Intestinal permeability in man: effects of acute systemic infections.

Intestinal permeability was assessed (within 24-48h of admission to hospital) in 7 patients suffering from acute infections, mainly pneumonia. The permeability test involved administering an oral solution containing a mixture of lactulose (10 g) mannitol (5 g and 0.5 microCi) and (51)Cr-EDTA (30 microCi), and collecting urine samples before, and between 0-6, 6-12 and 12-24 h after dosing. The excretion of the markers was compared with the results obtained from 24 normal or control subjects and 15 patients with coeliac disease. None of the markers were excreted in significantly different amounts in the infected patients compared to the control subjects. In contrast, the coeliac patients excreted (0-6 h) four-fold more lactulose, three-fold more (51)Cr-EDTA and two-fold less mannitol than the normal subjects. The ratio of lactulose: mannitol and (51)Cr-EDTA: mannitol were therefore six- to eight-fold greater in the coeliac patients than in the normal subjects. The results confirm the sensitivity of the test for detecting the presence of an enteropathy but provide no evidence of a change in intestinal permeability in systemic infections studied under the stated conditions.