[Acute urethritis caused by Neisseria meningitidis and Chlamydia trachomatis].

A 16-year-old heterosexual man presented to our hospital with a purulent urethral discharge and pain at voiding. These symptoms began seven days after oral-genital contact (fellatio) with his partner. A Gram-stained smear from the urethral discharge showed Gram-negative diplococci, and the antigen of Chlamydia trachomatis from urine was positive. We initially made a diagnosis of urethritis caused by Neisseria gonorrhoeae and C. trachomatis. However, N. meningitidis was isolated by culture. Clinicians should pay attention to the possibility of N. meningitidis infection in all cases resembling gonococcal urethritis.