para>Rare in prepubertal children; diagnosis should raise concern of sexual abuse. é á
Prevalence
- 3.1% of all U.S. women age 25 to 49 years; 1.5% of U.S. women age 15 to 24 years
- Racial disparity demonstrated
- 1.3% of white, non-Hispanic women
- 1.8% of Mexican American women
- 13.3% of black, non-Hispanic women (2)
ETIOLOGY AND PATHOPHYSIOLOGY
- Trichomonas vaginalis: a pear-shaped, flagellated, parasitic protozoan
- Grows best at 35 " ô37 é ░C in anaerobic conditions at pH of 5.5 to 6.0
- STI, but nonsexual transmission is possible because organism can survive several hours in moist environment.
Genetics
No known genetic considerations é á
RISK FACTORS
- Multiple sexual partners
- Unprotected intercourse
- Lower socioeconomic status
- Other STIs
- Untreated partner with previous infection
- Use of douching or feminine powders
GENERAL PREVENTION
- Use of male or female condoms
- Limiting numbers of sexual partners
- Male circumcision may be protective (3)[B].
COMMONLY ASSOCIATED CONDITIONS
- Other STIs, including HIV
- Bacterial vaginosis
DIAGNOSIS
HISTORY
- Women
- Yellow-green, malodorous vaginal discharge
- Vulvovaginal pruritus
- Dysuria
- 70 " ô85% are symptomatic.
- Men
- Dysuria
- Urethral discharge
- 80% are asymptomatic.
PHYSICAL EXAM
- Women
- Vaginal erythema
- Yellow-green, frothy, malodorous vaginal discharge
- Cervical petechiae (strawberry cervix; seen in ~10% of patients)
- Men: penile discharge, spontaneous and with expression
DIFFERENTIAL DIAGNOSIS
- Women (other vaginitides)
- Bacterial vaginosis
- Vaginal candidiasis
- Chlamydial infection
- Gonorrheal infection
- Men (other urethritides)
- Chlamydial infection
- Gonorrheal infection
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
- Wet mounts of vaginal or urethral discharge: direct visualization of motile trichomonads. Most common diagnostic method since inexpensive and available
- Sensitivity: 60 " ô70%; declines rapidly within 1 hour from collection
- Specificity: 99.8%
- Culture: sensitivity: >95%, specificity >99%; takes 4 to 7 days for growth
- Nucleic acid amplification test (NAAT)
- Gold standard for diagnosis (4)
- Sensitivity and specificity 95 " ô99%
- FDA approved for vaginal, endocervical, or female urine specimens
- Results in 1 hour
- Limited clinical availability
- Antigen detection
- ELISA and direct fluorescent antibody tests: sensitivity of 80 " ô90%
- Limited clinical availability
Follow-Up Tests & Special Considerations
Detection on cervical Papanicolaou smear é á
- Treat since highly specific (97 " ô99%)
- Not effective trichomonas screening test given sensitivity as low as 60%
Diagnostic Procedures/Other
Detection on self-obtained sample with DNA probe assay with specificity >98% é á
TREATMENT
- Symptomatic individuals require treatment.
- Sexual partners should be treated presumptively.
- Patients should abstain from sexual intercourse during treatment and until they are asymptomatic.
GENERAL MEASURES
The nitroimidazole class is only known effective antimicrobial treatment. If metronidazole resistance is suspected, use tinidazole (5)[A]. é á
MEDICATION
First Line
- Metronidazole: 2 g PO, 1 dose (6)[A]
- FDA pregnancy risk Category B
- Cure rate: 84 " ô98%
- Tinidazole: 2 g PO, 1 dose (6)[A]
- FDA pregnancy risk Category C
- Abstain from breastfeeding during treatment and for 3 days after the dose.
- More expensive
- Reaches higher levels in genitourinary tract
- Cure rate: 92 " ô100%
Second Line
- Metronidazole: 500 mg PO BID for 7 days
- Only if still symptomatic after initial treatment
- Considered first line in HIV-positive individuals
- Can dose with metronidazole or tinidazole 2 g daily for 7 days if infection persists
- May consider IV dosing of metronidazole based on case report that demonstrated cure after multiple failed oral regimens
Pregnancy Considerations
Metronidazole is effective for trichomoniasis infection during pregnancy but may increase the risk of preterm and low-birth-weight babies.
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ISSUES FOR REFERRAL
- Multidrug-resistant organism
- Patient allergy to metronidazole: Desensitization to metronidazole is recommended.
ADDITIONAL THERAPIES
- Limited clinical trials assessing effectiveness of alternative therapies (4)
- Intravaginal metronidazole gel is not effective.
- Suggested alternative therapies based on small number of case reports
- Paromomycin 6.25% cream
- Povidone-iodine douche
- Boric acid intravaginally
- Furazolidone intravaginally
COMPLEMENTARY & ALTERNATIVE MEDICINE
See "Additional Therapies. " Ł é á
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
- If symptoms persist after initial treatment, repeat wet mount or other testing.
- Retest women for T. vaginalis recommended within 3 months of treatment. Data insufficient for retesting men (6)[A]
- HIV-positive patients should be screened for trichomonas at time of HIV diagnosis and at least annually (6)[A].
DIET
Abstain from alcohol during treatment and for 24 hours following last dose of metronidazole or 48 to 72 hours following last dose of tinidazole due to disulfiram-like reaction. é á
PATIENT EDUCATION
Educate about the sexually transmitted aspect. é á
- Advise patient to notify sexual partner to be treated.
- Discuss STI prevention " öcondom use can prevent recurrence.
- Abstain from intercourse while undergoing treatment; use condoms if abstention is not feasible.
- Avoid alcohol during treatment with metronidazole or tinidazole.
PROGNOSIS
- Excellent
- Usually eliminated after one course of antibiotics
COMPLICATIONS
Pregnancy Considerations
Linked to low birth weight, preterm premature rupture of membranes, and preterm birth
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REFERENCES
11 World Health Organization. Prevalence and incidence of selected sexually transmitted infections, Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis and Trichomonas vaginalis. Methods and results used by WHO to generate 2005 estimates. World Health Organization Web site. http://www.who.int/reproductivehealth/publications/rtis/9789241502450/en/. Accessed December 10, 2015.22 Sutton é áM, Sternberg é áM, Koumans é áEH, et al. The prevalence of Trichomonas vaginalis infection among reproductive-age women in the United States, 2001-2004. Clin Infect Dis. 2007;45(10):1319 " ô1326.33 Sobngwi-Tambekou é áJ, Taljaard é áD, Nieuwoudt é áM, et al. Male circumcision and Neisseria gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis: observations after a randomised controlled trial for HIV prevention. Sex Transm Infect. 2009;85(2):116 " ô120.44 Muzny é áCA, Schwebke é áJR. The clinical spectrum of Trichomonas vaginalis infection and challenges to management. Sex Transm Infect. 2013;89(6):423 " ô425.55 Se â ▒a é áAC, Bachmann é áLH, Hobbs é áMM. Persistent and recurrent Trichomonas vaginalis infections: epidemiology, treatment and management considerations. Expert Rev Anti Infect Ther. 2014;12(6):673 " ô685.66 Workowski é áKA, Bolan é áGA. Sexually transmitted diseases treatment guidelines, 2015. MMWR Recomm Rep. 2015;64(RR-03):1 " ô137.
ADDITIONAL READING
- Allsworth é áJE, Ratner é áJA, Peipert é áJF. Trichomoniasis and other sexually transmitted infections: results from the 2001-2004 National Health and Nutrition Examination Surveys. Sex Transm Dis. 2009;36(12):738 " ô744.
- Fastring é áDR, Amedee é áA, Gatski é áM, et al. Co-occurrence of Trichomonas vaginalis and bacterial vaginosis and vaginal shedding of HIV-1 RNA. Sex Transm Dis. 2014;41(3):173 " ô179.
- Forna é áF, G â ╝lmezoglu é áAM. Interventions for treating trichomoniasis in women. Cochrane Database Syst Rev. 2003;(2):CD000218.
- G â ╝lmezoglu é áAM, Azhar é áM. Interventions for trichomoniasis in pregnancy. Cochrane Database Syst Rev. 2011;(5):CD000220.
- Hale é áT. Medications and Mothers ' Milk: A Manual of Lactational Pharmacology. 14th ed. Amarillo, TX: Hale Publishing; 2010.
- Hawkins é áI, Carne é áC, Sonnex é áC, et al. Successful treatment of refractory Trichomonas vaginalis infection using intravenous metronidazole. Int J STD AIDS. 2015;26(9):676 " ô678.
- Helms é áDJ, Mosure é áDJ, Secor é áWE, et al. Management of Trichomonas vaginalis in women with suspected metronidazole hypersensitivity. Am J Obstet Gynecol. 2008;198(4):370.e1 " ô370.e7.
- Kirkcaldy é áRD, Augostini é áP, Asbel é áLE, et al. Trichomonas vaginalis antimicrobial drug resistance in 6 US cities, STD Surveillance Network, 2009-2010. Emerg Infect Dis. 2012;18(6):939 " ô943.
- Klebanoff é áMA, Carey é áJC, Hauth é áJC, et al. Failure of metronidazole to prevent preterm delivery among pregnant women with asymptomatic Trichomonas vaginalis infection. N Engl J Med. 2001;345(7):487 " ô493.
- McClelland é áRS, Sangare é áL, Hassan é áWM, et al. Infection with Trichomonas vaginalis increases the risk of HIV-1 acquisition. J Infect Dis. 2007;195(5):698 " ô702.
- Meites é áE. Trichomoniasis: the "neglected " Ł sexually transmitted disease. Infect Dis Clin North Am. 2013;27(4):755 " ô764.
- Miller é áM, Liao é áY, Gomez é áAM, et al. Factors associated with the prevalence and incidence of Trichomonas vaginalis infection among African American women in New York City who use drugs. J Infect Dis. 2008;197(4):503 " ô509.
- Saperstein é áAK, Firnhaber é áGC. Clinical inquiries. Should you test or treat partners of patients with gonorrhea, chlamydia, or trichomoniasis? J Fam Pract. 2010;59(1):46 " ô48.
- Satterwhite é áCL, Torrone é áE, Meites é áE, et al. Sexually transmitted infections among US women and men: prevalence and incidence estimates, 2008. Sex Transm Dis. 2013;40(3):187 " ô193.
- Silver é áBJ, Guy é áRJ, Kaldor é áJM, et al. Trichomonas vaginalis as a cause of perinatal morbidity: a systematic review and meta-analysis. Sex Transm Dis. 2014;41(6):369 " ô376.
- Wendel é áKA, Workowski é áKA. Trichomoniasis: challenges to appropriate management. Clin Infect Dis. 2007;44(Suppl 3):S123 " ôS129.
- Wiese é áW, Patel é áSR, Patel é áSC, et al. A meta-analysis of the Papanicolaou smear and wet mount for the diagnosis of vaginal trichomoniasis. Am J Med. 2000;108(4):301 " ô308.
CODES
ICD10
- A59.9 Trichomoniasis, unspecified
- A59.03 Trichomonal cystitis and urethritis
- A59.01 Trichomonal vulvovaginitis
- A59.09 Other urogenital trichomoniasis
- A59.8 Trichomoniasis of other sites
- A59.02 Trichomonal prostatitis
ICD9
- 131.9 Trichomoniasis, unspecified
- 131.02 Trichomonal urethritis
- 131.01 Trichomonal vulvovaginitis
- 131.00 Urogenital trichomoniasis, unspecified
- 131.03 Trichomonal prostatitis
- 131.09 Other urogenital trichomoniasis
- 131.8 Trichomoniasis of other specified sites
SNOMED
- 56335008 Infection by Trichomonas (disorder)
- 30116001 Trichomonal urethritis
- 81598001 Trichomonal vulvovaginitis (disorder)
- 35089004 Urogenital infection by Trichomonas vaginalis (disorder)
- 71590000 Trichomonal prostatitis
CLINICAL PEARLS
- Both partners need to be treated for trichomoniasis.
- Retest women within 3 months of treatment.
- Avoid alcohol during treatment with standard agents.
- Treatment does not reduce risk of adverse pregnancy outcomes.
- Male circumcision may be protective.
- Annual screening recommended for HIV-positive patients.
- Not a nationally notifiable condition