NGU

I slept with a guy two weeks ago and he began experiencing symptoms of NGU within a couple of days.  He tested negative for chlamydia and gonorrhea.  He was diagnosed with NGU but the nurse was unsure of the cause.  I also tested negative for all STD's before we slept together.  He had protected sex with another person (female) a couple of weeks before.  

What is the possibility that he got this from me?  If we're both negative for STD's, what caused it?  I plan to see my doctor b/c of this so what tests do I need to request?

[H. Hunter Handsfield, M.D.]

Nongonococcal urethritis (NGU) is caused by chlamydia about one third of the time.  The causes in the other two thirds generally aren't known.  Other cases of NGU probably result from oral sex, where bacteria that are entirely normal in the mouth cause inflammation in the urethra.  But in most cases all the standard tests for STD in fact will be negative, as with you. Some of the apparent causes of nonchlamydial NGU probably are part of the normal vaginal bacteria in some women. Some are caused by a newly discovered bacteria called Mycoplasma genitalium, others by an older one called Ureaplasma urealyticum.

Yes, your partner probably caught the infection from you.  However, it may not mean much for your health.  No research has ever shown any important health consequence in women who are the partners of men with nonchlamydial NGU--no tubal infection, no infertility, nothing.  So the risk to your health is small.

Having said all that, most STD specialists would recommend you be treated with doxycycline or azithromycin.  (The odds are good your partner was given one of those antibiotics.)  Chlamydia tests can be falsely negative; and even if there is no serious health threat to you, treatment may help prevent your reinfecting your partner or future partners.

Sorry that it's such a confusing situation.  Best wishes--  HHH, MD