BIOLOGICAL MEANING OF HEPATITIS B VIRUS MARKERS (HBV) IN BLOOD DONORS: ISOLATED Anti-HBc AND ISOLATED HBsAg.

Abstract

INTRODUCTION: The introduction of nucleic acid (NAT) assays for DNA / HBV detection in the routines of public blood banks is recent and there are still few studies in Brazil about them. These methods are highly sensitive and are able to identify donations in the immunological window period and Occult hepatitis B Infection (OBI). At Fundação Pró-Sangue / Hemocentro in São Paulo (FPS-SP), about 130,000 blood donors per year are submitted to serological tests (HBV, HCV, HIV, Chagas disease, Syphilis and HTLV) and NAT in minipools of 6 (MP-NAT) for the detection of genetic material (HIV, HCV and HBV). Approximately 2% of the blood donations are discarded due some reagent result and, according to the current legislation, the diagnostic confirmation of the altered markers is not required. The number of FPS-SP donations with altered serological and / or molecular profile for HBV is on average 800 donations per year and determining the actual number of cases of the infection can generate very important information to assist in the prevention and dissemination of this virus. Our study aims to determine the cases with infectious potential among the samples that presented one or more reactivity for the HBV markers of FPS-SP donor screening tests (anti-HBc, HBsAg and MP-NAT-HBV) and to classify them in the different Categories of HBV infection (acute, chronic, OBI and immunological window). This study may also assess the value or actual need to perform the three mandatory tests for HBV screening in blood donor screening, especially if there is redundancy of results and cost implications. Thus, it is possible to verify whether the use of a single high-sensitivity NAT in blood donor screening can improve the ability to detect asymptomatic donors and increase transfusion safety.METHODS: Retrospective study with a sampling from the FPS-SP database from May 2016 to May 2017. Reagent samples for one or more HBV markers performed in the routine serological screening (HBsAg, Anti-HBc and NAT-HBV in 6-sample minipool) in the donation sample will be separated. Plasmas stored at -20º C in the Serology Division of FPS-SP will be submitted to nucleic acid extraction and real-time PCR with high sensitivity (10-20 IU / mL) in an individual sample for DNA- HBV detection. (AU)