Price, Collin M.Peters, Remco P.H.Steyn, JanréMudau, MaandaOlivier, DawieDe Vos, LindseyMorikawa, ErikaKock, Marleen M.Medina-Marino, AndrewKlausner, Jeffrey D.2018-06-052018-05Price, C.M., Peters, R.P.H., Steyn, J. et al. 2018, 'Prevalence and detection of Trichomonas vaginalis in HIV-infected pregnant women', Sexually Transmitted Diseases, vol. 45, no. 5, pp. 332-336.0148-5717 (print)1537-4521 (online)10.1097/OLQ.0000000000000756http://hdl.handle.net/2263/65100BACKGROUND : Trichomonas vaginalis is a sexually transmitted infection associated with increased transmission of HIV and significant adverse birth outcomes; culture and polymerase chain reaction (PCR) are commonly used in diagnosis. METHODS : Consenting HIV-infected pregnant women were recruited from clinics in South Africa and screened for T. vaginalis using PCR. Polymerase chain reaction-positive women provided an additional sample for culture. We compared T. vaginalis detection between PCR and culture, and investigated how PCR cycle threshold (Ct) values differ among culture results. RESULTS : A total of 359 women were enrolled and 76 (20%) tested T. vaginalis PCR positive. Cultures were obtained from 61 of the PCR-positive women, and 38 (62%) were culture positive. The median baseline Ct of the PCR-positive/culture-positive group was 22.6 versus 38.0 among those who were PCR positive/culture negative (P < 0.001). Culture-positive cases had lower Ct values (higher DNA load); a Ct value less than 30 predicted positivity with a sensitivity of 97% and a specificity of 96%. CONCLUSIONS : Culture was positive in roughly half of PCR-positive cases. The culture-negative cases had significantly higher Ct values, indicating a lower concentration of T. vaginalis DNA. A Ct value of 30 provides a reliable threshold for predicting culture positivity. The clinical significance of culture-negative infections detected by PCR is still unclear.en© 2017 American Sexually Transmitted Diseases Association All rights reserved. This is a non-final version of an article published in final form in Sexually Transmitted Diseases, vol. 45, no. 5, pp. 332-336, 2018. doi : 10.1097/OLQ.0000000000000756.Trichomonas vaginalisSexually transmitted infection (STI)Human immunodeficiency virus (HIV)Birth outcomesCulturePolymerase chain reaction (PCR)PregnancyLow birth weight (LBW)Risk factorsPostprint Article