Trichomoniasis: Affected Sites in Men and Women

Trichomonas vaginalis: Site-Specific Infection Patterns

Trichomoniasis is the most common non-viral STI globally (~156M cases/year). Site tropism differs by sex due to anatomy.

In Women

Site	Frequency	Clinical Features
Vagina	Primary (90%+)	Frothy yellow-green discharge, vulvar erythema, pruritus, dyspareunia
Cervix	Common	"Strawberry cervix" (colposcopic: punctate hemorrhages) — pathognomonic but only 2-5% visible
Urethra	Common	Dysuria, frequency (often mistaken for UTI)
Skene's/Bartholin's glands	Occasional	Reservoirs for recurrence
Endometrium/tubes	Rare	PID association; infertility link

In Men

Site	Frequency	Clinical Features
Urethra	Primary	Often asymptomatic; if symptomatic: urethritis (clear/mucopurulent discharge, dysuria)
Prostate	Common reservoir	Prostatitis; chronic bacterial prostatitis etiology
Epididymis	Rare	Epididymitis
Seminal vesicles	Rare	Seminal fluid contamination

Key Clinical Implications

• Asymptomatic carriage: 70-85% women, 90%+ men — drives transmission
• HIV synergy: 2-3x increased acquisition/transmission risk
• Pregnancy: Preterm birth, LBW, neonatal respiratory infection
• Diagnosis: NAAT (urine, vaginal swab) — gold standard; wet mount (50-60% sensitive)
• Treatment: Metronidazole 2g single dose (both partners); tinidazole alternative; avoid alcohol
• Resistance: 5-10% metronidazole resistance; susceptibility testing available

Screening Recommendations (CDC)

• HIV+ women: Annual
• High-prevalence settings: Consider
• Symptomatic: Test and treat
• Partners: Expedited partner therapy

Trichomonas is a "silent" STI with major reproductive health consequences. NAAT-based screening in high-risk groups is cost-effective.