Collagenous colitis: a prospective trial of prednisolone in six patients.

In a prospective study, the clinicopathological effect of prednisolone was evaluated in six patients with collagenous colitis. Prednisolone was associated with a significant decrease in stool frequency. However, the effect was transitory, since the diarrhoea recurred when prednisolone treatment was discontinued. There was a trend toward a diminished inflammatory response in the post-treatment biopsies, but the thickness of the collagen band remained unchanged, except in one patient. Until the results of further studies are available, we recommend that treatment with prednisolone be restricted to periods of acute diarrhoeal episodes.