Use of home-based self-collected dried blood spots to test for syphilis, HIV, hepatitis C and B virus infections and measuring creatinine concentration

Abstract

Abstract Introduction Home-based self-collected dried blood spot (DBS) sampling could simplify sexual health and pre-exposure prophylaxis (PrEP) care and reduce sexually transmitted infections (STI) clinic visits for men who have sex with men (MSM). We compared the performance of DBS to venipuncture collected blood samples to test four STIs and creatinine concentration. Methods We invited MSM clients of the Amsterdam STI clinic to participate. Routinely collected peripheral blood was tested for syphilis treponemal antibody (CLIA), HIV (HIV Ag/Ab), HCV (antibodies), HBV (HBsAg) and creatinine concentration. Participants received a home kit for DBS sampling, a return envelope and a questionnaire to evaluate the acceptability, feasibility and usability of DBS, measured on 5-point Likert scales, 1 representing complete disagreement and 5 complete agreement. We assessed sensitivity and specificity of DBS versus peripheral blood-based testing. Results In 2020-21 we included 410 participants; 211 (51.5%) returned a completed DBS card, 117 (28.5%) returned a partially filled card and 82 (20%) did not return a card. The sensitivity for syphilis was 90.8% and the specificity 84.3%. For both HIV Ag/Ab and HBsAg the sensitivity and specificity were 100.0%. The sensitivity for HCV antibody was 80.0% and the specificity 99.2%. The DBS creatinine concentration was a mean of 5.3 μmol/L higher than in venipuncture obtained plasma. Participants’ median willingness to take a future DBS was 4 [IQR 3 – 5]. Discussion DBS may be an acceptable method among MSM for STI testing and creatinine follow-up during PrEP use. However collecting enough blood on DBS cards was a challenge, and sensitivities for syphilis and HCV serology were too low.