Trichomoniasis Complications
Trichomoniasis causes significant reproductive and infectious complications, particularly in women, including increased HIV transmission risk, adverse pregnancy outcomes (preterm birth, premature rupture of membranes, low birthweight), and potential associations with pelvic inflammatory disease and cervical neoplasia. 1, 2
Major Complications in Women
Pregnancy-Related Complications
- Premature rupture of membranes, preterm delivery, and low birthweight are well-established complications requiring treatment of all symptomatic pregnant women 3, 1, 2
- Post-partum endometritis risk is increased in infected women 3
- Treatment after the first trimester with metronidazole 2g single dose is recommended to prevent these outcomes 4
HIV and STI Transmission
- Trichomoniasis significantly increases both HIV acquisition and transmission risk through persistent genital tract inflammation 1, 2, 5
- The infection facilitates transmission of other sexually transmitted infections beyond HIV 1
- This association has been demonstrated in multiple studies and represents a critical public health concern 6, 7
Reproductive Tract Complications
- Pelvic inflammatory disease can occur through local spread, though T. vaginalis does not cause systemic infection 1
- Cervicitis with persistent inflammation interferes with accurate cytological assessment, requiring repeat Pap smears 3 months after treatment 4
- Potential association with cervical neoplasia development has been identified 2, 7
- Atypical pelvic inflammatory disease and possible contribution to infertility have been reported 7
Complications in Men
Genitourinary Manifestations
- Approximately 80% of infected men are asymptomatic, making partner screening essential 1
- Symptomatic men develop urethritis (often presenting as nongonococcal urethritis), epididymitis, and prostatitis 1, 8, 7
- These remain localized infections without systemic spread 1
- Possible contribution to male factor infertility has been suggested 7
Treatment to Prevent Complications
Standard Therapy
- Metronidazole 2g orally as a single dose OR metronidazole 500mg twice daily for 7 days achieves approximately 95% cure rates 4, 9, 2
- The 7-day regimen is superior for HIV-uninfected women, reducing infection rates at 1-month test of cure compared to single-dose therapy 2
- Single-dose 2g metronidazole remains preferred for men 2
Partner Management
- Concurrent treatment of sexual partners is mandatory to prevent reinfection and reduce transmission 3, 4, 9
- Patients must abstain from sexual intercourse until both partners complete treatment and are asymptomatic 4, 9
- Failure to treat partners significantly increases reinfection risk 4
Treatment Failure Management
- If initial therapy fails, retreat with metronidazole 500mg twice daily for 7 days 4
- For repeated failure, use metronidazole 2g once daily for 3-5 days 4
- Persistent infections require specialist consultation and susceptibility testing, as drug resistance occurs in approximately 4-5% of cases 4, 2
- Tinidazole may be considered for metronidazole treatment failures 4, 10
Follow-Up and Screening
- Rescreening at 3 months after treatment is recommended due to high rates of repeat and persistent infections 2
- Follow-up is unnecessary for initially asymptomatic patients who become asymptomatic after treatment 3
Critical Pitfalls to Avoid
- Never use topical metronidazole gel for trichomoniasis—it has <50% efficacy and is not recommended 4
- Do not defer partner treatment, as this is the primary cause of reinfection 4
- Avoid missing treatment failures that may indicate drug resistance 4
- Do not overlook the need for repeat cytology after treatment, as inflammation can mask cervical abnormalities 4