Role of Anti HB Core Anitbody Screening by Chemiluminescence in Facility with ID-NAT Testing

Authors:

Ranjay Kumar Choudhary (Manav Rachna International University, Faridabad)

Prof. (Dr.) Jaswant Singh (Manav Rachna International University, Faridabad)

Dr. Harprit Singh (Alchemist Health Institute, Gurgaon)

Keywords: ID-NAT: Individual Donor- Nucleic Acid Test, NAT: Nucleic Acid Testing, TTI: Transfusion Transmitted Infection, HBV: Hepatitis B Virus, ELISA: Enzyme Linked Immunosorbent Assay, CLIA: Chemiluminescence Immunoassay, TAHBV: Transfusion associated hepatitis B virus, HBsAg: Hepatitis surface antigen, HCV. Hepatitis C virus, HIV: Human Immunodeficiency Virus, HBcAb: Hepatitis core antibody, DNA: Deoxyribonucleic acid, -ve: Negative, +ve: Positive.

Abstract:

The screening for Anti HBV core antibodies (HBcAB) is employed by various blood centers to decrease the transmission of HBV in case of HBsAg -ve blood. Recently, Nucleic Acid Test (ID- NAT) testing has been adopted for routine screening of blood including HBV in some blood centers. The addition of tests leads to increase in the cost of transfused blood. This study was carried out to look into the possibility of obviating the need of screening of HBV core if a facility of NAT testing exists, so as to optimize the resource utilization. The screening results of donated blood at a tertiary care hospital based blood centers were evaluated from January 2010 to July 2010 covering 2740 samples. Serological screening of donated blood was carried out by random access Chemiluminescence Immuno Assay (CLIA) for TTI including HBsAg & HBcAb — Total). Also, Individual donor NAT (ID- NAT) was performed for HBV. Of the 2740 blood donors, 186(6.7%) were reactive for HBV marker. There was no sample, which was non-reactive by serological markers, observed to be NAT reactive. About 6% of blood was discarded based on HBV core reactive alone. Of all the samples reactive — 16 (8.6%) were true +ve. Total of 4 samples (2.15%) were observed to be reactive for core that was confirmed by ID-NAT. Total of 3 samples (1.61%) were HBsAg Reactive and HBV core non reactive confirmed to be +ve by NAT. HBcAb is the most common cause of discarding blood by TTI Screening. Still, HBcAb should be carried out to rule out transmission of HBV among HBsAg non-reactive blood (2.15%). On contrary, no sample was observed, which was NAT reactive and is not reactive by CLIA. Therefore, the screening for core antibody seems to be a better strategy than NAT in case of resource limitation.