General STD Question

[Louis10]

Doc,  I posted this earlier on the patient to patient forum but think that it's probably more appropriate for you. Facts follow:
In monogamous relationship for 5+ years with girlfriend (both early 50’s), but approximately 8 weeks ago was given unprotected oral by 50 year old female.  Out of abundance of caution visited my Doc who said I had little or no risk, but prescribed Z-Pak at my request.  Took two pills the first day and one daily until completing the “pak”.  Resume sex with girlfriend (no sex with gf after other woman until Z-Pak completed)
Last week gf goes to doctor for routine physical and is told she his UTI and is prescribed Levaquin 250 for three days.  She never had symptoms and has never before had UTI.
Questions:
Is UTI coincidental to my sex with other woman?  Was Z-Pak effective in treating all potential STDs?  Including trich?  I read where standard dosing for STDs with Zithromax is 1g/2g in one dosing…Is the Z-Pak equally effective…I believe in total its less than 2g.  Thanks

[H. Hunter Handsfield, M.D.]

The UTI is just a coincidence.  UTIs in women often are associated with sex, but not because of sexual transmission of bacteria from the partner.  Instead, sex can 'massage' vaginal area bacteria into the urinary opening.  If E. coli or similar organisms are present, UTI can result.  If her provider diagnosed a typical UTI, there is no reason to suspect STD.  Azithromycin is not active against trichomonas, but you can't catch trich by oral sex, or chlamydia for that matter (the main STD for which azithromycin in prescribed).  However, the dose you received would effectively prevent the rare case of chlamydia or of nongonococcal urethritis (NGU), which can be caused by normal oral bacteria.

Bottom line:  There are no significant STD worries here.

Best wishes--  HHH, MD

[Louis10]

A quick follow-up, please.  Is it likely to pick up a trich infection from vaginal intercouse a year ago from a third party and pass it back and forth between my girlfriend without either of us having symptons for the entire year?  Could that account for her asymtomatic UTI?  Thanks.

[H. Hunter Handsfield, M.D.]

Trichomonas and UTI are not likely to be confused with one another, although it is possible.  Even without treatment, trich in men probably always clears up within a year.  Deal with the possibilty of trich if your provider diagnoses it in your partner.