To evaluate the outcome of medical therapy for pouchitis.

MEDLINE was searched from 1966 to December 1997; the keywords were listed. Reference lists of potentially relevant papers were manually searched. Proceedings from the American Gastroenterology Association, the American Society of Colon and Rectal Surgery, and the British Society of Gastroenterology were manually searched from 1965 to 1997 to identify unpublished trials.

Study designs of evaluations included in the review

Randomised controlled trials (RCTs) that evaluated medical therapy for pouchitis were included. Primary studies included those of parallel and cross-over design. Single patient placebo controlled trials were excluded.

Specific interventions included in the review

The following interventions were studied: metronidazole 1200 mg/day orally for 7 days; oral placebo; oral probiotic bacteria (VSL-3) 6 g/day for 9 months; bismuth carbomer foam enemas administered nightly for 3 weeks; placebo enemas administered nightly; suppository containing L-glutamine 1g in a polyethylene glycol base administered twice daily for 3 weeks; and suppository containing sodium butyrate 40mmol in a polyethylene glycol base administered twice daily for 3 weeks.

Participants included in the review

Adult patients aged 18 years or greater with pouchitis were included. Pouchitis was variably defined by solely clinical criteria, clinical criteria in combination with endoscopic and histological criteria or the Pouchitis Disease Activity Index (PDAI: see Other Publications of Related Interest). Subjects had active pouchitis (mild to severe symptoms or PDAI score =/> 7), or remission (absence of symptoms or PDAI score <7), and either acute pouchitis (symptom duration </= 4 weeks) or chronic (symptom duration > 4 weeks).

Outcomes assessed in the review

Clinical improvement or remission as defined in each study was assessed. Definitions varied across studies.

How were decisions on the relevance of primary studies made?

Three authors reviewed potentially relevant articles in an independent unblinded fashion.

The authors did not state that they assessed validity.

Three authors independently extracted data onto specially designed data extraction forms. The proportion of patients who had clinical improvement in each treatment arm was derived from life tables, survival curves, or where possible, by calculating life tables from the data provided. data were extracted on an intention to treat basis.

How were the studies combined?

The studies were combined in a narrative review.

How were differences between studies investigated?

Results were reported by intervention.

Four RCTs were included (112 patients).

Oral metronidazole for 7 days (1 double blind, placebo controlled cross-over RCT, 13 patients with chronic active pouchitis): Significant decrease in stool frequency of at least 3 stools/24 hours with metronidazole. OR = 12.34 (95% CI: 2.23, 64.95). Absolute risk reduction = 0.64; Relative risk reduction = 8.11; Number needed to treat = 1.56.

Oral probiotic therapy for 9 months (1 double blind placebo controlled RCT, 40 patients with chronic pouchitis in remission): reduced relapse rate measured by increase of 2 or more points in clinical part of PDAI with probiotic therapy. OR = 15.33 (95% CI: 4.51, 52.14). Absolute risk reduction = 0.85; Number needed to treat = 1.18.

Bismuth carbomer foam enemas for 3 weeks (1 double blind placebo controlled RCT, 40 patients with active chronic pouchitis): no difference in response rates (defined as decrease of 3 or more points in PDAI score) between bismuth suppositories and placebo. OR = 1.00 (95% CI: 0.29, 3.42). Absolute risk reduction = 0.00; Relative risk reduction = 1.00.

Glutamine vs butyrate suppositories for 3 weeks (1 double blind comparative RCT, 19 patients who had discontinued suppressive medical therapy for chronic pouchitis): no difference between suppositories in remission defined clinically. OR = 2.75 (95% CI: 0.48, 15.94). Absolute risk reduction = 0.27; Relative risk reduction = 1.82; Number needed to treat = 3.7.

Metronidazole is an effective therapy for active chronic pouchitis. Bismuth carbomer enemas are not effective therapy for active chronic pouchitis. Oral probiotic therapy with VSL-3 is an effective therapy for maintaining remission in patients with chronic pouchitis in remission. There is no difference in maintenance of symptomatic remission in patients with chronic pouchitis treated with glutamine versus butyrate suppositories, and it is unknown whether glutamine and butyrate are equally effective or ineffective.

The aims and inclusion criteria were stated. The literature search included attempts to locate unpublished trials. Methods used to select primary studies and extract data were described. Data was extracted on an intention to treat basis. Some relevant details of primary studies and results were clearly presented. The discussion does advise that additional controlled trials are required.

Fuller information of the primary studies such as validity would have been helpful.

Given the lack of validity assessment and conclusions for each therapy being based on a small number of patients treated often for short periods of time in one trial, caution is advised when considering the authors conclusions.

Practice: The authors consider that it is reasonable to treat pouchitis with antibiotics and perhaps probiotic therapy but that bismuth cannot be advocated.

Research: The authors consider that additional randomised double blind, placebo controlled, dose ranging trials are needed to determine the efficacy of empiric medical therapies currently being used in patients with pouchitis. Such trials should incorporate clear definitions of treatment indications such as active acute or chronic pouchitis and maintenance of remission for acute or chronic pouchitis.

1. Sandborn WJ, Tremaine WJ, Batts KP et al. Pouchitis following ileal pouch-anal anastomosis: a pouchitis disease activity index. Mayo Clin Proc 1994;69:409-15.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.