PAF-acether and acetylhydrolase in stool of patients with Crohn's disease.

PAF-acether (PAF) is a phospholipid mediator with potent biological effects on the digestive tract. We report the presence of PAF in stool of patients with active Crohn's disease (39.1 +/- 13.5 ng/g of stool, mean +/- SEM, N = 19) and its absence in patients with irritable bowel syndrome with diarrhea and diarrhea with malabsorption. Fecal PAF acetylhydrolase activity was higher (P less than 0.04) in patients with Crohn's disease as compared to patients with irritable bowel syndrome with diarrhea and diarrhea with malabsorption. We also report a solid-phase extraction of fecal PAF using silica minicolumns, which yielded results highly correlated with those obtained with a high-performance liquid chromatography method (r = 0.86, P less than 0.001, N = 16). These findings may allow us to implicate PAF in the onset and perpetuation of digestive tract inflammatory symptoms observed during Crohn's disease. They would warrant to investigate the influence of various therapeutic agents, including PAF antagonists, on fecal PAF levels during inflammatory digestive ailments.