Treatment of chancroid by clavulanic acid with amoxycillin in patients with beta-lactamase-positive Haemophilus ducreyi infection

Abstract

Multiresistant strains of Haemophilus ducreyi, the aetiological agent of chancroid, are prevalent in Nairobi, Kenya, where tetracyclines and sulphonamides are no longer very effective in the treatment of chancroid. The following regimens (given three times daily for seven days) were compared in a double-blind randomised trial--amoxycillin 500 mg, amoxycillin 500 mg and clavulanic acid 125 mg, and amoxycillin 500 mg and clavulanic acid 250 mg. 68 of 100 ulcers were culture-positive for H. ducreyi. All strains of H. ducreyi produced beta-lactamase. At day 7 none of the amoxycillin-treated patients had responded clinically or bacteriologically, whereas all but 2 of 56 patients treated with an amoxycillin/clavulanic-acid regimen had responded clinically and H. ducreyi had been eradicated from their ulcers. The combination of amoxycillin-clavulanic acid appears to be very effective for the treatment of chancroid. The results of this study accord with H. ducreyi as the primary pathogen of chancroid.