Testing for Trichomonas in Males
Yes, there are multiple ways to test for Trichomonas vaginalis in men, with nucleic acid amplification tests (NAATs) being the most sensitive option, though they are not FDA-approved for male specimens—laboratories that have validated their performance under CLIA requirements can perform these tests. 1
Recommended Testing Methods
First-Line: Nucleic Acid Amplification Tests (NAATs)
- NAATs demonstrate superior sensitivity for trichomonas diagnosis in men compared to all other methods 1, 2
- The T. vaginalis NAAT (APTIMA) is FDA-licensed only for female specimens (cervical/vaginal swab, urine, PreservCyt Solution), but laboratories that have met CLIA and other regulatory requirements and validated their T. vaginalis NAAT performance on male specimens may perform this test 1
- Specimen types for men include:
Alternative Testing Methods (Lower Sensitivity)
Culture Methods:
- Culture in Diamond media or other trichomoniasis-specific culture systems (e.g., InPouch) 1
- Sensitivity approximately 70% compared to NAAT methods 2
- Can be performed on urethral exudates and urine 4
- Important caveat: Culture was readily demonstrated from urethral secretions but less reliably from centrifuged urine deposits in some studies 4
Microscopy:
- Direct microscopic examination of urethral secretions or centrifuged urine 1, 4
- Major limitation: sensitivity only 60-70%, leading to frequent false-negative results 1, 2
- Requires immediate viewing for optimal results 1
Urine Cytology:
- Can detect Trichomonas organisms (round to oval, with eccentric nuclei and cytoplasmic granules) 5
- May represent the initial diagnostic test in some men, particularly those undergoing evaluation for hematuria or other urinary symptoms 5
- Incidence in male urine cytology specimens is approximately 0.1% 5
Clinical Context for Testing
High Prevalence in Male Partners
- 71.7% of male partners of women with trichomoniasis are infected 3
- 77.3% of infected male partners are asymptomatic 3
- Approximately 80% of all male infections are asymptomatic, creating a substantial reservoir for ongoing transmission 1, 2
When Symptomatic, Men Present With:
- Urethral discharge (most commonly milky white and fluid) 4
- Urethral irritation 4
- Symptoms often present for >4 weeks (78% of cases) 4
- Can cause urethritis, epididymitis, and prostatitis 1, 2
- Lower urinary tract symptoms, most commonly hematuria 5
Risk Factors
- Male partners of infected women 3
- Younger age (20-39 years) 3
- Less consistent condom use 2
- Racial disparities: prevalence rates 10 times higher among non-Hispanic African Americans 1, 2
Critical Testing Pitfalls
The major pitfall is relying on wet mount microscopy alone, which misses 30-40% of infections due to poor sensitivity 1, 2. This leads to underrecognition and undertreatment of a highly prevalent STI that affects an estimated 3.7 million Americans 6.
Another common error is assuming NAATs cannot be used for male specimens—while not FDA-cleared, validated laboratory-developed tests are permissible and should be utilized given their superior performance 1.
Partner Testing Considerations
- High rates of concordant infection (71.7%) suggest all male partners of infected women should be tested and treated 3
- Vaginal pH >4.5 in the female partner is independently associated with infection in the male partner 3
- Concomitant treatment of sexual partners is recommended to prevent reinfection 1, 7