[Show abstract][Hide abstract] ABSTRACT: Ileal inflammation in ulcerative colitis can occur as backwash ileitis or prestomal ileitis. After restorative proctocolectomy (RPC), ileal inflammation may be present in the pouch (pouchitis) but inflammation proximal to the pouch in the neo-terminal ileum, so called pre-pouch ileitis (PI), has also been observed. As pouchitis is increasingly common and PI can mimic it, our aim was to characterize this condition.
A review of prospectively collected data on 571 inflammatory bowel disease patients undergoing follow-up after RPC in a single centre over 22 years was performed. The histology of biopsy material was reviewed and staining for colonic mucosal phenotypic changes was undertaken. It was not routine practice to prospectively assess all patients for pre-pouch ileitis when the database was constructed.
Of 19 patients with inflammation of the pre-pouch neo-terminal ileum (NTI) identified three had Crohn's disease and one a NSAID stricture. The remaining 15 had a characteristic diffuse inflammation extending from the NTI-pouch junction proximally: pre-pouch ileitis. The inflammation extended proximally for up to 50 cm. Fistula formation was seen in only one. Seven (47%) of 15 had pouchitis but only two had suffered backwash ileitis pre-operatively. Seven responded to medical therapy and four to surgery. The histological appearances including staining for colonic phenotypic change were similar in PI and pouchitis.
Pre-pouch ileitis is uncommon. As the patients' previous diagnosis of UC was confirmed and there was no radiological or histological evidence of Crohn's disease, PI appears to have a distinct pathogenesis from Crohn's disease.
[Show abstract][Hide abstract] ABSTRACT: In familial adenomatous polyposis, the long-term risk of pouch polyposis and potential for pouch cancer are unknown. Our aim was to evaluate prospectively the prevalence, nature, and etiology of pouch ileal adenomas with that of nonpouch ileal adenomas in familial adenomatous polyposis.
Sixty patients with familial adenomatous polyposis pouch, 47 familial adenomatous polyposis patients with ileorectal anastomosis, and 20 younger patients with familial adenomatous polyposis who had prophylactic colectomy were examined with videoendoscopy.
Adenomatous polyps were found in the pouches of 34 patients (57 percent). A total of 362 polyps were identified (range, 0-50 per patient). A logistic regression model confirmed that there was a significant association between the increasing age of the patient and the presence of pouch adenomas (P < 0.02) and the length of follow-up since pouch surgery (P < 0.05). There was no apparent relationship between the development of pouch adenomas and the severity of either colonic or duodenal polyposis and there were no clear genotype or phenotype correlations. Most polyps were tubular adenomas with mild dysplasia, but 11 patients had more advanced histology, including two patients with large villous adenomas. Nonpouch ileal mucosa was spared from visually observed adenomas, with only 1 of 48 (2 percent) patients with ileorectal anastomosis adenomas and 0 of 20 (0 percent) younger, precolectomy patients having terminal ileal adenomas. However, microadenomas were present on random biopsy in 4 percent to 5 percent of nonpouch ileum.
The risk of pouch cancer in familial adenomatous polyposis is unclear, but follow-up periods since surgery remain relatively short. Long-term endoscopic surveillance of familial adenomatous polyposis pouches is thus recommended along with evaluation of potential therapeutic options for pouch adenomas.
Diseases of the Colon & Rectum 05/2005; 48(4):816-23. · 3.34 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Studies of adenomatous polyposis coli (APC) mutations in familial adenomatous polyposis (FAP) have focused on large bowel disease. It has been found that: 1) germline APC mutations around codon 1300 are associated with severe colorectal polyposis; 2) somatic APC mutations in colorectal tumors tend to cluster approximately between codons 1250 and 1450; and 3) patients with germline mutations close to codon 1300 tend to acquire somatic mutations (second hits) in their colorectal polyps by allelic loss, whereas the tumors of other FAP patients have truncating second hits. Using new and published data, we have investigated how germline and somatic APC mutations influence the pathogenesis of upper gastrointestinal polyps in FAP. We have compared the results with those from colorectal disease. We found that somatic mutations in upper gastrointestinal polyps cluster approximately between codons 1400 and 1580. Patients with germline APC mutations after codon 1400 tend to show allelic loss in their upper gastrointestinal polyps; the tumors of other patients have truncating somatic mutations after codon 1400. Finally, patients with germline mutations after codon 1400 tend to have more severe duodenal polyposis (odds ratio, 5.72; 95% confidence interval, 1.13 to 28.89; P = 0.035). Thus, in both upper gastrointestinal and colorectal tumors, a specific region of the APC gene is associated with severe disease, clustering of somatic mutations, and loss of the wild-type allele. However, the region concerned is different in upper gastrointestinal and colorectal disease. The data suggest that loss of all APC SAMP repeats is probably necessary for duodenal and gastric tumorigenesis in FAP, as it is in colonic tumors. Compared with colonic tumors, however, retention of a greater number of beta-catenin binding/degradation repeats is optimal for tumorigenesis in upper gastrointestinal FAP.
American Journal Of Pathology 07/2002; 160(6):2055-61. · 4.60 Impact Factor