The subsequent sections provide an overview regarding this infection.
The common type of vaginitis is caused by the trichomonas vaginalis (T. vaginalis), an anaerobic parasitic flagellated protozoan. The T. vaginalis trophozoite has five flagella arising near the cytosome. Four of the said flagella extend outside the cell collectively. The fifth flagellum, the function of which is unknown, wraps backwards along the surface of the organism. Apart from these, a barb-like axostyle, which may be used for attachment to surfaces and cause damage of tissues observed in trichomoniasis infections, protrudes on the opposite of the four-flagella bundle. (Talaro, 2002)
The T. vaginalis has multiple enzymes that catalyze a number of reactions. However, it lacks mitochondria and other necessary enzymes and cytosomes to conduct oxidative phosporylation. This organism survives by obtaining nutrients transported through the cell membrane and via phagocytosis. To maintain energy requirements, it makes use of a small amount of enzymes through glycolysis of glucose to glycerol and succinate in the cytoplasm. These processes are followed by the further conversion of pyruvate and malate to hydrogen and acetate in the hydrogenosome organelle. (Ryan & Ray, 2004)
The normal vaginal flora is maintained by a complex and intricate balance of microorganisms that include lactobacilli, corynebacteria and yeast. In addition, this microenvironment is influenced by hormones. With this, a decrease in estrogen levels, which usually occurs in prepuberty and postmenopause, can result in an increased risk of infection. (Gor, 2006)
It should be noted that growth of pathogenic organisms such as T. vaginalis is inhibited given the normal postmenarchal and premenopausal vaginal pH ranging from 3.8 to 4.2. In this regard, disturbance in the normal vaginal pH can change the vaginal flora resulting in the overgrowth of pathogens. Myriad factors such as the use of feminine hygiene products, contraceptives, vaginal medications, antibiotics and contracting sexually transmitted diseases my bring about the alteration of the vaginal environment. (Gor, 2006)
Specifically for females, the T. vaginalis infection may occur when the normal acidity of the vagina changes from a healthy and semi-acidic pH to a more basic pH of 5 to 6. This organism could also survive for a maximum of 24 hours in urine, semen or water samples. Considered as one of the most durable protozoan trophozites, the T. vaginalis has the ability to persist on fomites with a moist surface for one to two hours (Talaro, 2002).
As mentioned, the T. vaginalis mainly infect vaginal epithelium. Aside from this, it may also infect the endocervix, urethra and Bartholin and Skene glands. (Gor, 2006)
Prevalence and Risk Factors
In the United States (US), the actual frequency of vaginitis caused by T. vaginalis is difficult to ascertain. According to research, it affects all races and age groups. Highest incidence is noted among African American, wherein occurrence may range from 1.5 to nearly 4 times greater than other racial or ethnic groups (Sorvillo, 2001). On the other hand, lowest incidence is in Asians. In terms of age, high incidence is observed among young, sexually active women. (Gor,