Comment in Eur J Gastroenterol Hepatol. 1999 Sep;11(9):997-9. BACKGROUND: Rheumatological and other extraintestinal manifestations (EIM) are common in inflammatory bowel disease (IBD) but also seem to occur in patients after restorative proctocolectomy and formation of an ileo-anal pouch. The prevalence and significance of these symptoms have not been established in this clinical context. OBJECTIVE: To evaluate prospectively the prevalence and associations of EIM of IBD in ulcerative colitis (UC) patients following restorative proctocolectomy (RP) and to compare the findings to those in a control group of familial adenomatous polyposis (FAP) patients who had undergone similar surgery. METHODS: One hundred and twenty-three (97 UC and 26 FAP) consecutive patients with ileal pouches undergoing long-term follow-up underwent an assessment of rheumatological symptoms and signs, similarly of other EIM; each underwent pouch endoscopy and biopsy. RESULTS: Symptoms in the joints were reported in 30 (31%) of UC patients compared to two (8%) FAP patients (P = 0.02). Twenty-four (80%) of the affected patients had a polyarticular arthralgia affecting primarily the knees, and small joints of the hands. Clinical findings and radiological investigations were almost exclusively normal. Most patients had mild symptoms, with only 12 of the 30 reporting interference with daily life. The presence of symptoms in the joints was not associated with a positive family history for IBD or other EIM, the presence of non-rheumatological EIM or the presence of pouchitis. Histological scores of pouch inflammation did not differ between those with and without symptoms of the joints. CONCLUSIONS: A mild polyarticular arthralgia, similar to that associated with active IBD, is common following RP and may commence after surgery. It is not associated with the presence of pouch inflammation.