Sensitivity and specificity of Anti-HBc screening assays--which assay is best for blood donor screening?
Compared to HIV and hepatitis C virus, the residual infectious risk of hepatitis B virus (HBV) posed by blood products is about 10 times higher. In addition to HBsAg testing, screening for anti-HBc was recommended by the German Advisory Committee Blood in March 2005. Prevalence of anti-HBc in German blood donors was investigated at five test sites located in different geographic regions. In total, 12,000 blood donors were screened for anti-HBc by PRISM HBcore, and a statistically representative number of these were tested with Abbott Murex anti-HBc total, bioMérieux Hepanostika anti-HBc uniform, Bio-Rad Monolisa anti-HBc PLUS and Dade Behring Enzygnost anti-HBc. Anti-HBc repeat reactive samples were tested for anti-HBs, anti-HBe and HBV DNA by individual donation NAT. The mean prevalence of anti-HBc was 1.75% in donors that had not been tested for anti-HBc in the past. The percentage of anti-HBs in anti-HBc repeat reactive donors was 93.7%. Samples that were additionally reactive for anti-HBe were anti-HBc reactive in all tested assays. The sample to cut-off (S/Co) values for anti-HBc were lower (competitive assays) in samples that were also positive for anti-HBe, when compared to samples that were only anti-HBc reactive. Most commercially available anti-HBc assays provide sufficient sensitivity for routine screening purposes, and lacking specificity is no longer a serious issue for most of them. Assay differences were recognized for samples that were anti-HBc only reactive. The overall loss of 1.75% of positive testing donors can be significantly reduced to 0.45% by implementation of re-entry procedures for donors with an anti-HBs titre of over 100 IU/l and negative by sensitive ID-NAT.
Hourfar
M K
MK
Institute of Transfusion Medicine and Immunohematology, German Red Cross, Johann Wolfgang Goethe University, Frankfurt, Germany.
Walch
L A
LA
Geusendam
G
G
Dengler
T
T
Janetzko
K
K
Gubbe
K
K
Frank
K
K
Karl
A
A
Löhr
M
M
Sireis
W
W
Seifried
E
E
Schmidt
M
M
D001782:Blood Donors; D003140:Communicable Disease Control; D004279:DNA, Viral / Q000097:blood; D046148:Donor Selection; D005858:Germany / Q000453:epidemiology; D006509:Hepatitis B / Q000097:blood / Q000453:epidemiology; D006510:Hepatitis B Antibodies / Q000097:blood; D006512:Hepatitis B Core Antigens / Q000032:analysis / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D012680:Sensitivity and Specificity
D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens