[Epidemiologic and therapeutic study on gonococcal infections--clinical efficacy of norfloxacin].

We studied the basic and clinical effects of norfloxacin (NFLX) in 120 patients with gonococcal infections (110 men with urethritis and 10 women with cervicitis)--all residents at Sapporo City; and epidemiologically analyzed the sources of their infections. The male patients were between 16 and 67 years old and the female patients were between 20 and 61 years old, with a peak in the early 20s both for sexes. 70.6% of the male patients in their 10s were infected from their girl friends or so-called pick-up friends and 50% of the female patients from their husbands. The other half of the female were workers serving at so-called special massage parlors. The minimum inhibitory concentration (MIC) of NFLX against N. gonorrhoeae distributed was 0.0125 approximately 3.13 micrograms/ml, with a peak at 0.025 micrograms/ml. NFLX inhibited 93.3% of the clinical strains of this species at less than 0.1 microgram/ml and 96.2% at less than 1 microgram/ml, where the inoculation was 10(6) CFU/ml. Twenty one (20.2%) of the 104 N. gonorrhoeae strains were penicillinase-producing one (PPNG). NFLX inhibited 18 of these PPNG (85.7%) at less than 0.1 microgram/ml and the other 3 strains at 1.56 approximately 3.13 micrograms/ml. Oral administration of 200 mg NFLX showed the average peak serum level of 0.72 micrograms/microliter in 2 hours and the average peak level in the urethral secretions of 0.5 micrograms/ml in one hour. These two concentrations of NFLX covered 95.2% of the MIC distribution against N. gonorrhoeae. The clinical efficacy of 600 mg NFLX (peros) was 97.4 and 93.1% for a 3-and 7-day treatment for male urethritis; and 100% for both 3-and 7-day treatment for female cervicitis. Complicated urethritis with C. trachomatis was noticed in 32.7% of the male urethritis and in 20% of the female cervicitis cases. Urethral secretions among about half of these patients were observed even after treatment with NFLX. As a subsequent treatment, another effective chemotherapeutic is required against C. trachomatis. No adverse reactions were detected with NFLX. All the above results demonstrate that NFLX is a highly effective and safe chemotherapeutic agent for treatment of gonorrhoea.