Fecal α₁arantitrypsin clearance in patients with inflammatory bowel disease

We evaluated fecal clearance of α₁-antitrypsin (α₁AT) as a method of detecting and quantitating intestinal protein loss in patients with inflammatory bowel disease. We investigated α₁AT clearance (C_α1-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. α₁AT was measured in stool (72-h collections) and serum by radial immunodiffusion, and the clearance was calculated. The mean C_α1-ATin patients with inflammatory bowel disease was significantly (p < 0.05) higher than that of the controls. C_α1-ATin the former patients was inversely related to the serum albumin level (p < 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_α1-ATfrom only ileal to diffuse small intestinal disease involvement. We conclude that in patients with inflam-matory bowel disease, fecal clearance of α₁-AT is a useful method for quantitating intestinal protein loss, and that moderate rectal bleeding does not affect the C_α1-ATdetermination.