Prevention of posttransfusion hepatitis B and C by screening for antibody to hepatitis C virus and antibody to HBcAg.

Screening of blood donors by testing for antibody to HBcAg and antibody to hepatitis C virus is commonly done. However, the applicability of these screening tests may vary depending on the prevalence of hepatitis B virus and hepatitis C virus infection in various populations. We have therefore prospectively evaluated 158 adult patients who received blood or blood products during open-heart surgery in Hong Kong to compare the efficacy of various serological screening tests in the prevention of posttransfusion hepatitis. Serum from five (0.5%) donors was positive for antibody to hepatitis C virus by second-generation enzyme immunoassay; in two, optical-density readings in enzyme immunoassay were greater than 2.0, but only one was positive for hepatitis C virus RNA by reverse transcription-polymerase chain reaction. The latter donor was also positive for antibody to HBcAg and had elevated serum ALT activity. The recipient of a unit of this donor's blood was the only one in whom posttransfusion hepatitis C developed (0.1% per unit transfused). Screening with antibody to hepatitis C virus was more specific than that with antibody to HBcAg or ALT in excluding donors from transmitting hepatitis C (99.6%, 79.4% and 98.8%, respectively). Both the sensitivity and negative predictive value of screening for antibody to hepatitis C virus were 100%, but the positive predictive value was only 20%. Forty-five blood recipients were considered susceptible to hepatitis B virus infection because testing for hepatitis B serology in serum (HBsAg, antibody to HBsAg and antibody to HBcAg) was negative before being transfused. Asymptomatic hepatitis B seroconversion developed in three (6.7%) recipients (1.1% per unit transfused).(ABSTRACT TRUNCATED AT 250 WORDS)