eMedicine Specialties > Emergency Medicine > Infectious Diseases

Trichomoniasis

R Gentry Wilkerson, MD, Clinical Assistant Professor, Department of Emergency Medicine, State University of New York-Downstate; Attending Physician, Department of Emergency Medicine, Kings County Hospital
Richard H Sinert, DO, Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center; Benjamin W Friedman, MD, Staff Physician, Department of Emergency Medicine, Jacobi/Montefiore Medical Centers; Judith C Brillman, MD, Professor, Department of Emergency Medicine, Assistant Dean, Graduate Medical Education, University of New Mexico School of Medicine

Updated: Oct 22, 2009

Introduction

Background

Trichomoniasis is a nonreportable sexually transmitted disease (STD) caused by the parasite Trichomonas vaginalis. Humans are the only known host with the trophozoite transmitted via coitus. Transmission via fomites has been reported. The organisms are usually pyriform in shape, although they may take an amoeboid shape after attachment to the vaginal epithelium.

Life cycle of Trichomonas vaginalis.T vaginalis resides in the female lower genital tract and the male urethra and prostate (1), where it replicates by binary fission (2). The parasite does not appear to have a cyst form and does not survive well in the external environment. T vaginalis is transmitted among humans, its only known host, primarily by sexual intercourse (3). Image courtesy of the Centers for Disease Control and Prevention.

Trichomonas vaginalis on a saline wet mount at 40X on the microscope. Several motile parasites transit through the field, surrounded by white blood cells and squamous epithelial cells.

Video available at http://img.medscape.com/pi/emed/ckb/emergency_medicine/756148-780913-787722-1769101.flv.

Trichomonas vaginalis. A, Two trophozoites of T vaginalis obtained from in vitro culture, stained with Giemsa. B, Trophozoite of T vaginalis in a vaginal smear, stained with Giemsa. Images courtesy of the Centers for Disease Control and Prevention.

Pathophysiology

T vaginalis principally infects the squamous epithelium of the genital tract. Incubation time is generally between 4 and 28 days.^2,3 Infection may persist for long periods in females but generally persists less than 10 days in males. Anecdotal evidence suggests that asymptomatic infection may persist for months or even years in women.⁴

Infection produces immunity that at best is only partially protective. There is evidence of lymphocyte priming as shown by the presence of antigen-specific peripheral blood mononuclear cells.² An antibody response locally and in serum has also been detected. Despite the interaction that the human immune system has with T vaginalis, there is little evidence that it prevents infection. One study showed no association between trichomoniasis and the use of protease inhibitors or immune status in HIV women.⁵ Another study showed that human immunodeficiency virus (HIV) seropositivity does not alter the rate of infection in males.⁶

Frequency

United States

• An estimated 7.4 million new cases of trichomoniasis occur per year in the United States.⁷
• The prevalence in adolescents is reported to be 2.3%⁸ and 3.1% in women aged 14-49 years⁹ .  
• The reported prevalence in inner-city STD clinics approaches 25%.² Other high-risk populations have very high prevalence rates reported. In two samples of female prison inmates, the prevalence was 31.2-46.9%.^10,11
• Exact numbers are difficult to obtain, as the infection is not nationally reportable, and many infections are asymptomatic. Prevalence is also typically underestimated due to the poor sensitivity of diagnostic tests.

International

The World Health Organization estimates that the burden of trichomonal infection is 174 million cases. ¹²

Mortality/Morbidity

• In females, vaginitis is the most common manifestation of infection. Other complications include infection of the adnexa, endometrium, and Skene and Bartholin glands.
• Males are usually asymptomatic. When symptoms are present, they usually manifest as urethritis. Up to 11% of nongonococcal urethritis cases in men are caused by T vaginalis.¹³ Other complications include infection of the prostate, foreskin, glans, and epididymis.
• T vaginalis has been found in the bronchoalveolar lavage fluid taken from patients with Pneumocystis pneumonia¹⁴ and acute respiratory distress syndrome.¹⁵ In this setting, the organism appears amoeboid, without the presence of flagella.
• Trichomonal sinus disease has been reported in a previously healthy adolescent following multiple trauma who had previously engaged in oral-to-genital sexual activity.
• Infection with T vaginalis is a marker of high-risk sexual behavior. Co-infection with other STDs is common. In one study of adolescents that had a diagnosis of at least one STD, there was almost a 9-fold increase in the likelihood of T vaginalis infection in the ensuing 3 months.¹⁶
• Infection with T vaginalis may increase the rate of infection or reactivation with human papillomavirus, although it may shorten the duration of infection.¹⁷
• Trichomoniasis predisposes one to infection with HIV. Infection with HIV increases one's infectiveness for transmitting T vaginalis.
  • Cheeson et al estimates that 747 new HIV cases a year in women alone are a result of the facilitative effects of T vaginalis on the transmission of the HIV virus.¹⁸
  • Symptomatic males with T vaginalis and HIV had significantly higher numbers of HIV RNA particles in their seminal fluid.
  • Treatment of trichomoniasis has been shown to decrease the rate of viral shedding in HIV patients.^19,20
• The Vaginal Infections and Prematurity (VIP) Study showed infection with T vaginalis resulted in an increased risk of low birth weight, preterm delivery, and preterm delivery of a low birth weight baby.²¹
• The National Institute of Child Health and Human Development Maternal Fetal Medicine Units Network presented data that suggested that metronidazole treatment of asymptomatic carriers of T vaginalis increased risk of preterm birth.^22,23 This is a controversial conclusion, as the study design did not accurately reflect clinical practice. The investigators used 4 doses of 2 g metronidazole in the treatment of infection, which is significantly higher than what is standard practice. The women included in the study were between 16 and 23 weeks gestational age, suggesting a significant delay in treatment.
• A more recent study by Mann et al²⁴ showed no increased risk of preterm birth with the use of metronidazole for the treatment of trichomoniasis. 
• Increased risk of pelvic inflammatory disease (PID) has been shown in HIV-positive women.²⁵
• Increased risk of posthysterectomy infection including cuff cellulitis, cuff abscess, and wound infection has been documented.²⁶
• An association with cervical intra-epithelial neoplasia has been shown.²⁷
• In males, there is a risk of epididymitis, prostatitis, and decreased sperm cell motility.²⁸
• Systemic immune response was demonstrated in pregnant women infected with T vaginalis. A significant increase in granulocyte-macrophage colony-stimulating factor and C-reactive protein was noted.²⁹

Race

• In an analysis of the National Longitudinal Study of Adolescent Health (Add Health), Miller et al⁸ presented the prevalence of trichomoniasis among adolescents. Significant differences were noted among races: white, 1.2%; Latino, 2.1%; black, 6.9%; Asian, 1.8%; and Native American, 4.1%.
• Differences were also reported by Sutton et al⁹ in their study of women aged 14-49 years: non-Hispanic whites, 1.2%; Mexican Americans, 1.5% and non-Hispanic blacks 13.5%.

Sex

• Trichomoniasis is more common in women than in men.
• The incidence in males has been reported in varying populations to be between 2.8 and 17%.^30,31 This may be underestimated due to the method of detection and the site of specimen collection. Use of multiple sites of the genitourinary tract (urine, urethral swab, and semen) in males has been shown to increase sensitivity.³²
• T vaginalis was detected in 72% of male sexual partners of women with trichomoniasis.³³

Age

• Vertical transmission of T vaginalis during birth is possible and may persist up to 1 year. From 2-17% of female offspring of infected women acquire infection.³⁴
• Unlike other STDs, the incidence of trichomoniasis increases with age.
  • The Add Health Study⁸ found that the prevalence among adolescents aged 18-24 years was 2.3%. For adults 25 years and older, the prevalence was 4%.
  • In a study by Joyner et al³⁰ of 454 men attending an STD clinic in Denver, the prevalence in men younger than 30 years was 0.8% and, for men 30 years and older, the prevalence increased to 5.1%. This difference was thought to be due to age-related enlargement of the prostate gland.

Clinical

History

• Nearly half of infected women and almost all infected males are asymptomatic.^3,35
• Presenting signs and symptoms may include vaginal or urethral discharge, odor, irritation, itch, dysuria, abdominal pain, and dyspareunia.^2,29
• One third of asymptomatic women become symptomatic within 6 months.³
• Males are divided into 3 groups: asymptomatic carrier state, acute trichomoniasis, and mild symptomatic disease.³

Physical

• Vaginal discharge is found in 42% of infected women.²
  • The discharge is classically described as thin and frothy; however, this is only seen in about 10% of patients.²
  • The discharge is often yellow. Sometimes, it is thick enough to be confused with candidiasis.
• Abnormal vaginal odor was found in 50% of infected women.²
• Edema or erythema was found in 22-37% of infected women.²
• Vaginal pH is often elevated (>4.5).³⁶
• Colpitis macularis (strawberry cervix) is the finding of punctate hemorrhages and occasionally vesicles or papules on the cervix. It is the most specific clinical sign for the diagnosis of trichomoniasis. Without colposcopy, it is seen in less than 5% of cases. With the use of colposcopy, it is seen in nearly half.³⁷
• In males, if symptomatic, there is usually only scant, thin discharge.
• The clinician's ability to accurately diagnose T vaginalis infection based on physical findings alone was shown in one study to have a positive predictive value of only 47%.³⁸

Causes

Trichomoniasis is caused by the flagellated protozoan Trichomonas vaginalis.

• Risk factors for T vaginalis include the following:
  • Infection with other STDs, especially gonorrhea
  • Four or more lifetime sex partners
  • Sexual contact with an infected partner
  • Not using barrier contraception
  • Trading sex for money or drugs

Differential Diagnoses

Other Problems to Be Considered

Chemical vulvovaginitis
Allergic vulvovaginitis
Foreign body
Cervical, vaginal, and vulvar neoplasia
Epididymitis
Orchitis
Tubo-ovarian abscess

Workup

Laboratory Studies

Given the poor reliability of history and physical findings for the diagnosis of trichomoniasis, laboratory tests are of increased importance. Most clinics and hospitals do not have these tests available. Of the 100 Public Health Laboratories responding to a survey, only 6 reported performing testing for trichomoniasis. None of those responding reported using any of the newer techniques for detection.³⁹ In a follow-up study in 2004, only 4 of 114 Public Health Laboratories tested for trichomoniasis.⁴⁰

• Whiff test
  • Perform the amine odor test by mixing several drops of 10% potassium hydroxide (KOH) to a sample of vaginal discharge. A strong fishy odor is indicative of a positive test result.
  • This test may be positive for either trichomoniasis or bacterial vaginosis. This test should not be considered an accurate means of diagnosis for trichomoniasis. It is one of the four parts of Amsel's criteria used⁴¹ to diagnose bacterial vaginosis.
• Wet mount
  • The procedure is performed by placing a small amount of vaginal discharge on a microscope slide and mixing with a few drops of saline solution. The slide is then examined under a microscope at low or medium power.
  • Presence of flagellated, pyriform protozoa indicates a positive test result.
  • Slides should be read immediately after collection. Kingston et al⁴² looked at samples that were positive for trichomonads on initial reading and then reevaluated every 10 minutes. At 10 minutes, 20% of samples became negative, 35% were negative by 30 minutes, and 78% by 2 hours.
  • Sensitivity is poor, 50-70%.^43,44
  • Sensitivity may be increased by using cervical vaginal lavage.⁴⁵
    • In this modification, 5 mL of sterile saline is injected toward the cervix. Using a pipette, the cervix is bathed 2-3 times prior to drawing up the fluid from the posterior vaginal fornix.
    • Sensitivity was increased to 74.4% versus 54.7% for vaginal swab alone.
  • A short downloadable video is available from the Seattle STD/HIV Prevention Training Center located here.⁴⁶
• Papanicolaou smear: Sensitivity is similar to wet mount, 60%.^47,48
• OSOM Trichomonas Rapid Test (Genzyme Diagnostics, Cambridge, Massachusetts)
  • OSOM Trichomonas Rapid Test uses color immunochromatographic "dipstick" technology with murine monoclonal antibodies.
  • Results are read within 10 minutes.
  • Freezing and transportation of specimens does not appreciably alter the test results.
  • In a comparison to a composite reference standard of wet mount microscopy and culture, the sensitivity was 83.3% and specificity was 98.8%.⁴⁹
  • Another study found a sensitivity of 82% compared with a composite reference standard of wet mount, culture, rapid antigen testing, and polymerase chain reaction (PCR).⁵⁰
• BD Affirm VPIII Microbial Identification Test (BD Diagnostic Systems, Sparks, Maryland)
  • This test uses nucleic acid hybridization technology.
  • It tests for the presence of Trichomonas, Gardnerella, and Candida species.
  • In this procedure, the sample is treated with lysis solution and heated. This ruptures the walls of the organisms present and releases their nucleic acid. Buffer solution is then added to stabilize the nucleic acid. The sample is then added to the first well of the reagent cassette along with the probe analysis card. Hybridization to the capture probe occurs in this first well. In the second well, hybridization to the color development probe occurs. Unbound specimen is washed away in well 3. In the next well, enzyme conjugate binds to the hybridized nucleic acid. In the next two wells, the unbound enzyme conjugate is washed away. In the last well, the indicator substrate is converted to a blue-colored product if bound enzyme conjugate is present on the bead.
  • Sensitivity is between 90% and 100%.⁵¹
• Culture
  • Typically performed in Diamond's medium (Klaas modification), which is superior to Kupferberg's STS medium.⁵²
  • InPouch TV Culture System (Biomed, White City, Oregon)
    • This is a combined wet mount and culture kit.
    • The clinician inoculates the upper chamber of the pouch with a cotton swab. The pouch can be kept at room temperature for up to 18 hours without significant alteration of sensitivity.
    • In the laboratory, a viewing clamp is placed across the upper chamber and examined under a microscope at 100X magnification. If no trichomonads are viewed, the bottom chamber is inoculated by using the medium from the upper chamber. The InPouch is incubated at 37°C and viewed at regular intervals.
    • The InPouch TV Culture System has a sensitivity of 81-100%.⁵³
    • This test may detect as few as one parasite in the sample.
    • Samples taken during menses were not adversely affected.
• Polymerase chain reaction
  • PCR is based on DNA amplification and detection using known primers to Tv specific genes.
  • No approved PCR tests are available for general use, limiting it to research studies only.
  • Sensitivities and specificities of PCR tests for T vaginalis have been demonstrated to be more than 95%.^54,55
  • In males, performing PCR on urine sediment rather than urethral swabs improves detection rates.⁵⁶
  • First-void urines have improved sensitivities.

Other Tests

• Patients should be tested for other STDs/HIV.
• Urinalysis
• Pregnancy test

Treatment

Emergency Department Care

Trichomoniasis is usually diagnosed in outpatient or emergency department settings. Treatment should be instituted immediately and, when possible, in conjunction with all sexual partners. Because of the high co-infection rate with other STDs, the health care provider should consider empiric treatment of gonorrhea and chlamydia. Patients should also be offered counseling and testing for HIV.

Consultations

• For patients with treatment failure and in whom reinfection is ruled out, the Centers for Disease Control and Prevention (CDC) can be consulted (tel: 770-488-4115).
• Infectious diseases specialist
• Gynecologist

Medication

Nitroimidazoles are a class of drugs used to fight a variety of parasitic and anaerobic bacterial infections. The drug is taken up by target organisms and reduced to its active form. The reduced drug then disrupts the helical structure of the DNA within these microbes preventing nucleic acid synthesis and eventually leading to cell death.

A number of clinical trials and meta-analyses have not demonstrated teratogenic effects of metronidazole.^57,58 The CDC currently recommends that symptomatic pregnant females be counseled regarding the risks and benefits of treatment stating that some experts defer treatment until after 37 weeks' gestation.⁵⁹

Patients allergic to this class of drug should be referred to an allergist for desensitization.

• Metronidazole is the treatment of choice for trichomoniasis.
  • Single-dose therapy with 2 g orally is as effective as prolonged therapy with 500 mg twice a day for 7 days.
  • Single-dose therapy increases compliance.
  • Metronidazole gel is effective in less than half the cases of trichomoniasis.⁵⁸
  • Treatment failure with metronidazole increased from 0.4% to 3.5% between 1999 and 2002.⁶⁰
  • Reports now describe resistance to metronidazole approaching 5-10%.
  • If treatment with either single-dose or multi-dose therapy fails, the patient should be treated with 500 mg orally twice a day for 7 days. If this fails, the patient should take 2 g orally daily for 3-5 days.
  • Metronidazole is pregnancy class B; animal studies have revealed no evidence of harm to the fetus.
  • In lactating women, it is suggested that breastfeeding be withheld until 12-24 hours after the last dose to reduce exposure to the infant.⁵⁹
• Tinidazole
  • Single-dose therapy is 2 g taken with food.
  • For resistant infections, one recommendation is to use 2 g twice daily for 14 days.⁶¹
  • Cure rates are from 83-100%.
  • Tinidazole has been available outside the United States for more than 25 years.
  • Tinidazole was approved by the US Food and Drug Administration in May 2004.
  • Tinidazole has a longer half-life (12-14 h) than metronidazole (6-7 h).
  • In a case series by Hager et al, all 3 patients who failed 3 regimens of metronidazole therapy were cured by tinidazole.⁶²
  • Tinidazole is pregnancy class C; animal studies have demonstrated adverse effects on fetal development.
  • In lactating women, it is recommended that breastfeeding be withheld until 3 days after the last treatment.⁵⁹
• Clotrimazole vaginal tablets have been used in the past. In a study by duBouchet et al in 1997, the cure rate was only 11% with this mode of therapy.⁶³

Antiprotozoals

These agents may bind DNA and inhibit protein synthesis, causing cell death. In the drug tinidazole, the free nitro radical generated during metabolism is thought to be responsible for antiprotozoal. However, the exact mechanisms of many antiprotozoal agents are not well understood.

Metronidazole (Flagyl)

Active against various anaerobic bacteria and protozoa; mode of action not well understood; appears to be absorbed into cells; intermediate-metabolized compounds formed bind DNA and inhibit protein synthesis, causing cell death.
Metronidazole is treatment of choice.
Single-dose therapy with 2 g PO is as effective as prolonged therapy with 500 mg bid for 7 d.
Single-dose therapy increases compliance.
Metronidazole gel is effective in less than half the cases of trichomoniasis.
Now reports of resistance to metronidazole approaching 5-10% exist.
If treatment with either single-dose or multi-dose therapy fails, patient should be treated with 500 mg PO bid for 7 d. If this fails, patient should take 2 g PO qd for 3-5 d.

Dosing

Adult

2 g PO in single dose or 500 mg PO bid for 7 d

Pediatric

15-30 mg/kg/d PO divided bid/tid for 7 d or 40 mg/kg PO in single dose; not to exceed 500 mg/dose

Interactions

Potentiates anticoagulant effect of warfarin; may increase effects of anticoagulants; may decrease lithium and phenytoin clearance, increasing toxicity; half-life may be decreased by agents that alter the hepatic P450 system (ie, phenytoin, phenobarbital); clearance may be decreased and toxicity increased by cimetidine; disulfiramlike reaction may occur when used concurrently with orally ingested ethanol; although risk for most patients may be slight, caution is advised

Contraindications

Documented hypersensitivity

Precautions

Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals

Precautions

Because metronidazole crosses the placenta, many physicians avoid using it during first trimester of pregnancy; adjust dose in patients with severe hepatic disease, since they may metabolize metronidazole slowly; monitor patients for seizures and development of peripheral neuropathy

Tinidazole (Tindamax)

5-nitroimidazole derivative used for susceptible protozoal infections. Nitro group is reduced by cell extract of Trichomonas. The free nitro radical generated is thought to be responsible for antiprotozoal activity against T vaginalis. Indicated to treat trichomoniasis caused by T vaginalis in both males and females.
Single-dose therapy of 2 g taken with food. Cure rates from 83-100%.
Available outside US for more than 25 years.
Approved by the FDA in May 2004.
Has a longer half-life (12-14 h) than metronidazole (6-7 h).
In a case series by Hager et al, all 3 patients who failed 3 regimens of metronidazole therapy were cured by tinidazole.⁶²

Dosing

Adult

Individual and sexual partner: 2 g PO once ac

Pediatric

Adolescents: 1.5 g PO once ac

Interactions

Limited data exist; interaction information based on experience with other nitroimidazole derivatives (ie, metronidazole); may prolong PT when coadministered with warfarin; avoid alcoholic beverages and preparations containing ethanol or propylene glycol during and 3 d following administration (may cause disulfiramlike reaction); may increase serum levels of lithium, phenytoin, cyclosporine, tacrolimus, and fluorouracil; CYP450 inducers (eg, phenobarbital, rifampin, phenytoin) may increase elimination; CYP450 inhibitors (eg, cimetidine, ketoconazole) may decrease elimination; concurrent administration with cholestyramine may decrease oral bioavailability; oxytetracycline may antagonize effect

Contraindications

Documented hypersensitivity; first trimester of pregnancy

Precautions

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

X - Contraindicated; benefit does not outweigh risk

Precautions

Caution in blood dyscrasias, organic neurologic dysfunction, late trimesters of pregnancy, seizure disorders, and hepatic and renal impairment
Carcinogenicity has been observed in mice and rats treated chronically with metronidazole (another nitroimidazole), although not observed with tinidazole, use cautiously; may cause metallic/bitter taste, nausea, anorexia, vomiting, weakness, fatigue, dizziness, or headache; if administered on day of hemodialysis, administer additional dose equivalent to one-half of recommended dose following dialysis

Follow-up

Further Outpatient Care

• Patients with trichomoniasis who become asymptomatic or who are asymptomatic to begin with do not require routine follow-up.
• Partner testing
• Retesting for infection clearance or given resistance
• Referral for HIV/STD testing

Deterrence/Prevention

• Condom use may be protective against trichomoniasis.
• Circumcision
• Abstinence

Complications

• See Pathophysiology.
• HIV
• Tubo-ovarian abscess

Prognosis

• Recurrent T vaginalis infections occur in up to 30% of patients.

Patient Education

• Upon diagnosis, discuss the importance of treatment and the treatment of partners with the patient. Discuss methods of prevention. It may also be important to explain that the infection may have been long-standing and not due to a recent encounter.
• For patient education resources, see the CDC's Fact Sheet. Also see eMedicineHealth's patient education articles on Trichomoniasis and Sexually Transmitted Diseases.

Miscellaneous

Medicolegal Pitfalls

• Failure to recognize the infection may result in complications in pregnancy. The medicolegal implications are unclear, as it has not been demonstrated that treatment of trichomoniasis reduces the incidence of complications.

Multimedia

Media file 1: Trichomonas vaginalis on a saline wet mount at 40X on the microscope. Several motile parasites transit through the field, surrounded by white blood cells and squamous epithelial cells.

Video available at http://img.medscape.com/pi/emed/ckb/emergency_medicine/756148-780913-787722-1769101.flv.

Media file 2: Life cycle of Trichomonas vaginalis.T vaginalis resides in the female lower genital tract and the male urethra and prostate (1), where it replicates by binary fission (2). The parasite does not appear to have a cyst form and does not survive well in the external environment. T vaginalis is transmitted among humans, its only known host, primarily by sexual intercourse (3). Image courtesy of the Centers for Disease Control and Prevention.

Media file 3: Trichomonas vaginalis. A, Two trophozoites of T vaginalis obtained from in vitro culture, stained with Giemsa. B, Trophozoite of T vaginalis in a vaginal smear, stained with Giemsa. Images courtesy of the Centers for Disease Control and Prevention.

References

1. Eckert J. Protozoa. In: Kayser FH, Bienz KA, Eckert J, et al, eds. Color Atlas of Medical Microbiology. 2^nd ed. New York, NY: Thieme; 2005.

2. Schwebke JR, Burgess D. Trichomoniasis. Clin Microbiol Rev. Oct 2004;17(4):794-803, table of contents. [Medline].

3. Petrin D, Delgaty K, Bhatt R, Garber G. Clinical and microbiological aspects of Trichomonas vaginalis. Clin Microbiol Rev. Apr 1998;11(2):300-17. [Medline].

4. Dan M, Sobel JD. Trichomoniasis as seen in a chronic vaginitis clinic. Infect Dis Obstet Gynecol. 1996;4(2):77-84. [Medline].

5. Magnus M, Clark R, Myers L, Farley T, Kissinger PJ. Trichomonas vaginalis among HIV-Infected women: are immune status or protease inhibitor use associated with subsequent T. vaginalis positivity?. Sex Transm Dis. Nov 2003;30(11):839-43. [Medline].

6. Hobbs MM, Kazembe P, Reed AW, et al. Trichomonas vaginalis as a cause of urethritis in Malawian men. Sex Transm Dis. Aug 1999;26(7):381-7. [Medline].

7. Weinstock H, Berman S, Cates W Jr. Sexually transmitted diseases among American youth: incidence and prevalence estimates, 2000. Perspect Sex Reprod Health. Jan-Feb 2004;36(1):6-10. [Medline].

8. Miller WC, Swygard H, Hobbs MM, et al. The prevalence of trichomoniasis in young adults in the United States. Sex Transm Dis. Oct 2005;32(10):593-8. [Medline].

9. Sutton M, Sternberg M, Koumans EH, McQuillan G, Berman S, Markowitz L. The prevalence of Trichomonas vaginalis infection among reproductive-age women in the United States, 2001-2004. Clin Infect Dis. Nov 15 2007;45(10):1319-26. [Medline].

10. Garcia A, Exposto F, Prieto E, et al. Association of Trichomonas vaginalis with sociodemographic factors and other STDs among female inmates in Lisbon. Int J STD AIDS. Sep 2004;15(9):615-8. [Medline].

11. Shuter J, Bell D, Graham D, Holbrook KA, Bellin EY. Rates of and risk factors for trichomoniasis among pregnant inmates in New York City. Sex Transm Dis. Jul 1998;25(6):303-7. [Medline].

12. World Health Organization. Global Prevalence and Incidence of Selected Curable Sexually Transmitted Infections: Overviews and Estimates. WHO/HIV_AIDS/2001.02. Geneva: World Health Organization. 2001.

13. Kreiger JN. Trichomoniasis in Men: Old Issues and New Data. Sex Trans Dis. 1995;22:83-96.

14. Duboucher C, Boggia R, Morel G, Capron M, Pierce RJ, Dei-Cas E, et al. Pneumocystis pneumonia: immunosuppression, Pneumocystis jirovecii...and the third man. Nat Rev Microbiol. Dec 2007;5(12):[Medline].

15. Duboucher C, Barbier C, Beltramini A, Rona M, Ricome JL, Morel G, et al. Pulmonary superinfection by trichomonads in the course of acute respiratory distress syndrome. Lung. Sep-Oct 2007;185(5):295-301. [Medline].

16. Crosby RA, DiClemente RJ, Wingood GM, et al. Associations between sexually transmitted disease diagnosis and subsequent sexual risk and sexually transmitted disease incidence among adolescents. Sex Transm Dis. Apr 2004;31(4):205-8. [Medline].

17. Watts DH, Fazzari M, Minkoff H, et al. Effects of bacterial vaginosis and other genital infections on the natural history of human papillomavirus infection in HIV-1-infected and high-risk HIV-1-uninfected women. J Infect Dis. Apr 1 2005;191(7):1129-39. [Medline].

18. Chesson HW, Blandford JM, Pinkerton SD. Estimates of the annual number and cost of new HIV infections among women attributable to trichomoniasis in the United States. Sex Transm Dis. Sep 2004;31(9):547-51. [Medline].

19. Wang CC, McClelland RS, Reilly M, et al. The effect of treatment of vaginal infections on shedding of human immunodeficiency virus type 1. J Infect Dis. Apr 1 2001;183(7):1017-22. [Medline].

20. Kissinger P, Amedee A, Clark RA, Dumestre J, Theall KP, Myers L, et al. Trichomonas vaginalis treatment reduces vaginal HIV-1 shedding. Sex Transm Dis. Jan 2009;36(1):11-6. [Medline].

21. Cotch MF, Pastorek JG 2nd, Nugent RP, et al. Trichomonas vaginalis associated with low birth weight and preterm delivery. The Vaginal Infections and Prematurity Study Group. Sex Transm Dis. Jul 1997;24(6):353-60. [Medline].

22. Carey JC and Klebanoff M, for the NICHD MFMU Network. Metronidazole treatment increased the risk of preterm birth in asymptomatic women with Trichomonas. Presented at the 20th Annual Meeting of the Society of Maternal-Fetal Medicine, Miami, FL, February 2000.

23. Klebanoff MA, Carey JC, Hauth JC, et al. Failure of metronidazole to prevent preterm delivery among pregnant women with asymptomatic Trichomonas vaginalis infection. N Engl J Med. Aug 16 2001;345(7):487-93. [Medline].

24. Mann JR, McDermott S, Zhou L, Barnes TL, Hardin J. Treatment of trichomoniasis in pregnancy and preterm birth: an observational study. J Womens Health (Larchmt). Apr 2009;18(4):493-7. [Medline].

25. Moodley P, Wilkinson D, Connolly C, Moodley J, Sturm AW. Trichomonas vaginalis is associated with pelvic inflammatory disease in women infected with human immunodeficiency virus. Clin Infect Dis. Feb 15 2002;34(4):519-22. [Medline].

26. Soper DE, Bump RC, Hurt WG. Bacterial vaginosis and trichomoniasis vaginitis are risk factors for cuff cellulitis after abdominal hysterectomy. Am J Obstet Gynecol. Sep 1990;163(3):1016-21; discussion 1021-3. [Medline].

27. Viikki M, Pukkala E, Nieminen P, Hakama M. Gynaecological infections as risk determinants of subsequent cervical neoplasia. Acta Oncol. 2000;39(1):71-5. [Medline].

28. Martinez-Garcia F, Regadera J, Mayer R, Sanchez S, Nistal M. Protozoan infections in the male genital tract. J Urol. Aug 1996;156(2 Pt 1):340-9. [Medline].

29. Anderson BL, Cosentino LA, Simhan HN, Hillier SL. Systemic immune response to Trichomonas vaginalis infection during pregnancy. Sex Transm Dis. Jun 2007;34(6):392-6. [Medline].

30. Joyner JL, Douglas JM Jr, Ragsdale S, Foster M, Judson FN. Comparative prevalence of infection with Trichomonas vaginalis among men attending a sexually transmitted diseases clinic. Sex Transm Dis. Apr 2000;27(4):236-40. [Medline].

31. Schwebke JR, Hook EW 3rd. High rates of Trichomonas vaginalis among men attending a sexually transmitted diseases clinic: implications for screening and urethritis management. J Infect Dis. Aug 1 2003;188(3):465-8. [Medline].

32. Kaydos-Daniels SC, Miller WC, Hoffman I, et al. The use of specimens from various genitourinary sites in men, to detect Trichomonas vaginalis infection. J Infect Dis. May 15 2004;189(10):1926-31. [Medline].

33. Hobbs MM, Lapple DM, Lawing LF, et al. Methods for detection of Trichomonas vaginalis in the male partners of infected women: implications for control of trichomoniasis. J Clin Microbiol. Nov 2006;44(11):3994-9. [Medline].

34. Danesh IS, Stephen JM, Gorbach J. Neonatal Trichomonas vaginalis infection. J Emerg Med. Jan-Feb 1995;13(1):51-4. [Medline].

35. Fouts AC, Kraus SJ. Trichomonas vaginalis: reevaluation of its clinical presentation and laboratory diagnosis. J Infect Dis. Feb 1980;141(2):137-143. [Medline].

36. Bell C, Hough E, Smith A, Greene L. Targeted screening for Trichomonas vaginalis in women, a pH-based approach. Int J STD AIDS. Jun 2007;18(6):402-3. [Medline].

37. Wolner-Hanssen P, Krieger JN, Stevens CE, Kiviat NB, Koutsky L, Critchlow C, et al. Clinical manifestations of vaginal trichomoniasis. JAMA. Jan 27 1989;261(4):571-6. [Medline].

38. Ryan KA, Zekeng L, Roddy RE, et al. Prevalence and Prediction of Sexually Transmitted Disease Among Sex Workers in Cameroon. Int H STD AIDS. 1998;9:403-7.

39. Dicker LW, Mosure DJ, Steece R, Stone KM. Laboratory tests used in US public health laboratories for sexually transmitted diseases, 2000. Sex Transm Dis. May 2004;31(5):259-64. [Medline].

40. Dicker LW, Mosure DJ, Steece R, Stone KM. Testing for sexually transmitted diseases in U.S. Public health laboratories in 2004. Sex Transm Dis. Jan 2007;34(1):41-6. [Medline].

41. Amsel R, Totten PA, Spiegel CA, Chen KC, Eschenbach D, Holmes KK. Nonspecific vaginitis. Diagnostic criteria and microbial and epidemiologic associations. Am J Med. Jan 1983;74(1):14-22. [Medline].

42. Kingston MA, Bansal D, Carlin EM. 'Shelf life' of Trichomonas vaginalis. Int J STD AIDS. Jan 2003;14(1):28-9. [Medline].

43. Krieger JN, Tam MR, Stevens CE, Nielsen IO, Hale J, Kiviat NB, et al. Diagnosis of trichomoniasis. Comparison of conventional wet-mount examination with cytologic studies, cultures, and monoclonal antibody staining of direct specimens. JAMA. Feb 26 1988;259(8):1223-7. [Medline].

44. Radonjic IV, Dzamic AM, Mitrovic SM, Arsic Arsenijevic VS, Popadic DM, Kranjcic Zec IF. Diagnosis of Trichomonas vaginalis infection: The sensitivities and specificities of microscopy, culture and PCR assay. Eur J Obstet Gynecol Reprod Biol. May 1 2006;126(1):116-20. [Medline].

45. Kissinger PJ, Dumestre J, Clark RA, et al. Vaginal swabs versus lavage for detection of Trichomonas vaginalis and bacterial vaginosis among HIV-positive women. Sex Transm Dis. Apr 2005;32(4):227-30. [Medline].

46. Seattle STD/HIV Prevention Training Network. Examination of Vaginal Wet Preps. Available at http://depts.washington.edu/nnptc/online_training/wet_preps_video.html. Accessed Dec 30, 2005.

47. Lobo TT, Feijo G, Carvalho SE, et al. A comparative evaluation of the Papanicolaou test for the diagnosis of trichomoniasis. Sex Transm Dis. Sep 2003;30(9):694-9. [Medline].

48. Lara-Torre E, Pinkerton JS. Accuracy of detection of trichomonas vaginalis organisms on a liquid-based papanicolaou smear. Am J Obstet Gynecol. Feb 2003;188(2):354-6. [Medline].

49. Huppert JS, Batteiger BE, Braslins P, et al. Use of an immunochromatographic assay for rapid detection of Trichomonas vaginalis in vaginal specimens. J Clin Microbiol. Feb 2005;43(2):684-7. [Medline].

50. Huppert JS, Mortensen JE, Reed JL, et al. Rapid antigen testing compares favorably with transcription-mediated amplification assay for the detection of Trichomonas vaginalis in young women. Clin Infect Dis. Jul 15 2007;45(2):194-8. [Medline].

51. Nye MB, Schwebke JR, Body BA. Comparison of APTIMA Trichomonas vaginalis transcription-mediated amplification to wet mount microscopy, culture, and polymerase chain reaction for diagnosis of trichomoniasis in men and women. Am J Obstet Gynecol. Feb 2009;200(2):188.e1-7. [Medline].

52. Gelbart SM, Thomason JL, Osypowski PJ, Kellett AV, James JA, Broekhuizen FF. Growth of Trichomonas vaginalis in commercial culture media. J Clin Microbiol. May 1990;28(5):962-4. [Medline].

53. Ohlemeyer CL, Hornberger LL, Lynch DA, Swierkosz EM. Diagnosis of Trichomonas vaginalis in adolescent females: InPouch TV culture versus wet-mount microscopy. J Adolesc Health. Mar 1998;22(3):205-8. [Medline].

54. Madico G, Quinn TC, Rompalo A, McKee KT Jr, Gaydos CA. Diagnosis of Trichomonas vaginalis infection by PCR using vaginal swab samples. J Clin Microbiol. Nov 1998;36(11):3205-10. [Medline].

55. Mayta H, Gilman RH, Calderon MM, et al. 18S ribosomal DNA-based PCR for diagnosis of Trichomonas vaginalis. J Clin Microbiol. Jul 2000;38(7):2683-7. [Medline].

56. Schwebke JR, Lawing LF. Improved detection by DNA amplification of Trichomonas vaginalis in males. J Clin Microbiol. Oct 2002;40(10):3681-3. [Medline].

57. Burtin P, Taddio A, Ariburnu O, Einarson TR, Koren G. Safety of metronidazole in pregnancy: a meta-analysis. Am J Obstet Gynecol. Feb 1995;172(2 Pt 1):525-9. [Medline].

58. Diav-Citrin O, Shechtman S, Gotteiner T, Arnon J, Ornoy A. Pregnancy outcome after gestational exposure to metronidazole: a prospective controlled cohort study. Teratology. May 2001;63(5):186-92. [Medline].

59. [Guideline] Workowski KA, Berman SM. Sexually transmitted diseases treatment guidelines, 2006. MMWR Recomm Rep. Aug 4 2006;55:1-94. [Medline].

60. Das S, Huengsberg M, Shahmanesh M. Treatment failure of vaginal trichomoniasis in clinical practice. Int J STD AIDS. Apr 2005;16(4):284-6. [Medline].

61. Mammen-Tobin A, Wilson JD. Management of metronidazole-resistant Trichomonas vaginalis--a new approach. Int J STD AIDS. Jul 2005;16(7):488-90. [Medline].

62. Hager WD. Treatment of metronidazole-resistant Trichomonas vaginalis with tinidazole: case reports of three patients. Sex Transm Dis. Jun 2004;31(6):343-5. [Medline].

63. duBouchet L, Spence MR, Rein MF, Danzig MR, McCormack WM. Multicenter comparison of clotrimazole vaginal tablets, oral metronidazole, and vaginal suppositories containing sulfanilamide, aminacrine hydrochloride, and allantoin in the treatment of symptomatic trichomoniasis. Sex Transm Dis. Mar 1997;24(3):156-60. [Medline].

64. Anderson MR, Klink K, Cohrssen A. Evaluation of vaginal complaints. JAMA. Mar 17 2004;291(11):1368-79. [Medline].

65. Pillay A, Lewis J, Ballard RC. Evaluation of Xenostrip-Tv, a rapid diagnostic test for Trichomonas vaginalis infection. J Clin Microbiol. Aug 2004;42(8):3853-6. [Medline].

Keywords

trichomoniasis, trichomonas, STD, sexually transmitted disease, vaginitis, urethritis, infection of the adnexa, infection of the endometrium, infection of the Skene glands, infection of the Bartholin glands, nongonococcal urethritis, infection of the prostate, infection of the foreskin, infection of the glans, infection of the epididymis, cervicitis, pelvic inflammatory disease

Contributor Information and Disclosures

Author

R Gentry Wilkerson, MD, Clinical Assistant Professor, Department of Emergency Medicine, State University of New York-Downstate; Attending Physician, Department of Emergency Medicine, Kings County Hospital
R Gentry Wilkerson, MD is a member of the following medical societies: American Academy of Emergency Medicine and American College of Emergency Physicians
Disclosure: Nothing to disclose.

Coauthor(s)

Richard H Sinert, DO, Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center
Richard H Sinert, DO is a member of the following medical societies: American College of Physicians and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Benjamin W Friedman, MD, Staff Physician, Department of Emergency Medicine, Jacobi/Montefiore Medical Centers
Benjamin W Friedman, MD is a member of the following medical societies: American Academy of Emergency Medicine and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Judith C Brillman, MD, Professor, Department of Emergency Medicine, Assistant Dean, Graduate Medical Education, University of New Mexico School of Medicine
Judith C Brillman, MD is a member of the following medical societies: American Academy of Emergency Medicine, American Association of Women Emergency Physicians, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Medical Editor

Theodore J Gaeta, DO, MPH, FACEP, Clinical Associate Professor, Department of Emergency Medicine, Joan and Sanford Weill Medical College at Cornell University; Vice Chairman and Program Director of Emergency Medicine Residency Program, Department of Emergency Medicine, New York Methodist Hospital; Academic Chair, Adjunct Professor, Department of Emergency Medicine, St George's University School of Medicine
Theodore J Gaeta, DO, MPH, FACEP is a member of the following medical societies: Alliance for Clinical Education, American College of Emergency Physicians, Clerkship Directors in Emergency Medicine, Council of Emergency Medicine Residency Directors, New York Academy of Medicine, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

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Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Mark L Plaster, MD, JD, Executive Editor, Emergency Physicians Monthly
Mark L Plaster, MD, JD is a member of the following medical societies: American Academy of Emergency Medicine and American College of Emergency Physicians
Disclosure: M L Plaster Publishing Co LLC Ownership interest Management position

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
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Chief Editor

Rick Kulkarni, MD, Assistant Professor of Surgery, Section of Emergency Medicine, Yale-New Haven Hospital
Rick Kulkarni, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, American College of Emergency Physicians, American Medical Association, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
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The authors and editors of eMedicine gratefully acknowledge the medical review of this article by Joseph U Becker, MD.

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