:Trichomonas vaginalis

L5:Trichomonas vaginalis
Trophozoites

Although typical Trichomonas vaginalis trophozoites may reach up to 30 ?m in length the average length, is 8 to 15 ?m long. The trophozoites may appear ovoid, round, or pearlike in shape. Rapid, jerky motility is accomplished with the aid of the organism’s four to six flagella, all of which originate from the anterior end. Only one of the flagella extends posteriorly. The flagella may be difficult to find on specimen preparations. The characteristic undulating membrane is short, relatively speaking extending only one half of the body length. The single nucleus is ovoid, nondescript, and not visible in unstained preparations. Trichomonas vaginalis trophozoites are equipped with an easily recognizable axostyle. That often curves around the nucleus and extends posteriorly beyond the body. Granules may be seen along the axostyle. Fig. ( ) .








Table (10) : Trichomonas vaginalis trophozoite : Typical characteristics
Size range Up to 30 ?m long
Shape Oval or round to pear
Motility Rapid , jerky
Nuclei One, ovoid
Flagella All originating anteriorly :
Three to five extending anteriorly
One extending posteriorly
Other features Undulating membrane extending half of body length
Prominent axostyle common



Cyst

There is no known Trichomonas vaginalis cyst stage.

Life cycle
Trichomonas vaginalis trophzoites reside on the mucosal surface of the vagina in infected women. The growing trophozoites multiply by lonitudinal binary fission and feed on local bacteria and leukocytes. The Trichomonas vaginalis trophozoites thrive in a sligtly alkaline or slightly acid PH environment, such as that commonly seen in an unhealthy vagina. The most common infection site of T. vaginalis in males is the prostate gland region and the epithelium of the urethra. The detailed life cycle in the male host is unknown.

Clinical symptoms

Trichomoniasis a vaginal infection caused by the microorganism Trichomonas vaginalis, marked by itching, burning, and frothy, pale yellow to green, bad-smelling vaginal discharge. With long-term infection all symptoms may disappear, although the organisms are still present. In men, infection is usually without symptoms but may be shown by a continuing or recurrent irritation of the urethra. Infection is carried by sexual intercourse, rarely by moist washcloths, or, in newborns, by passage through the birth canal. Diagnosis is by microscopic examination of fresh substances released through the vagina. Treatment is by metronidazole given by mouth. Reinfection is common if sexual partners are not treated at the same time.

Laboratory diagnosis

Trichomonas vaginalis trophozoites may be recovered utilizing standard processing methods in spun urine, vaginal discharges, uretheral discharges and prostatic secretions. Although permanent stains may be performed, examination of saline wet preparations is preferred in many instances.