• Thompson, R. C. A.
• Asmah, R. H.
• Squire, D. S.
• Ahmed, H.

Abstract

Trichomonas vaginalis is the causative agent for the most prevalent nonviral sexually transmitted infection (STI) among women and the infection is associated with varied clinical presentations and outcomes. We conducted a cross-sectional study on 479 women visiting gynaecological and STI clinics in Southern Ghana between January and April 2016 to assess the risk factors associated with T. vaginalis and clinically characterize the infected groups. Vaginal samples were analysed using wet preparation microscopy and polymerase chain reaction (PCR). Of the 479 women, 63 (13.2%; 95% CI 9.5-17.6) and 78 (16.8%; 95% CI 12.2-21.1) had T. vaginalis infection based on wet preparation and PCR respectively, and diagnosis by PCR was significantly more sensitive (P < 0.0001). Univariate analyses found that Trichomonas vaginalis infection was significantly associated with vaginal itch (OR = 1.38, P = 0.04), oral sex (OR = 1.10, P = 0.04) and a prior history of stillbirth (OR = 3.62, P = 0.04). We used a model averaging approach to examine the relationship between T. vaginalis infection and predictor variables for clinical signs and risk factors. Vaginal itch was ranked highest in variable importance for clinical signs, occurring in 62% of the top eight models; discharge colour and discharge consistency were other variables also occurring in the top set of models. Scores were assigned based on the presenting clinical signs to categorise the pathogenicity levels of T. vaginalis into four groups; 6 (6.7%) corresponded to non-pathogenic group, 21 (23.6%) to the very low pathogenic, 39 (43.8%) to the low pathogenic and 12 (13.5%) to the high pathogenic group. A history of engaging in oral sex was ranked highest in variable importance for risk factors, occurring in 72% of the top-ranked models; cleaning material used after toileting and educational level also appeared in more than 50% of the top-ranked models. The varied clinically characterized groups suggest the existence of genetic polymorphism in the T. vaginalis infecting these individuals.

Topics

• impedance spectroscopy
• chemical ionisation
• microscopy