Relations between Pancreatic Enzyme Outputs and Malabsorption in Severe Pancreatic Insufficiency

To investigate the functioning reserve capacity of the exocrine pancreas, we studied the relations of steatorrhea and creatorrhea to lipase and trypsin outputs in 17 patients with chronic pancreatitis and 33 healthy subjects. A standard diet was given, and stools were collected for 48 hours. Total enzyme outputs in response to duodenal perfusion of essential amino acids (78 mM) and intravenously administered cholecystokinin-pancreozymin (0.25 U per kilogram per minute) were compared in patients and in healthy subjects. Steatorrhea was not observed until lipase output was 10 per cent or less of normal; similarly, creatorrhea occurred only when trypsin outputs were less than 10 per cent of normal. These relations demonstrate the large reserve capacity for enzyme secretion by the exocrine pancreas and explain the often late development of steatorrhea and creatorrhea in chronic pancreatitis. (N Engl J Med 288:813–815, 1973)