Single-dose treatment of male patients with gonococcal urethritis using 2g spectinomycin: microbiological and clinical evaluations

The microbiological and clinical efficacies of a single-dose treatment of 2g spectinomycin administered by intramuscular injection were studied in 365 male patients with gonococcal urethritis. A total of 210 patients (57.5%) could be evaluated, in 28 (13.3%) of whom Chlamydia trachomatis was detected in addition to Neisseria gonorrhoeae. A single dose of spectinomycin eradicated N. gonorrhoeae in 203 (96.7%) of the 210 patients. Among patients in whom N. gonorrhoeae was eradicated, pyuria and clinical symptoms, respectively, disappeared in 92.6% (162/175) and 98.9% (173/175) of patients without concomitant C. trachomatis and in 78.6% (22/28) and 71.4% (20/28) with C. trachomatis. Minimal inhibitory concentrations (MICs) were determined for four of seven N. gonorrhoeae strains isolated after spectinomycin treatment. MICs to spectinomycin for three of the four isolates were 16 microg/mL (defined as susceptible) and the MIC of the other isolate was 128 microg/mL, indicating resistance. The resistant isolate was a multidrug-resistant strain with resistance to ciprofloxacin, tetracycline, penicillin and cephalosporins, except for ceftriaxone. The results of this study indicate that a single-dose treatment using 2g spectinomycin is effective in treating patients with urethritis caused by N. gonorrhoeae, even in the era of multidrug-resistant N. gonorrhoeae.