Graded experimental acute pancreatitis: monitoring of a renewed rabbit model focusing on the production of interleukin-8 (IL-8) and CD11b/CD18.

OBJECTIVE: To establish and monitor a rabbit model of graded severity of acute pancreatitis to test the hypothesis that interleukin-8 (IL-8) and the adhesion molecule complex CD11b/CD18 are involved in the development of systemic complications in severe acute pancreatitis. METHODS: Acute pancreatitis induction in rabbits by duct ligation with or without infusion of 5.0% or 0.5% chenodeoxycholic acid or 0.9% saline. Control animals underwent laparotomy. The animals were monitored biochemically, histologically and immunohistochemically. RESULT: Increased serum levels of IL-8, tumour necrosis factor alpha (TNF-alpha), amylase and lipase were found in the chenodeoxycholic acid groups when compared with the saline, duct-ligated or control groups. Leukopenia, hypocalcaemia, and hyperglycaemia were marked in the 5.0% chenodeoxycholic acid group as compared to the saline, duct-ligated and control groups. Histologically, the 5.0% chenodeoxycholic acid group manifested a significant degree of pancreatic necrosis and neutrophil infiltration. The lungs of these animals showed acute lung injury and a significant up-regulation of CD11b/CD18. IL-8 was produced in pancreatic acinar and ductal cells. A significantly large output of ascitic fluid was seen in the 5.0% chenodeoxycholic acid group. CONCLUSION: The rabbit models of acute pancreatitis are reliable in that enzymatic and histological evidence of acute pancreatitis with or without systemic complications developed. IL-8 is produced locally in pancreatic acinar and ductal cells and significantly increased in peripheral blood during severe but not mild pancreatitis. The expression of the adhesion molecule complex CD11b/CB18 is significantly increased in lung tissue during severe acute pancreatitis with acute lung injury. IL-8 and CD11b/CB18 are involved in the pathogenesis of severe acute pancreatitis but not of mild oedematous pancreatitis.

Prospective study of prevalence and endoscopic and histopathologic characteristics of duodenal polyps in patients submitted to upper endoscopy.

BACKGROUND: Retrospective studies of duodenal polyps have shown a prevalence of 0.3%-1.5% in patients referred to upper endoscopy, and histopathologic classifications have been inconsistent. METHODS: A prospective consecutive study was carried out in 584 patients referred to diagnostic upper endoscopy. Symptoms were registered on a questionnaire, endoscopic and histopathologic findings on standard forms. The same pathologist evaluated all biopsy specimens. RESULTS: Twenty-seven patients had polyps in the first and/or second part of the duodenum, for a prevalence 4.6%. Sixteen polyps were either inflammatory (nine polyps) or ectopic gastric mucosa (seven polyps). Both of these polyp types were practically always non-solitary, sessile, small, and located in the duodenal bulb. Seven polyps were covered by normal mucosa, three being endoscopically typical lipomas. Two polyps were adenomas (0.4% of all the patients and 7% of the polyps), and both were found in the descending part. One hyperplastic polyp of the gastric type and one case of fibrosis were found. CONCLUSIONS: 1) Duodenal polyps are found in 4.6% of patients referred to upper endoscopy and should therefore be looked for. 2) Multiple, small polyps in the duodenal bulb are always benign and need neither biopsy nor treatment (in patients with familial polyposis biopsy is recommended). 3) In the descending duodenum polyps are rare, but a substantial number of them are adenomas. Biopsy is therefore mandatory in this localization.