CULTURE FOR URETHRAL GONORRHEA FROM ASYMPTOMATIC MEN POSITIVE FOR NEISSERIA GONORRHOEAE BY URINE APTIMA COMBO 2 TESTING

Background In a previous study of men attending Melbourne Sexual Health Centre who had N. gonorrhoeae detected by urine Aptima Combo 2 (AC2) testing, 11% were asymptomatic, reporting no urethral symptoms. This study aimed to determine if N. gonorrhoeae can be cultured from asymptomatic men screening positive for N. gonorrhoeae by nucleic acid amplification testing (NAAT) of urine. Methods Between 1 July 2017 and 30 September 2018, men reporting sex with men attending Melbourne Sexual Health Centre who did not report urethral symptoms were screened for N. gonorrhoeae by AC2 testing of urine. NAAT positive men were recalled and a urethral swab performed for gonococcal culture using modified Thayer Martin media with determination of minimum inhibitory concentrations (MICs) for penicillin, azithromycin, ceftriaxone and ciprofloxacin by agar dilution. Results There were 612 cases (538 individuals) positive for N. gonorrhoeae by urine AC2: 548 (90%) reported urethral symptoms; 64 (10%) did not report symptoms. Thirteen asymptomatic cases were excluded because of antibiotic use at or following screening. Of the remaining 51 asymptomatic men, 25 (49%) had a urethral swab performed a median of 4 days after screening. Thirteen men had urethral discharge at the return visit, 7 of whom reported the discharge at the return visit. Of the 25 men who were swabbed, 18 (72%) were culture positive for N. gonorrhoeae. Among the 12 men who remained asymptomatic with no discharge at the return visit, 7 were culture positive. MIC profiles were obtained from all isolates. Conclusion Gonorrhoea was isolated in most asymptomatic men screening positive for N. gonorrhoeae by urine NAAT. Clinicians should consider culture in such men to ensure optimal surveillance for antimicrobial resistance. Isolation of N. gonorrhoeae in men without discharge indicates these are true infections with viable organisms. Disclosure No significant relationships.