New Concepts in the Diagnosis and Pathogenesis of Trichomonas vaginalis

Abstract

Trichomonas vaginalis infection is the most commonly encountered sexually transmitted disease. There is a need for more accurate and rapid laboratory diagnostic methods, leading to better control and treatment strategies. Various virulence factors such as adherence, contact-independent factors, hemolysis and acquisition of host macromolecules have been shown to play a role in the pathogenesis of this infection. Detection of the factors that are only present in the pathogenic isolates of trichomonads will lead to a better understanding of the epidemiology of this pathogen. Culture technique is highly specific compared with microscopic techniques, but it is time consuming. Immunological techniques lack proper correlation with clinical manifestations. The application of monoclonal antibodies, either singly or in a group that recognizes a common antigen, along with methods such as detection of common DNA fragment from clinical specimens, may have a promising future in the laboratory diagnosis of trichomoniasis.

A review on Trichomonas vaginalis infections in women from Africa

“…Wet mount microscopy is the first method to be used for the diagnosis of trichomoniasis, and it remains the most frequently used method. 48,49 Wet mount examination requires a minimal protozoal concentration of 10 4 organisms/mL. 49,50 The sensitivity of wet mount microscopy is between 35% and 80%, 17,48,49,50 and it is influenced by the experience of the observer, the presence and the concentration of viable and motile trichomonads in the specimen and the period of transportation of the specimen to the laboratory.…”

“…48,49 Wet mount examination requires a minimal protozoal concentration of 10 4 organisms/mL. 49,50 The sensitivity of wet mount microscopy is between 35% and 80%, 17,48,49,50 and it is influenced by the experience of the observer, the presence and the concentration of viable and motile trichomonads in the specimen and the period of transportation of the specimen to the laboratory. 49,50 Wet mount is the simplest and an inexpensive diagnostic test.…”

“…49,50 The sensitivity of wet mount microscopy is between 35% and 80%, 17,48,49,50 and it is influenced by the experience of the observer, the presence and the concentration of viable and motile trichomonads in the specimen and the period of transportation of the specimen to the laboratory. 49,50 Wet mount is the simplest and an inexpensive diagnostic test. 10,17,48,50 However, it is associated with under-diagnosis of the disease because of the low sensitivity 10,50 and the specimens should be examined immediately after collection because T. vaginalis is unstable in conditions outside the body.…”

“…17,48,50,51 However, these techniques are associated with a loss of motility and morphologic characteristics during the fixation and staining steps. 17,49,50 Furthermore, it is difficult to interpret the stained smears because T. vaginalis can resemble polymorphonuclear leucocytes. 17,49 Papanicolaou (Pap) smear has a sensitivity of ~60% 13,52 but a specificity of 95%.…”

“…17,49,50 Furthermore, it is difficult to interpret the stained smears because T. vaginalis can resemble polymorphonuclear leucocytes. 17,49 Papanicolaou (Pap) smear has a sensitivity of ~60% 13,52 but a specificity of 95%. 52 Moreover, this technique is associated with falsepositive and false-negative results.…”