Antimicrobial resistance of Neisseria gonorrhoea in Bangkok: is single-drug treatment passé.

201 gonococcal isolates obtained from patients attending clinics in Bangkok were tested for in-vitro antimicrobial susceptibility. 42% of these isolates were penicillinase-producing Neisseria gonorrhoeae (PPNG); of the 116 isolates of non-PPNG 53% had a penicillin minimum inhibitory concentration (MIC) greater than or equal to 1 microgram/ml and the remainder had MIC greater than or equal to 0.06 microgram penicillin/ml. Similarly high in-vitro resistance was found for six of eight other antimicrobial agents tested. These high antimicrobial MICs reflect the difficulties encountered in selecting therapeutic agents for the control of gonorrhoea in Thailand. Single-drug treatment for gonorrhoea may no longer be effective in some settings. There is an urgent need to evaluate combination therapies appropriate to such settings.