Cervix
Inflammatory / infectious
Trichomonas vaginalis
Authors: Soumya Jaladi, M.B.B.S., Ziyan T. Salih, M.D.
Editorial Board Member: David B. Chapel, M.D.
Deputy Editor-in-Chief: Jennifer A. Bennett, M.D.
Last author update: 22 August 2022
Last staff update: 1 May 2024
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed Search: Trichomonas vaginalis
Table of Contents
Definition / general | Essential features | Terminology | Epidemiology | Sites | Pathophysiology | Etiology | Diagrams / tables | Diagnosis | Prognostic factors | Case reports | Treatment | Prevention | Clinical images | Cytology description | Cytology images | Electron microscopy images | Sample pathology report | Differential diagnosis | Additional references | Board review style question #1 | Board review style answer #1 | Board review style question #2 | Board review style answer #2Cite this page: Jaladi S, Salih ZT. Trichomonas vaginalis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cervixtrichomonasvaginalis.html. Accessed December 25th, 2024.
Definition / general
- Trichomonas vaginalis is a primitive eukaryotic organism, a parasitic protozoan that causes trichomoniasis, which is a sexually transmitted disease
- Sometimes accompanied by Leptothrix (a nonpathogenic, long, filamentous bacterium)
Essential features
- Pear shaped primitive eukaryotic organism, a parasitic protozoan
- Primarily a disease of woman, though it also occurs in men
- Clusters of the organisms are colloquially called trich parties
Terminology
- Trichomonas vaginalis
Epidemiology
- Trichomoniasis is the most prevalent nonviral sexually transmitted infection in the United States, affecting an estimated 3.7 million persons (CDC: Trichomoniasis [Accessed 29 July 2022])
- Having multiple sexual partners is the primary risk factor
- Mainly affects women from ages 16 - 35 years but can occur in postmenopausal women
- Trichomonas vaginalis infection is strongly associated with an increased risk of HIV acquisition and transmission, particularly among women (Sex Transm Dis 2016;43:617)
Sites
- Female: lower genital tract (vulva, vagina, cervix or urethra)
- Male: urethra, epididymis and prostate
Pathophysiology
- Unclear why some people with the infection get symptoms while others do not
- Likely depends on factors such as a person's age and overall health
Etiology
- Sexually active people can get trichomoniasis by having sex without a condom with a partner who has trichomoniasis infection
Diagrams / tables
Images hosted on other servers:
Trophozoite
Diagnosis
- Nucleic acid amplification test (NAAT) is the gold standard for diagnosis of trichomoniasis (Can J Infect Dis Med Microbiol 2005;16:35)
- OSOM Trichomonas rapid test: immunochromatographic test that detects pathogen antigens from vaginal swab
- DNA hybridization probe test
- Direct microscopic examination of secretions - wet mount
- Culture was considered as a gold standard before the availability of molecular tests
Prognostic factors
- Person's age and overall health
- People with trichomoniasis can pass the infection to others, even if they do not have symptoms
Case reports
- 18 year old woman with vaginal discharge (Lablogatory: Microbiology Case Study - An 18 Year Old with Vaginal Discharge [Accessed 29 July 2022])
- 22 year old woman with untreated trichomoniasis (J Reprod Med 2008;53:59)
- 29 year old man presenting with Trichomonas vaginalis associated with chronic penile ulcers and multiple urethral fistulas (Am J Trop Med Hyg 2015;92:943)
Treatment
- Patients and their sexual partners are treated with metronidazole or tinidazole (CDC: Trichomoniasis [Accessed 29 July 2022])
- Reinfection occurs in about 1 in 5 people within 3 months after receiving treatment
Prevention
- Condoms can reduce the risk of getting trichomoniasis if used the right way every single time
Clinical images
Images hosted on other servers:
Strawberry cervix
Cytology description
- Organism is a 15 - 30 μm, pear shaped protozoan
- Nucleus is small, very pale, eccentrically placed
- Cytoplasm often contains tiny red granules
- Clusters of the organisms are colloquially called trich parties
- Sometimes accompanied by Leptothrix, a nonpathogenic, long, filamentous bacterium (Bibbo: Comprehensive Cytopathology, 4th Edition, 2014)
- Trichomonas and Leptothrix together have been referred to as spaghetti and meatballs
- Leptotrichia and Trichomonas were observed together in 95% of cases in a study of 1,000 cases (Clin Microbiol Rev 1998;11:341)
- 3 dimensional clusters of neutrophils (poly balls) may be seen in the background
- Numerous lymphocytes and many mast cells may be seen
Cytology images
Contributed by Soumya Jaladi, M.B.B.S., Marilin Rosa, M.D., @zaalruwai83 and @DrVasudevPrabhu on Twitter
Trichomonas in a cytologic preparation
Trichomonas
Trichomonas vaginalis
Trichomonas vaginalis
Trichomonas vaginalis
Images hosted on other servers:
Filamentous Leptothrix species
Trichomonas in wet mount
Trichomonas in conventional
Pap smear
Trichomonas vaginalis with Leptothrix
Trichomonas
Trophozite
Inflammatory ectocervix with Trichomonas infection
Electron microscopy images
Images hosted on other servers:
T. vaginalis parasite
Sample pathology report
- Cervix, smear:
- Squamous cells with background inflammatory cells and pear shaped organisms with eccentric nuclei, consistent with Trichomonas
Differential diagnosis
- Cell fragments, cytoplasmic debris, bare epithelial nuclei, small mucus aggregates and leukocytes:
- Identification of a definite elliptical nucleus helps avoid misinterpretation
- Presence of eosinophilic cytoplasmic granules will be helpful
- In most cases, Trichomonas organisms are plentiful (trich party)
Additional references
Board review style question #1
What are the organisms frequently identified in cytologic smears in patients with Trichomonas infections?
- Candida
- Herpes
- Leptothrix
- Sporothrix
Board review style answer #1
Board review style question #2
What is the gold standard test for diagnosis of trichomoniasis?
- DNA hybridization probe test
- Immunochromatographic test
- Nucleic acid amplification test (NAAT)
- Wet mount microscopic examination
Board review style answer #2
