Gonococcus

Gonococcus refers to Neisseria gonorrhoeae, a Gram-negative diplococcus and the bacterial cause of gonorrhea, a sexually transmitted infection. It is a member of the genus Neisseria, with humans as the natural host.

Transmission occurs primarily through sexual contact and can be passed from an infected person to a partner during vaginal, anal, or oral sex. Newborns may acquire infection from an infected birth canal during delivery.

Clinical presentation varies by sex and site. In men, infection commonly causes urethritis with purulent discharge and dysuria. In women, cervicitis often develops and may be asymptomatic; if untreated, it can lead to pelvic inflammatory disease and infertility. The bacteria can disseminate and cause arthritis, dermatitis, and, rarely, endocarditis or meningitis.

Diagnosis relies on nucleic acid amplification tests from genital, rectal, or pharyngeal specimens. Gram stain can support diagnosis in symptomatic men. Culture on selective media such as Thayer-Martin remains important for antimicrobial susceptibility testing and outbreak investigations.

Treatment is challenged by antimicrobial resistance. Penicillin, tetracycline, and fluoroquinolone resistance is common; current guidelines favor cephalosporin therapy, typically ceftriaxone, with consideration of additional coverage for Chlamydia with azithromycin or doxycycline. Partner notification and treatment are essential.

Prevention focuses on safe sex practices, routine screening of high-risk groups, prompt diagnosis and treatment of cases, and vaccination research. Gonorrhea remains a globally important sexually transmitted infection with ongoing concerns about resistance.