Steatorrhea and pancreatic insufficiency in Shwachman syndrome.

Fat absorption was assessed on two or more occasions in 12 of 14 patients with Shwachman syndrome. Of 11 children who initially had steatorrhea, 6 were subsequently found to have normal fat excretion. In 10 of these 11 patients the last estimate was smaller than the initial estimate after an interval of 0.3-12.7 yr. The most dramatic improvement occurred under 4 yr of age but improvement appeared to continue over a more extended period where sufficient follow-up was available. All patients had pronounced pancreatic insufficiency as tested by duodenal drainage corrected by nonabsorbable marker under stimulation with cholecystokinin and secretin. Pancreatic lipase secretion was assessed in 3 patients with steatorrhea and 5 without steatorrhea (73% of the surviving patients) using a sensitive assay which used maximum stimulation with colipase. Pancreatic lipase secretion was less than 2% of normal mean secretion in the steatorrheic patients and ranged from 3.7% to 13.6% in the patients without steatorrhea. These results indicate that fat absorption improves in the majority of patients with Shwachman syndrome and appears to be associated with marginal improvement in pancreatic lipase secretion. Due to the occult nature of bowel complaints in older patients, the diagnosis may be overlooked unless careful screening for pancreatic function takes place.