The use of HIV antiretroviral (ARV) as therapy -or prophylaxis by blood donors may compromises the detection ability of HIV blood screening tests and represents a risk for blood transfusion safety. Our objective was to determine the frequency in three years of undeclared ARV use by blood donors with HIV altered markers, starting in 2018 when HIV prophylaxis began in Brazil.

In a retrospective cross-sectional analysis of 345.252 blood donations, 361(0.1%) blood donations were reactive for HIV antibody-antigen in a chemiluminescent immunoassay and/or RNA screening tests. Samples from 296 (81.9%) of these HIV reactive donations were available for ARV testing by high-performance liquid chromatography-tandem mass spectrometry. Confirmatory tests data recorded from donor return were assessed. Additional serological assays and/or RT-PCR were performed on donation samples of non-returned donors.

The frequency of ARV use was 2/83 (2.4%) in HIV confirmed positive donors or 2/5 (40%) in potential elite controller profile donors (HIVAb/Ag-positive and HIV RNA-negative). A single ARV, lamivudine, was found in two donors at low concentrations of 11.3 and 6.7 ng/mL. The entricitabine, efavirenz, darunavir, atazanavir and tenofovir drugs were not detected in none of the 296 donations.

HIV-positive individuals on unreported ARV use are donating blood and their donations jeopardize blood safety. Even though they were directly questioned about use of any medication, HIV ARVs therapy or HIV ARV prophylaxis they were not declaring accurate information in pre-donation questionnaire. We are aware that only a fraction of ARV users have been detected and we know that the greatest concern is for those on ARV prophylaxis use who may not have antibodies or RNA at detectable levels by the methods currently used. In such cases, more sensitive individual nucleic acid tests, as well as PCR that detect proviral HIV DNA in the blood, or pathogen reduction systems, may be needed. Efforts to educate blood donation candidates about the risk of unreported ARV use are needed.