Nongonococcal urethritis.

The nongonococcal urethritis (NGU) syndrome is a group of sexually transmitted infections that together exceed the frequency of gonorrhea in men in most urban areas of Europe and the United States, and probably in much of the remainder of the world. "Nongonococcal" is preferred to the term "non-specific" urethritis because the latter is less precise and carries the inaccurate implication that the causes are unknown and perhaps unknowable.