METRONIDAZOLE REDUCES INTESTINAL INFLAMMATION AND BLOOD-LOSS IN NONSTEROIDAL ANTIINFLAMMATORY DRUG-INDUCED ENTEROPATHY

This study assessed the effect of metronidazole on the gastroduodenal mucosa, intestinal permeability, blood loss, and inflammation in patients on non-steroidal anti-inflammatory drugs (NSAIDs). Thirteen patients were studied before and after 2-12 weeks' treatment with metronidazole 800 mg/day, while maintaining an unchanged NSAID intake. Intestinal inflammation, as assessed by the faecal excretion of indium-111 labelled neutrophils, and blood loss, assessed with chromium-51 labelled red cells, were significantly reduced after treatment (mean (SD) In-111 excretion 4.7 (4.7)% v 1.5 (1.3)% (N<1.0%), p<0.001, Cr-51 red cells loss 2.6 (1.6) ml/day v 0.9 (0.5) ml/day (N<1.0 ml/day), p<0.01). Intestinal permeability assessed as the 5 hour urinary excretion ratio of Cr-51EDTA/L-rhamnose did not change significantly (0.133 (0.046) v 0.154 (0.064), p>0.1) and there were no significant changes in the endoscopic or microscopic appearances of the gastroduodenal mucosa. These results suggest that the neutrophil is the main damaging effector cell in NSAID induced enteropathy. The main neutrophil chemoattractant in this enteropathy may be a metronidazole sensitive microbe.