Relationship between antibody to hepatitis B core antigen and retroviral infections in blood from volunteer donors.
BACKGROUND
The value of the test for antibody to hepatitis B core antigen (anti-HBc) as a surrogate screening assay in the time before sensitive, virus-specific screening tests were available has been well established. There is significant debate, however about the residual value of anti-HBc screening after the implementation of human immunodeficiency virus (HIV)-, human T-lymphotrophic virus (HTLV)-, and hepatitis C virus (HCV)-specific assays and, in particular, about its utility as a lifestyle marker to identify persons at risk for retrovirus infections.


METHODS
Screening tests for antibodies to HIV, HTLV, and HBc, as well as confirmatory or supplemental test results for anti-HIV and anti-HTLV, were obtained from approximately 2.8 million donations collected from 1991 through 1993 by five blood centers within the United States. The sensitivity, positive predictive value, and relative prevalence of anti-HBc for each retrovirus were calculated and compared among demographic subgroups.


RESULTS
The overall relationship between anti-HBc and anti-HIV was similar to that between anti-HBc and anti-HTLV. When calculated from the measured endpoint of the prevalence of anti-HIV-positive and anti-HTLV-positive donations, the sensitivities were 31.1 and 26.2 percent, the positive predictive values were 0.18 and 0.21 percent, and the relative prevalences were 30.1 and 23.8, respectively. Among 27 anti-HIV-seroconverting donors and 9 anti-HTLV-seroconverting donors, the sensitivities were 7.4 percent (95% CI: 0.9-24.3%) and 0 percent (95% CI: 0.0-28.3%), respectively. It was estimated that for each HIV-infected window-period donation detected by anti-HBc, from 19,000 to 81,000 HIV-noninfected donations are discarded. Similarly, more than 33,000 HTLV-noninfected donations are likely to be discarded for each HTLV-infected donation detected by anti-HBc.


CONCLUSIONS
Although anti-HBc-reactive donations are more likely to be seropositive for a retrovirus than are anti-HBc-nonreactive donations, the low positive predictive value limits the test's effectiveness. If the anti-HBc test is retained in the blood donor setting, efforts should be focused on reducing the number of false-positive results.
Korelitz
J J
JJ
Westat, Inc., Rockville, Maryland, USA.
Busch
M P
MP
Kleinman
S H
SH
Williams
A E
AE
Zuck
T F
TF
Gilcher
R O
RO
Ownby
H E
HE
Co Chien
H
H
Nemo
G J
GJ
D000293:Adolescent; D000328:Adult; D001782:Blood Donors; D006800:Deltaretrovirus Infections / Q000175:diagnosis*; D005260:Female; D015658:HIV Infections / Q000175:diagnosis*; D018023:HIV Seronegativity; D006679:HIV Seropositivity; D006510:Hepatitis B Antibodies / Q000097:blood*; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens