INTESTINAL PERMEABILITY AND THE PREDICTION OF RELAPSE IN CROHNS-DISEASE

To see whether intestinal permeability (IP) predicted relapse in Crohn 's disease, we measured IP in 72 patients with quiescent Crohn's disea se using the lactulose-mannitol test. The permeability index (lactulos e/mannitol) was significantly higher in patients than in controls (0.0 46 [SEM 0.005] vs 0.018 [SEM 0.002], respectively). Patients were foll owed for 1 year after the test. 26 of the 37 patients with raised perm eability, but only 6 of the 35 with normal permeability relapsed withi n 1 year after the test (p<0.001). The sensitivity of the permeability test as a predictor for relapse was 81%. A significant correlation wa s found between the value of the permeability index and the probabilit y of relapse (p<0.01). These results show that increases in intestinal permeability precede clinical relapses in Crohn's disease and so are an indicator of subclinical disease. The measurement of intestinal per meability may lead to a better understanding of the pathogenesis of Cr ohn's disease.