URINARY-EXCRETION OF IOHEXOL AS A MARKER OF DISEASE-ACTIVITY IN PATIENTS WITH INFLAMMATORY BOWEL-DISEASE

Background: Increased intestinal permeability of water-soluble contras t medium during an intestinal follow-through is found in patients with active Crohn's disease in the small bowel. Methods: Urinary excretion of the water-soluble X-ray contrast medium iohexol was measured after oral administration in patients with inflammatory bowel disease and i n healthy controls. The patients were grouped on the basis of disease activity and location and extent of intestinal involvement. Results: U rinary excretion of iohexol was significantly higher in patients with active disease than in patients with quiescent disease or in healthy c ontrols (P = 0.005), and it correlated positively with activity indice s and with the extent of the disease. Conclusion: The intestinal perme ability of iohexol is significantly increased in patients with active inflammatory bowel disease in the small bowel and in the colon, wherea s the permeability of patients with inactive disease is similar to tha t in healthy controls. We suggest that urinary excretion of iohexol ca n be used as a marker of disease activity in patients with inflammator y bowel disease.