Therapy of Crohn's disease with metronidazole -- an uncontrolled trial --.

Twelve patients with Crohn's disease (C.D.), in whom there was no improvement of symptoms and signs under protracted corticosteroid and salicylazosulphapyridine medication, were treated with 1 000 mg metronidazole (M.) daily. Crohn's Disease Activity Index (CDAI) was used as a criterion of therapeutic response. Seven patients showed improvement of symptoms with a concomitant fall of the CDAI from 300 +/- 84 to 56 +/- 32 (mean +/- SD) after 10 to 45 days. In one patient, therapeutic success was judged to be doubtful, a negative result being obtained in 4 patients. During follow-up, which was maximally 21 months, patients failed to relapse while receiving a maintenance dose of 250 and 500 mg of M. per day. -- Judicious attempts at drug withdrawal were undertaken during the first 6 months but were invariably followed by a relapse. -- Metronidazole given over a protracted period did not give rise to side-effects. -- A reduction of anaerobic bacterial invaders of the intestine is suggested to underlie the favourable therapeutic effect of M.