Editor,—The paper by Ramsden and colleagues1 showed no evidence that colonic wall thickness differs in children with cystic fibrosis who take high or low strength preparations of pancreatic enzymes, or the product they used previously. They found that, on average, colonic wall thickness was greater in children with cystic fibrosis than in controls, which confirms the observations made by Oppenheimer and Esterley2 more than 20 years ago (many years before any of the present enzyme formulations existed).

Despite these negative results, the authors seem to have accepted the hypothesis (which has little or no published evidence to support it) that there is a connection between colonic thickening, fibrosing colonopathy, and methacrylic acid copolymer Eudragit L30 D55. They state that this copolymer “in high doses has a toxic effect on the gut of animals”, but give no reference for this statement. They also say that no association has been found between fibrosing colonopathy and Creon 25000 (which does not contain Eudragit) in the United Kingdom epidemiological study of fibrosing colonopathy.3 I was the chairman of that study, but, for the following reasons, was unhappy with the investigation and its published presentation. Firstly, the selection and inclusion of …