[Diffuse primary fat replacement of the pancreas: an unusual cause of steatorrhea].

Diffuse and primitive fat replacement of the exocrine pancreas is a rare cause of exocrine pancreatic insufficiency in adults. We report two adult patients with chronic diarrhoea and steatorrhea whose morphologic abnormalities revealed diffuse fat replacement of the pancreas. Tomodensitometry detected diffuse characteristic abnormalities with fat intermixed with normal pancreatic lobules or a "vanishing pancreas". In one patient, magnetic resonance imaging and echo-endoscopy suggested abnormalities. Administration of pancreatic extracts improved symptoms.