Infectious Disease Compendium

Trichomonas vaginalis


A protozoa.

Epidemiologic Risks

Spread sexually, one the few STD's that may be spread non sexually, (:still, if you got it from a toilet seat, that has to be an uncomfortable place to have sex.:).


Up to half can be asymptomatic, it usually causes vaginitis discharge and irritation; men, when symptomatic, get urethritis.70% of male partners will have the infection, 77% of whom will be asymptomatic (PubMed).Increases the spread of HIV (PubMed).


A single dose 2 gm of metronidazole or 500 mg po bid x 7 d.


Resistance to metronidazole increasing is increasing (PubMed), treatment is problematic. Topical rx will fail. Treat the partner to prevent relapse. What to do with a trich knee is uncertain.

ICD9 Codes (Soon to be supplanted by ICD10)

Trichomoniasis 131.9; bladder 131.09; cervix 131.09; intestinal 007.3; prostate 131.03; seminal vesicle 131.09; urethra 131.02; urogenitalis 131.00; vagina 131.01; vulva 131.01; vulvovaginal 131.01.