HBV profile of the occult HBV infection in blood donors at Maharaj Nakorn Chiang Mai Hospital

Abstract

Background: Since August 2008, NAT screening of blood donations by Procleic Ultrio test and Cobas TagScreen MPX test for detection of HIV-1 RNA, HCV RNA and HBV DNA has started at Blood Bank Section, Maharaj Nakorn Chiang Mai Hospital, Faculty of Medicine, Chiang Mai University. A total of 118 HBV NAT-reactive hepatitis B surface antigen (HBsAg) negative donors were detected.

Objective: To study the HBV profi le of the HBV DNA reactive donors who were HBsAg negative called occult hepatitis B infection (OBI).

Study Design and Methods: A total of 116,305 HBsAg negative blood donation collected from August 2008 to July 2012 were selected and screened by NAT. All 118 positive HBV DNA was performed for HBV serological markers. There were 73 followed-up blood donors. Determination of HBV DNA and HBV profile were repeated.

Results: Occult hepatitis B infection NAT yield was 1:985 according to 118 positive HBV DNA blood samples. Thirty three (27.96%) donors were negative for all HBV serologic markers and 16 (13.56%) carried both anti-HBc and anti-HBs. Fifty (42.37 %) and 19 (16.10%) samples were reactive for anti-HBc or anti-HBs. The majority of samples (66, 55.93%) showed anti-HBc. Of 118 HBV NAT-yield donors, 73 (61.86 %) were followed-up which found more in male than female. The HBV viral load was lower than 12 IU/ml.

Conclusions: NAT testing in routine blood donor screening can detect HBV DNA in the window period and late stage of infection. It was difficult to detect HBsAg in the low level of HBV DNA blood donors. The decision making for high sensitivity and specificity of the NAT test should be considered for routine testing according to blood transfusion safety. Bull Chiang Mai Assoc Med Sci 2013; 46(1): 72-80