(51)CrEDTA colonic permeability and therapy response in patients with ulcerative colitis

Orally administered Cr-51-labelled ethylenediaminetetraacetic acid ((51)CrE DTA) has been used to evaluate intestinal permeability in inflammatory bowe l disease, especially Crohn's disease. However, information about colonic p ermeability in ulcerative colitis (UC) is relatively scarce. The aim of thi s study was to investigate the urinary excretion of orally administered (51 )CrEDTA, its relation to disease activity and its response to medical thera py in patients with UC. Forty-three patients with UC and 19 controls were examined. Disease activit y was evaluated by endoscopy. In 19 patients with active UC, the (51)CrEDTA permeability test was repeated after medical therapy. (51)CrEDTA (95 mu Ci ; 26 MBq) was given orally after an overnight fast and urine was collected over a 24 h period. The first urine samples were taken 5 h and the second 2 4 h after the oral administration of (51)CrEDTA. Urine samples were counted in a gamma counter. In controls, the median 5 h and 24 h excretions were 0.10% and 0.93%, respe ctively. Patients with UC showed significantly increased urine (51)CrEDTA e xcretion at both time intervals (5 h: 2.41%, P<0.0002; 24 h: 6.72%, P<0.000 1). There was also a significant correlation between intestinal permeabilit y and disease activity (5 h: r=0.45, P=0.0025; 24 h: r=0.51 P=0.0006). Afte r medical therapy, (51)CrEDTA urinary excretion was significantly decreased (pre-treatment UC: 7.87%; post-treatment UC: 2.50%; P<0.0002). Briefly, th e (51)CrEDTA test reflected colonic permeability in UC and might be useful as an indicator of disease severity. Moreover, this study suggested that, i n patients with UC, medical therapy not only leads to the recovery of acute inflammation but also restores mucosal barrier integrity and function. ((C ) 2001 Lippincott Williams & Wilkins).