We evaluated fecal clearance of
alpha 1-antitrypsin (alpha 1-AT) as a method of detecting and quantitating intestinal
protein loss in patients with
inflammatory bowel disease. We investigated alpha 1-AT clearance (C alpha 1-AT) in 14 patients (seven with
Crohn's disease, seven with
ulcerative colitis) and in 10 children with
gastrointestinal disorders and normal
serum albumin values who served as controls. The
inflammatory bowel disease patients were analyzed for nutritional status, intestinal absorption, disease activity and distribution, and presence or absence of rectal
bleeding. alpha 1-AT was measured in stool (72-h collections) and serum by radial immunodiffusion, and the clearance was calculated. The mean C alpha 1-AT in patients with
inflammatory bowel disease was significantly (p less than 0.05) higher than that of the controls. C alpha 1-AT in the former patients was inversely related to the
serum albumin level (p less than 0.001), but not to disease activity, medications, absorption, nutritional status, or moderate rectal
bleeding. In the patients with
Crohn's disease there was a trend to increased C alpha 1-AT from only ileal to diffuse small
intestinal disease involvement. We conclude that in patients with
inflammatory bowel disease, fecal clearance of alpha 1-AT is a useful method for quantitating intestinal
protein loss, and that moderate rectal
bleeding does not affect the C alpha 1-AT determination.