Efficacy of gentamicin and kanamycin in the treatment of uncomplicated gonococcal urethritis in Zambia.

As a result of the sudden increase in the incidence of penicillinase-producing Neisseria gonorrhoeae (PPNG) from 3.2% in 1980 to 25% in 1982 at a sexually transmitted disease clinic in Lusaka, Zambia, an open clinical trial comparing single-dose gentamicin (280 mg) and kanamycin (2 g) was performed; the drugs were administered intramuscularly to male patients with gonococcal urethritis. Gentamicin was given to 302 men, 220 of whom were followed for two weeks. Kanamycin was given to 113 men, 89 of whom were followed for the same interval. Cure rates of 98% and 95%, respectively, were obtained. Both drugs were well tolerated, with no adverse reactions. All isolates were screened for penicillinase production by the rapid iodometric method; the incidence of PPNG was 41.0%. In view of the high incidence of PPNG associated with failures of penicillin treatment, this drug is no longer useful in situations like that studied here. Since gentamicin and kanamycin have proved to be effective, they are now recommended for the treatment of gonococcal urethritis in Zambia.