics with inflammatory bowel disease, but inflammation cannot be classified as a reactivation of the disease.

The long-term clinical course of pouchitis after total proctocolectomy and IPAA for ulcerative colitis

BACKGROUND

Pouchitis is the most common long-term complication after restorative total proctocolectomy and IPAA for ulcerative colitis.

OBJECTIVE

We examined the incidence, clinical aspects, and long-term outcome of patients with idiopathic pouchitis.

DESIGN

This study was a retrospective review of medical records.

PATIENTS

Included in the study were 284 patients with ulcerative colitis who underwent a total proctocolectomy and IPAA.

MAIN OUTCOME MEASURES

We evaluated the cumulative risk and long-term outcome of pouchitis including the duration of disease, pattern of relapse, and responsiveness to antibiotic therapy.

RESULTS

Sixty-four patients developed idiopathic pouchitis. The cumulative risk was 10.7% at 1 year, 17.2% at 2 years, 24.0% at 5 years, and 38.2% at 10 years. At their first pouchitis episode, 45 patients had acute pouchitis, 19 patients had chronic pouchitis, and all patients received antibiotic therapy with oral ciprofloxacin and/or metronidazole. The efficacy of the therapy was 96.6% initially. Forty-five patients had antibiotic-responsive pouchitis, 17 patients had antibiotic-dependent pouchitis, and 2 patients had antibiotic-refractory pouchitis at their first episode. Whereas 20 of 45 patients (44.4%) with initially acute pouchitis experienced 2 or more relapses, 16 of 19 patients (84.2%) with initially chronic pouchitis had 2 or more relapses. After taking into account the relapses, the number of patients with antibiotic-responsive pouchitis decreased from 45 to 40, the number with antibiotic-dependent pouchitis increased from 17 to 20, and the number with antibiotic-refractory pouchitis increased from 2 to 4. Among the 4 patients with antibiotic-refractory pouchitis, 3 patients had Clostridium difficile-associated pouchitis.

LIMITATIONS

This study was retrospective.

CONCLUSION

The patients with chronic pouchitis at the first episode tend to have a higher incidence of relapse. In some patients, the responsiveness to antibiotic therapy changes during follow-up. When patients with pouchitis do not respond to standard antibiotic therapy, then the occurrence of C difficile infection should be considered.

Pharmacotherapy for acute pouchitis

OBJECTIVE

To review the current literature concerning the medical treatment of acute and chronic pouchitis.

DATA SOURCES

MEDLINE and International Pharmaceutical Abstracts were searched (both 1965-February 2011) using the following terms: pouchitis, Crohn's, ulcerative colitis, diagnosis, prophylaxis, and treatment. Bibliographies from key articles were also searched, and all pertinent articles were reviewed.

STUDY SELECTION AND DATA EXTRACTION

All available primary literature published in English on treatment for pouchitis was considered, with controlled trials receiving highest priority.

DATA SYNTHESIS

Pouchitis occurs in up to 50% of ileal pouch-anal anastomosis (IPAA) patients with inflammatory bowel disease within 10 years of the procedure. Symptoms include abdominal pain, bloating, and fecal incontinence with frequent diarrhea. The diagnosis of pouchitis is usually made based on symptoms as well as endoscopic and histologic findings. Treatment of acute pouchitis includes antimicrobials such as ciprofloxacin, metronidazole, and rifaximin. If these fail, limited data suggest that oral budesonide, mesalamine, or infliximab may be effective treatments. Surgical revision may be necessary if medical treatments fail. Emerging evidence suggests that the probiotic compound VSL#3 may be effective in preventing the recurrence of pouchitis.

CONCLUSIONS

Pouchitis is a common complication of IPAA surgery. The strongest data suggest that antimicrobial therapy is an effective first-line treatment for acute pouchitis, and VSL#3 may be effective for prevention of recurrence.

Desulfovibrio bacterial species are increased in ulcerative colitis

BACKGROUND

Debate persists regarding the role of Desulfovibrio subspecies in ulcerative colitis. Combined microscopic and molecular techniques enable this issue to be investigated by allowing precise enumeration of specific bacterial species within the colonic mucous gel. The aim of this study was to combine laser capture microdissection and quantitative polymerase chain reaction to determine Desulfovibrio copy number in crypt-associated mucous gel in health and in acute and chronic ulcerative colitis.

METHODS

Colonic mucosal biopsies were harvested from healthy controls (n = 19) and patients with acute (n = 10) or chronic (n = 10) ulcerative colitis. Crypt-associated mucous gel was obtained by laser capture microdissection throughout the colon. Pan-bacterial 16S rRNA and Desulfovibrio copy number/mm were obtained by polymerase chain reaction at each locus. Bacterial copy numbers were interrogated for correlation with location and disease activity. Data were evaluated using a combination of ordinary linear methods and linear mixed-effects models to cater for multiple interactions.

RESULTS

Desulfovibrio positivity was significantly increased in acute and chronic ulcerative colitis at multiple levels within the colon, and after normalization with total bacterial signal, the relative Desulfovibrio load was increased in acute colitis compared with controls. Desulfovibrio counts did not significantly correlate with age, disease duration, or disease activity but interlevel correlations were found in adjacent colonic segments in the healthy control and chronic ulcerative colitis groups.

CONCLUSION

The presence of Desulfovibrio subspecies is increased in ulcerative colitis and the data presented suggest that these bacteria represent an increased percentage of the colonic microbiome in acute ulcerative colitis.