Urethritis is inflammation of the urethra typically caused by infectious organisms including Chlamydia trachomatis or Neisseria gonorrhoeae. In some cases, urethritis may result from noninfectious conditions or may be idiopathic.

Patients have urethral discharge, which, depending on the etiology of the urethritis, can vary in amount and appearance. In some cases, the discharge may be scant and clear. Gonococcal urethritis typically causes frankly purulent discharge. Patients may also have dysuria or urethral pruritus. In some cases, urethritis may be accompanied by epididymitis (usually unilateral epididymal pain), proctitis (depending on exposure), and/or fever.

Multiple pathogens cause urethritis, including N gonorrhoeae, C trachomatis, Mycoplasma genitalium, and Trichomonas vaginalis. Less common pathogens include Neisseria meningitidis, Neisseria elongata, Ureaplasma spp, Haemophilus influenzae, Haemophilus parainfluenzae, Corynebacterium spp, Kurthia gibsonii, Aerococcus urinae, Epstein-Barr virus, Ureaplasma spp, adenovirus, and herpes simplex virus. In addition, patients should be tested for other sexually transmitted diseases, including HIV, since co-infection is possible (especially in high-risk patient populations).