Anogenital infection with Neisseria meningitidis in homosexual men.

Among monosexual men anal infection with Neisseria meningitidis was more prevalent (15 of 731 men) than expected and significantly more prevalent than urethral infection with N. meningitidis (three of 669 men, P less than 0.01). Anal infection was also significantly more prevalent among homosexual men than among heterosexual women (two of 1,197 women, P less than 0.001). These differences in rates of prevalence may be best explained by a preference of meningococci for anal mucosa and by the common homosexual practice of oral-anal sexual contact. Serogrouping of the 17 anal and three urethral isolates revealed a broad representation of serogroups often found in meningococcal pharyngeal carriage in the community. Of 14 patients who returned for a test-of-cure culture within seven days of treatment with an antibiotic regimen recommended for anogenital gonococcal infection, each was culture-negative for N. meningitidis. Minor and symptoms in three men and profuse urethral discharges in two men resolved with treatment.