Seven Years Experience in NAT Testing of Blood Donors in a Tertiary Care Centre

ABSTRACT

Introduction: Nucleic acid amplification testing (NAT) isa very sensitive and specific test for viral nucleic acids.Itreduces the window period for detection of viruses. It is highlybeneficial in countries like India which has a high incidenceand prevelance of transfusion transmitted infections. NATis expected to identify many NAT yield cases which are notdetected by other serological tests.Material and methods: A retrospective analysis oftransfusion transmitted infection (TTI) reactive units in atertiary care hospital was done over a period of seven yearsfrom Jan 2011 to Dec 2018. The blood units were tested byenhanced chemiluminesense technology and Individual donornucleic acid testing (ID- NAT). NAT yield was calculated forHepatitis B, C and HIV.Results: Out of 23,378 collected blood units, 380 units(1.62%) were found to be reactive for one or more transfusiontransmitted viruses by chemilumunisense and/or NAT. 371units (1.58%) were found reactive by chemiluminesense and190 units (0.81%) by NAT. All the NAT yield cases were forhepatitis B virus and it was 9 (12597).Conclusion: NAT is more sensitive than chemiluminisense indetection of Hepatitis B. It detects both window period andoccult infection.It has made a significant contribution towardsensuring safe blood transfusion by helping in reduction ofwindow period transmission of Hepatitis B. It is important toimplement NAT in developing countries like India to enhancetransfusion safety.