Changes in intestinal transit time after proctocolectomy assessed by the lactulose breath test

After proctocolectomy with ileal pouch-anal anastomosis (IPAA) patients hav e increased stool frequency and intermittently use antidiarrheal medication . In addition to other factors, gastrointestinal transit time (MTT) could i nfluence stool frequency. The aim of this study was to investigate how MTT changes after IPAA and to study whether MTT has an influence on daily stool frequency. In a prospective trial MTT was investigated with the lactulose breath test in 12 patients undergoing surgery for chronic ulcerative coliti s (CUC) or familial adenomatous polyposis coli (FAPC) at different stages: before proctocolectomy, after IPAA with loop ileostomy, and 3 months and 1 year after ileostomy closure. MTT nas also measured in 12 patients with IPA A, 12 patients with subtotal colectomy and ileorectal anastomosis (IRA), an d 8 patients with conventional proctocolectomy and Brooke ileostomy (CPC) s everal years after surgery. Twelve healthy volunteers served as controls, B efore IPAA MTT was prolonged in CUC versus FAPC and controls. After restora tion of gut continuity MTT was markedly accelerated. After 1 year MTT was s toned again, though values before proctocolectomy and those in controls wer e not reached. Several years after surgery MTT was significantly prolonged in IPAA and IRA versus controls. In CPC, MTT could not be determined by lac tulose breath test. Stool frequency showed an inverse correlation to MTT in IP;IA. In conclusion, this study shows that orocecal and oropouch transit are accelerated in the early postoperative period after (procto)colectomy b ut prolonged in the long-term course. Adaptation of the small bowel takes l onger than 1 year. Impairment of stool frequency may be partly due to this adaptation.