What is nongonococcal urethritis (NGU)?
NGU refers to an infection of the urethra (the tube running from the bladder through the penis in men or the labia in women through which urine passes) caused by some agent other than gonorrhea. This infection can be caused by any of several different organisms although the most frequent cause of NGU is a germ called chlamydia, and is a sexually transmitted disease (STD).