Neisseria gonorrhoeae RNA/DNA hybridization and culture for screening of gonococcal infections in a low-prevalence population.

Gonorrhea is still a major sexually transmitted disease (STD) worldwide. Its etiologic diagnosis is based on identification of the causative agent, Neisseria gonorrhoeae, by culture of genital secretions, which is often hampered by difficulties of sample collection and transport. Alternatively, nucleic acid hybridization techniques for routine diagnosis of N. gonorrhoeae appear to be useful by eliminating problems associated with bacterial viability, particularly for surveillance of low-prevalence populations. Our study among 1,508 outpatients undergoing routine examination for common STDs used RNA/DNA hybridization with a DNA probe specific for N. gonorrhoeae (Gen Probe Pace 2) and classical culture. Of the 1,750 specimens tested, 12 were positive by DNA probe and culture. In 8 cases, only DNA probe was positive while culture was negative. In 3 of these discrepant cases clinical and epidemiological data suggested true N. gonorrhoeae infection. Thus, DNA probe assay for N. gonorrhoeae may greatly improve screening of N. gonorrhoeae among low-prevalence populations. However, culture remains mandatory for testing antimicrobial resistance of these highly communicable infectious agents.