Vaginal trichomoniasis: Clinical sciences

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Introduction0:00–0:51

Vaginal trichomoniasis is among the most prevalent sexually transmitted infections, or STIs, worldwide. It is caused by the protozoan parasite, Trichomonas vaginalis.
Most patients infected with trichomonas have minimal or no symptoms, and untreated infections can last for months to years.
Trichomonas infection is associated with an increased risk of both HIV acquisition and HIV shedding, and it increases the risk of pelvic inflammatory disease among HIV-positive patients.
Additionally, it has been associated with an increased risk of cervical cancer. In pregnancy, trichomonas infection increases the risk of preterm birth, prelabor rupture of membranes and small for gestational age infants.Your first step in evaluating a patient who presents with a chief concern suggesting vaginal trichomoniasis is obtaining a focused history and physical exam.

Focused H&P0:51–2:41

This should include a sexual history, such as recent sexual activity or new partners, so be sure to have a private and confidential discussion.
Although it might be difficult, you should ask caregivers of young patients to step out of the room for this discussion.
Additionally, always consider sexual assault or abuse whenever a young patient has a positive sexual activity history, especially if the patient is a child.
If there is abuse going on, you will need to follow up with allegations of abuse in accordance with your State’s law. Now, keep in mind that trichomoniasis can be spread through vaginal fluids So some practices like sharing of sex toys can cause infection.
In addition to sexual history, ask about hygiene practices, such as douching, which can remove some of the bacteria that make up the normal vaginal flora, increasing the risk of overgrowth of infectious pathogens.
Although most patients are usually asymptomatic, some may report a malodorous vaginal discharge, vulvar pruritus or irritation, and dysuria.
Physical exam findings include a yellow frothy vaginal discharge; as well as vaginal or cervical erythema with petechiae, which is often referred to as a “strawberry cervix.” Based on these findings, you should suspect vaginal trichomoniasis.Here is a high-yield fact!
In the United States, the prevalence of vaginal trichomoniasis is almost 10 times higher among black patients than non-Hispanic white patients.
Some additional risk factors for trichomonas infection include socioeconomic factors like incarceration, having less than a high school education, and poverty.
So, if you suspect vaginal trichomoniasis, let’s take a look at your next step to confirm the diagnosis. To do this, obtain samples of the vaginal discharge from the vaginal walls and fornices.

Suspect vaginal trichomoniasis2:41–6:47

Evaluate the discharge with saline microscopy, particularly looking for motile trichomonads, and assess the vaginal pH. In addition, you may perform nucleic acid amplification testing, or NAAT, for Trichomonas vaginalis.
While NAAT testing is highly sensitive and detects more trichomonas infections, keep in mind that it’s more expensive and less timely than microscopy.
Okay, time for a couple of clinical pearls! First, vaginal cultures can be used to detect Trichomonas vaginalis, but these are rarely used, as NAAT testing has higher sensitivity and better detection rates.
Additionally, there are also some FDA-approved rapid tests available for detecting Trichomonas vaginalis. Second, vaginal trichomoniasis has a high prevalence in patients with HIV infection, can increase viral shedding, and is strongly associated with pelvic inflammatory disease among these patients.
For these reasons, yearly screening for trichomonas is recommended for patients with HIV infection. Now let’s review our results.
If there is an absence of trichomonads on saline microscopy, the vaginal pH is lower than or equal to 4.5, or a NAAT is negative for Trichomonas, consider an alternative diagnosis.
However, keep in mind that time matters here, and sensitivity decreases quickly within 1 hour after specimen collection, so you should attempt to evaluate it immediately!On the other hand, if saline microscopy reveals motile trichomonads and many polymorphonuclear white blood cells, the vaginal pH is greater than 4.5, or you have a positive NAAT for trichomonas, you can make the diagnosis of vaginal trichomoniasis.Now that we have our diagnosis, let's discuss treatment.
The first step in treatment is antibiotic therapy. Nitroimidazoles are the only medications that effectively treat trichomoniasis.
A 7-day regimen of oral metronidazole is the preferred treatment in biological females, while a single high-dose of oral metronidazole is recommended in biological males.
Alternatively, a single dose of oral tinidazole can be prescribed for both biological males and females. Keep in mind that tinidazole should be avoided in pregnancy, and breastfeeding should be deferred for 72 hours after a single dose.
On the other hand, metronidazole is safe to use in pregnancy. As you’re treating your patient, it is also important to think about their partner to avoid reinfection.
Consider expedited partner therapy, or EPT, in states where it is permissible by law. This involves treating sexual partners without requiring them to come in for an examination first.
In addition to antibiotic therapy, be sure to counsel patients to avoid douching and to abstain from intercourse until they, and all sexual partners, are treated and symptoms have resolved.
Another important thing to mention is that patients with one STI are at high risk for another. For that reason, you should screen all patients for HIV, gonorrhea, chlamydia, and syphilis.
Also, counsel patients to return if symptoms recur, and retest patients at 3 months due to high rates of reinfection.Let’s wrap this up with a clinical pearl!
An important thing to mention is that most recurrent infections are actually reinfections. Reinfection is treated with the same antibiotic regimen as an initial infection.
However, if there is no history of reexposure and you suspect a recurrent or persistent infection, treat with a higher multi-dose regimen of metronidazole or tinidazole.
If this is unsuccessful and you suspect ongoing persistent infection without reexposure, request a kit from the Centers for Disease Control and Prevention, or CDC, to perform drug resistance testing; and consider consultation with an infectious disease specialist.
Alright, as a quick recap… Vaginal trichomoniasis is a common STI caused by the protozoan parasite, Trichomonas vaginalis.

Review6:47–7:34

It is often asymptomatic, but some may report a malodorous vaginal discharge, vulvar pruritus or irritation, and dysuria.
Trichomoniasis in pregnancy is associated with poor outcomes, including prelabor rupture of membranes, preterm delivery, and small for gestational age infants.
The diagnosis of trichomoniasis can be made with office microscopy or NAAT testing. Treat trichomoniasis with oral nitroimidazoles, such as metronidazole or tinidazole, and counsel patients regarding abstinence, partner therapy, and the need for retesting.
Screen patients for other STIs, and remember the significant associations
Vaginal trichomoniasis: Video, Causes, Symptoms | Osmosis