Trichomonal Vaginitis

Aka: Trichomonal Vaginitis, Trichomonas, Trichomoniasis

1. See also
   1. Vaginitis
   2. Sexually Transmitted Infection
   3. Non-Gonococcal Urethritis
2. Epidemiology
   1. Accounts for 10% of Vaginitis
   2. Prevalence
      1. General gynecology clinics: 13-23%
      2. Prostitutes: 75%
      3. Increasing Prevalence in asymptomatic women over age 45 years old
      4. More common in women with HIV Infection
         1. Screen women with HIV yearly
   3. Transmission
      1. Sexually Transmitted Disease
         1. Trichomonas is the most common non-viral Sexually Transmitted Infection
      2. Men are asymptomatic in 90% of cases
      3. Often transmitted with Gonorrhea and Chlamydia
      4. Rarely transmitted by moist cloths
3. Etiology
   1. Protozoan infection
4. Risk Factors
   1. Multiple sexual partners
   2. Sexually Transmitted Infections
   3. Unprotected Intercourse
   4. Illicit Drug use
   5. Tobacco Abuse
5. Symptoms
   1. Asymptomatic in 25-44% of women
   2. Copious, yellow-green or grayish-green Vaginal Discharge (variably present)
      1. Fishy odor to discharge (variably present)
      2. Frothy discharge (Carbon dioxide bubbles)
         1. Sensitivity: 10%
         2. Specificity: 70%
   3. Vulvar and vaginal Pruritus with irritation and edema
   4. Dysuria (20%)
6. Signs
   1. Vulvar edema and erythema
   2. Tender vaginal or vulvar ulcerations
   3. Strawberry Cervix (2-3% of cases)
      1. Punctate Hemorrhages or Petechiae
      2. Telangiectasia
7. Lab
   1. Vaginal pH > 5.0
   2. KOH Preparation
      1. Sniff Test positive
         1. Fishy odor to discharge when KOH added (often negative)
   3. Wet Preparation (from vaginal vault, not endocervix)
      1. Read slide immediately
         1. Motility wanes quickly, over minutes
         2. Trichomonad shape morphs from pear-shaped to round with slide drying
      2. Motile pear shaped Trichomonads with flagella exiting from tapering end (70%)
         1. Twice the size of White Blood Cells (WBC)
         2. 
      3. Efficacy
         1. Test Sensitivity: 60-70%
   4. Specific diagnostic tests
      1. DNA Testing is preferred for Trichomonas diagnosis, and can be added to DNA probe and liquid pap
         1. Preferred over microscopy in symptomatic or high risk women
         2. Nucleic Acid Amplification Test (NAAT) Sensitivity: >95%
            1. May be added to GC/Ch DNA probe or liquid pap
         3. Rapid swabs are also available, with Test Sensitivity 80-90%
            1. Available as point-of-care clinic based tests
            2. Test Sensitivity: 83%
            3. Test Specificity: >97% (False Positives are a concern in regions of low Prevalence)
      2. BD Affirm VPIII Microbial Identification Test (Nucleic Acid probe)
      3. Osom Trichomonas Rapid Test (immunochromatographic)
   5. Other testing
      1. Gram Stain
         1. White Blood Cells over 10 per high powered field
      2. Culture of Trichomonas vaginalis (replaced with DNA probes)
         1. Grown on modified Diamond media
8. Associated Conditions
   1. Preterm Labor
   2. Test for other Sexually Transmitted Disease
      1. NeisseriaGonorrhea
      2. Chlamydia trachomatis
9. Management
   1. General
      1. Treat Sexual Partner also
         1. Metronidazole 500 mg orally twice daily for 7 days is most effective for male partners
         2. However, Metronidazole 2 g orally for one dose is recommended in guideline for male partners
         3. Abstain from intercourse until they and their sexual partners are treated
      2. Avoid treatment in first trimester of pregnancy
      3. Avoid intravaginal preparations of Metronidazole or Tinidazole due to low cure rates
      4. Re-test in 3 months (high risk of reinfection)
   2. Non-Pregnant, Non-Lactating Patient
      1. Metronidazole (Flagyl) 500 mg orally twice daily for 7 days (preferred) OR
         1. Avoid single Metronidazole (Flagyl) 2 g oral dose (less effective)
      2. Tinidazole (Tindamax) 2 grams orally for 1 dose
         1. Teratogenic, Category D (do not use if any risk of pregnancy)
         2. More expensive than Metronidazole options
   3. Pregnant (after first trimester, and preferred after 37 weeks)
      1. Metronidazole (Flagyl) 2 g orally for 1 dose OR
      2. Metronidazole (Flagyl) 500 mg orally twice daily for 7 days
   4. Lactation
      1. Metronidazole (Flagyl) 2 grams orally for 1 dose
      2. Discontinue Lactation for 24 hours after dose
   5. Persistent or Recurrent Cases
      1. Retreat both the sexual partner and the patient
      2. Metronidazole 500 mg orally twice daily for 7-14 days
      3. Metronidazole 2g orally daily for 3 days (for up to 7 days)
      4. Metronidazole gel 5g PV bid for 5 days
      5. Povidone-Iodine Suppository PV bid for 14 days
      6. Clotrimazole 100 mg vag tab PV qhs for 7 days
      7. Tinidazole 2 g orally daily for 5 days
         1. Teratogenic, Category D (do not use if any risk of pregnancy)
      8. Paromomycin (Humatin) 5g intravaginally qd x14 days
         1. Higher rate of Vulvitis and local ulceration
      9. Secnidazole (Solosec) 2 g orally for 1 dose
         1. Expensive in 2021 ($270 for one dose)
         2. (2021) Presc Lett 28(9): 49-50
10. Complications
    1. HIV Infection and transmission risk
    2. Preterm Labor
    3. Associated with concurrent other Sexually Transmitted Infections
11. References
    1. Mandell (2000) Infectious Disease, Churchill, p. 2894-7
    2. (1998) MMWR Morb Mortal Wkly Rep 47:1-115 [PubMed]
    3. Epling (2001) Am Fam Physician 64(7):1241-4 [PubMed]
    4. Workowski (2006) MMWR Recomm Rep 55:1-94 [PubMed]