Comparison of different measurements of intestinal permeability in inflammatory bowel disease

We have compared different measurements of small intestinal permeability in 28 patients with Crohn's disease affecting the small intestine, 14 with ulcerative colitis and 17 controls. Patients and controls were given a drink containing 100 microCi (3.7 MBq) of 51Cr-ethylene diamine tetraacetic acid (51Cr-EDTA), 5 g lactulose, 5 g cellobiose, 1 g rhamnose, and 2 g mannitol. Urine was collected to 6 h after dosing, and then from 6 until 24 h. Recoveries of 51Cr-EDTA, lactulose, rhamnose, and mannitol were expressed as percentages of the amount administered. The only measurement that distinguished patients with Crohn's disease from both controls and patients with ulcerative colitis was the recovery of 51Cr-EDTA in the first 6 h after dosing. The mean recovery in patients with Crohn's disease was 1.07%; in controls, it was 0.35% (p = 0.013); in ulcerative colitis it was 0.39% (p = 0.032 compared to Crohn's; p = 0.492 compared to controls). No other measurement of permeability differentiated the three groups. Recoveries of 51Cr-EDTa and lactulose were highly correlated in each of the three groups. Recovery of rhamnose was significantly correlated with that of mannitol. In the patients with Crohn's disease, recovery of 51Cr-EDTA to 6 h was significantly correlated with some nonspecific laboratory indicators of inflammatory activity, namely, erythrocyte sedimentation rate, platelet count, white blood cell count, serum albumin, and C-reactive protein, but not with hemoglobin.