Sensitivity of microscopy for the rapid diagnosis of gonorrhoea in men and women and the role of gonorrhoea serovars

Auditing the sensitivity of microscopic diagnosis of gonorrhoea is recommended by the current guidelines. A retrospective study was performed of 596 cases of positive cultures for Neisseria gonorrhoeae in modified New York City culture (MNYC) media diagnosed from 1995 to 1999. The sensitivity of the cervical slides in women was 51% while in men who have sex with men (MSM) the sensitivity of urethral and rectal slides were 89% and 54% respectively. The sensitivity of urethral slides in heterosexual men was 84%. Neisseria serovar 1B02 among MSM and serovar 1B31 among women were mostly undiagnosed with microscopy. Serovars 1A05, 1A21, B08 among heterosexual men were exclusively associated with negative microscopy. Microscopy is important in the rapid detection and treatment of gonorrhoea. Infections with certain serovars are less likely to be detected by microscopy; making them more likely to spread within the community. Culture from different ano-genital sites is essential to maximize detection of gonorrhoea in all patients.