EFFECTIVENESS OF NORFLOXACIN AND OFLOXACIN FOR TREATMENT OF GONORRHEAAND DECREASE OF INVITRO SUSCEPTIBILITY TO QUINOLONES OVER TIME IN RWANDA

Objective-To study the effectiveness of single-dose norfloxacin and of loxacin in the treatment of gonococcal urethritis in men, and to monit or in vitro antimicrobial susceptibility to these antibiotics over tim e. Setting-Centre Medico-Social de Bilyogo, Kigali, Rwanda. The only c linic in Rwanda using quinolones for the treatment of gonorrhoea. Meth od-As part of a monitoring programme, men with gonococcal urethritis w ere evaluated after treatment with norfloxacin (800 mg) in 1986 and 19 87, and after treatment with ofloxacin (400 mg) in 1989. Results-Neiss eria gonorrhoeae was eradicated from the urethra from 96.0% (189/197) and from 97.1% (166/171) men treated with norfloxacin and ofloxacin, r espectively. Overall 38.2% of the pretreatment isolates produced penic illinase (PPNG isolates) and 20.4% (44/216) of the tested non-PPNG iso lates were chromosomally resistant to penicillin (MIC greater-than-or- equal-to 2.0 mg/l). Resistance to tetracycline and thiamphenicol was c ommon in both PPNG and non-PPNG and increased considerably in 1989. Al l isolates were susceptible to kanamycin, spectinomycin, ceftiaxone, n orfloxacin, ofloxacin and ciprofloxacin. However, a higher number of i solates recovered in 1989 showed decreased susceptibility to the quino lones. Treatment failure occurred more often in subjects with isolates having MIC values greater-than-or-equal-to 0.06 mg/L of norfloxacin ( p = 0.006). Seven out of 13 patients who did not respond to therapy ha d no signs nor symptoms of urethritis. Conclusion-Quinolone antibiotic s are now indicated as a first line treatment of gonorrhoea in countri es with a problem of antimicrobial multiresistance. However, antimicro bial susceptibility to the quinolones may decrease rapidly, and close monitoring of the in vitro susceptibility of N gonorrhoeae and the cli nical effectiveness of the antibiotics is imperative.