Last updated on:July 1st, 2022
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Neisseria, a gram-negative diplococcus, consists of two pathogenic species: N gonorrhoeae (gonococcus), which causes gonorrhea, and N meningitidis (meningococcus). Other non-pathogenic species exist. Humans are the only host for gonococcus.
Etiology and pathogenesis
N. gonorrhoeae colonizes the genital, rectal, and oral mucosa. These environmental niches allow for its survival, replication, and evasion of the human host immune system. Infections give rise to non-ulcerative lesions which are usually asymptomatic in female patients and symptomatic in male patients.
Systemic gonococcal infection may also develop. This occurs due to a combination of disruption of the vessel walls, immune-mediated vasculitis, disseminated intravascular necrosis (DIC), and micro-embolisms.
N. gonorrhoeae is an obligate human colonizer that cannot survive outside of its host. Infections spread with direct mucosal contact (genital-genital, rectal-genital, genital-rectal). Pharyngeal gonorrhea is acquired by receptive oral sex, fellatio being more efficient that cunnilingus at transmission. The pharynx may also act as a reservoir of infection, thus facilitating ongoing transmission between partners following oral sex. Neonates of infected mothers may acquire the infection when passing through the birth canal. Disseminated gonococcal infections (DGI) occur with hematogenous spread to other anatomic sites such as the skin, joints, liver, heart, or brain.
Persons at higher risk for gonorrhea include sexually active teenagers, sexually active adults with a new partner, individuals with multiple sexual partners, individuals who have sex without barrier contraception or with inconsistent condom use, and sex workers.