Trichomoniasis

In women, symptoms of trichomoniasis range from none to copious, yellow-green, frothy vaginal discharge with a fishy odor, and soreness of the vulva and perineum, dyspareunia, and dysuria. Asymptomatic infection may become symptomatic at any time as the vulva and perineum become inflamed and edema develops in the labia. The vaginal walls and surface of the cervix may have punctate, red “strawberry” spots. Urethritis and possibly cystitis may also occur.

Men are usually asymptomatic; however, sometimes urethritis results in a discharge that may be transient, frothy, or purulent or that causes dysuria and frequency, usually early in the morning. Often, urethritis is mild and causes only minimal urethral irritation and occasional moisture at the urethral meatus, under the foreskin, or both. Epididymitis and prostatitis are rare complications.

• Vaginal testing with nucleic acid amplification tests (NAATs), wet-mount microscopic examination, rapid-antigen dipstick tests, or sometimes culture or cervical cytology

• Culture of urine or urethral swabs from men

Trichomoniasis should be suspected in women with vaginitis, in men with urethritis, and in their sex partners. Suspicion is high if symptoms persist after patients have been evaluated and treated for other infections such as gonorrhea and chlamydia infections.

In women, one of the following diagnostic tests of vaginal secretions may be done:

• NAAT

• Vaginal pH and wet mount microscopy

• Immunochromatographic flow dipstick test

NAATs are more sensitive than microscopic examination or culture for diagnosis of trichomoniasis in women. Immunochromatographic flow dipstick tests are also available for point of care testing in women. Cervical cytology (Pap test) is not used to test for trichomoniasis, but infection is sometimes detected incidentally.

Microscopic examination enables clinicians to evaluate for trichomoniasis and bacterial vaginosisbacterial vaginosis. The saline wet mount is examined microscopically as soon as possible to detect trichomonads, which can become immotile and more difficult to recognize within minutes after slide preparation. (Trichomonads are pear-shaped with flagella, often motile, and average 7 to 10 micrometers—about the size of white blood cells—but occasionally reach 25 micrometers.) If trichomoniasis is present, numerous neutrophils are also present. Trichomoniasis is also commonly diagnosed by seeing the organism when a Papanicolaou (Pap) test is done.

Culture of urine or urethral swabs is the only validated test for detecting T. vaginalis in men. In men, microscopy of urine is insensitive, and NAATs are not currently cleared by the FDA but could be available if local laboratories have done internal validation studies.

As with diagnosis of any STI, patients with trichomoniasis should be tested to exclude other common STIs such as gonorrhea and chlamydia.

• Treatment of sex partners

disulfiram

Sex partners should be seen and treated for trichomoniasis with the same regimens based on sex and should be screened for other STIs. If poor adherence to follow-up by sex partners is likely, treatment can be initiated in sex partners of patients with documented trichomoniasis without confirming the diagnosis in the partner.