Article Text
Abstract
Background Studies have shown high rates of concurrent rectal CT in women with urogenital infection. Extra-genital STI testing in women is is not routine, and would be cost-prohibitive for all women. Pooling of samples from different anatomical sites is an effective method of testing for bacterial STIs, however is most commonly used in men who have sex with men. Before implementing pooled sampling within our services we performed a small validation comparing triple site sampling with pooled sampling for detection of CT and Neisseria gonorrhoea (NG) in women <25 years.
Methods This validation was performed at a level 3 genito-urinary medicine clinic in London from January – March 2018. Patients were both symptomatic and asymptomatic. Samples were taken by either clinician or patient. All samples were tested using Aptima Combo 2 nucleic acid amplification tests.
Results 99 cisgender women were included with a median age of 22. 56 women (57%) had symptoms that could indicate an acute STI. None reported rectal symptoms 19 patients tested positive for CT at any site (19% prevalence). Genital only (2) rectal only (7) pharynx only (1) genital + rectal (6) triple site (3). Pooled sampling detected CT RNA in 18/19 patients (95%) and was equivocal in 1/19 patients (sensitivity 95% specificity 100%).
Conclusion We demonstrated high prevalence of extra-genital CT infection in women. 2/19 had genital infection alone; genital sampling would miss 8/19 (42%) of CT infection. In this small evaluation, pooled sampling has been shown to be sensitive and specific for detection of CT. 16/19 women (84%) had rectal CT. Our study is limited by size and inconsistent documentation of receptive anal sex, however evidence shows this to be a poor predictor of rectal CT infection. We limited our sample to a high prevalence population so our results may not be generalizable to lower prevalence groups.
Disclosure No significant relationships.