In most cases of nonchlamydial NGU, no pathogen can be detected. M. genitalium, which appears to be sexually transmitted, is associated with both symptoms of urethritis and urethral inflammation and accounts for 15%–25% of NGU cases in the United States (240-243). T. vaginalis, HSV, and adenovirus also can cause NGU, but data supporting other Mycoplasma species and Ureaplasma as etiologic agents are inconsistent (244-247). Diagnostic and treatment procedures for these organisms are reserved for situations in which these infections are suspected (e.g., contact with trichomoniasis, genital lesions, or severe dysuria and meatitis, which might suggest genital herpes) or when NGU is not responsive to therapy. Enteric bacteria have been identified as an uncommon cause of NGU and might be associated with insertive anal intercourse