MICROBIOLOGY

• Trichomonas vaginalis (TV): 5-15 µm, pear-shaped, motile, flagellated protozoan parasite.
  • Exists in the trophozoite stage only [Fig. 1; life cycle].
    • Facultative anaerobe divides by binary fission.
    • Optimal growth in moist milieu at a pH of 4.9-7.5 and a temperature of 35^oC-37^oC.
  • Trichomonads gather in clusters on the stratified urogenital epithelium, covering only a small surface area.
    • Parasites invade the superficial epithelium causing damage directly beneath the clustered trichomonads.
    • The nonspecific inflammatory response was noted in the lamina propria with plasma cells, lymphocytes, and neutrophils present.
    • Superficial ulceration of the epithelium can occur.
• Transmission issues:
  • Can survive up to 45 minutes on clothing, washcloths, and in bathwater.
  • The presence of infection enhances the acquisition of HIV infection.
  • Antecedent bacterial vaginosis (BV), is a risk factor for T. vaginalis acquisition.