Trichomoniasis: Introduction, Symptoms, Risk factors, Lab diagnosis, Treatment and Prevention
Introduction of trichomoniasis
Trichomoniasis is a sexually transmitted infection. A protozoan parasite, Trichomonas vaginalis is a causative agent of this infection that is very common. and easily treatable. T. vaginalis travels from person to person through genital contact during sex. In women, the organism causes an infection in the vagina, urethra, or both. In men, the infection only happens in the urethra. Once the infection begins, it can easily be spread through unprotected genital contact whereas it is not transmitted through normal physical contact such as hugging, kissing, sharing dishes, or sitting on a toilet seat.
Scientific classification
Phylum: Metamonada
Order: Trichomonadida
Family: Trichomonadidae
Genus: Trichomonas
Species: T. vaginalis
Binomial name: Trichomonas vaginalis
Features of Trichomonas
Parasite of tropics. It exists in the trophozoites phase and there is no cystic stage. There is a single ovoid nucleus striated at the anterior end and cleft-like depression( cytosome) lies at its side. There are 3-5 flagella that are free. However, thick flagellum passes backward by the side of the body forming an undulating membrane. The undulating membrane is supported at the base by a rod-like structure called costa. The axostyle runs down the middle of the body and ends in the pointed tail-like extremity.
Virulence factors of Trichomonas
A variety of virulence factors mediate this process some of which are the microtubules, microfilaments, bacterial adhesins, and cysteine proteinases. These four adhesins are trichomonad enzymes that mediate the interaction of the parasite to the receptor molecules on vaginal epithelial cells. Cysteine proteinases may be another virulence factor because not only do these 30 kDa proteins bind to host cell surfaces but also may degrade extracellular matrix proteins like hemoglobin, fibronectin, or collagen IV.
Symptoms of trichomoniasis
It often has no symptoms. When symptoms do occur, they often begin five to 28 days after a person is infected. Although for some people it can take much longer.
Common symptoms among women are-
- vaginal discharge maybe with white, gray, yellow, or green, and usually frothy with an unpleasant smell
- vaginal bleeding
- genital burning or itching
- genital swelling
- frequent urination
- pain during sexual intercourse as well as urination
common symptoms in men are- - discharge from the urethra
- burning during urination as well as after ejaculation
- frequent urination
Risk factors of Trichomoniasis
Your risk of trichomoniasis infection can increase due to having-
- multiple sexual partners
- sex without a condom
- a history of other STIs
- previous trichomoniasis infections
Lab Diagnosis of Trichomoniasis
Clinical diagnosis alone is difficult to diagnose due to having similar symptoms to those of other sexually transmitted infections (STIs). Laboratory diagnosis is very useful in this scenario for your clinician i.e. doctor.
Direct evidence
Presence of trophozoites in vaginal fluid ( women) during saline microscopy of this specimen
Similarly, the Presence of trophozoites in urethral discharge ( men) during saline microscopy of this specimen
Other methods of diagnosis are-
Culture of organism
Antigen detection
Treatment of trichomoniasis
The choice of drug for the treatment of trichomoniasis is either metronidazole or tinidazole. Note: You should take some precautions during medication of these drugs or antibiotics i.e do not drink any alcohol for the first 24 hours after taking metronidazole or the first 72 hours after taking tinidazole because of causing severe nausea and vomiting. Similarly, another important point, make sure your sexual partners are properly tested and take the medication, too. Not having any symptoms doesn’t mean they don’t have the infection. You will need to avoid sexual intercourse for a week after all partners have been treated.
Prevention of trichomoniasis
- Use latex condoms during sexual intercourse to reduce your chances of contracting trichomoniasis.
- Avoiding sexual contact
Further Readings
- Merkell and Voge’s medical parasitology
9th edition. - Parasitology: 12th edition
By K. D. Chatterjee - District laboratory practice in Tropical countries –Part-I.
By Monica Chesbrough. - Isenberg clinical microbiology procedures Handbook
2nd edition. Vol. 2 - Atlas of Medical Helminthology and protozoology -4th edn -P.L. Chiodini, A.H. Moody, D.W. Manser
- Medical Parasitology by Abhay R. Satoskar, Gary L. Simon, Peter J. Hotez and Moriya Tsuji
- Atlas of Human Parasitology, Lawrence R Ash, Thomas C. Orihel, 3 rd ed, Publisher ASCP Press, Chicago.
- Molecular Medical Parasitology. Editors: J. Joseph Marr, Timothy W. Nilsen, and Richard W. Komuniecki, Publisher Academic Press, an imprint of Elsevier Science.
- Topley & Wilsons’ Principle of parasitology. Editors: M.T. Parker & L.H. Collier, 8 th ed 1990, Publisher Edward Arnold publication, London.
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