[Assessment of nucleic acid testing (NAT) for screening hepatitis B in blood donors. Systematic review]

The new techniques of molecular biology called "nucleic acid testing" (NAT), enable the detection of particles of viral DNA in hepatitis B, regardless of the disease stage. These NAT techniques increase the sensitivity of screening, so the risk of infection through transfusion could be reduced. The aim of the study was to assess NAT techniques for screening hepatitis B in blood donors. We carried out a systematic review in Medline and Embase databases (2000-2008), as well as INAHTA, Cochrane Library and EuroScan. MeSH terms used were "Hepatitis B", "Blood Transfusion", "Blood Donors", and "Nucleic Acid Amplification Techniques", and free terms as "hepatitis B", "hbv", "nat", "nat-hbv" and "nucleic acid amplification testing". Twelve studies were included, four of them used self-made PCRs, obtaining mixed results, three used Procleix (two samples identified by NAT were HBsAg (-), 0.05% and 0.013%; and the third study with 135 patients who received anti-HBV therapy and had HBsAg (-), showed 80% of positive samples by NAT techniques). Four papers about MPX reported percentages ranging between 0.083 and 0.0015. In the study of diagnostic tests including the two techniques, they showed the same sensitivity. Both NAT techniques, have a good capacity for screening hepatitis B and showed similar results in sensitivity. They may be a significant advance in automation of blood banks and increase the safety of transfused patients.