A retrospective analysis of false-positive infectious screening results in blood donors.
BACKGROUND
False-positive infectious transfusion screening results remain a challenge with continued loss of both donors and blood products. We sought to identify associations between donor demographic characteristics (age, race, sex, education, first-time donor status) and testing false positive for viruses during routine blood donation screening. In addition the study assessed the prevalence of high-risk behaviors in false-positive donors.


METHODS
Blood Systems, Inc. donors with allogeneic donations between January 1, 2011, and December 31, 2012, were compared in a case-control study. Those with a false-positive donation for one of four viruses (human immunodeficiency virus [HIV], human T-lymphotropic virus [HTLV], hepatitis B virus [HBV], and hepatitis C virus [HCV]) were included as cases. Those with negative test results were controls. For a subset of cases, infectious risk factors were evaluated.


RESULTS
Black race and Hispanic ethnicity were associated with HCV and HTLV false-positive results. Male sex and lower education were associated with HCV false positivity, and age 25 to 44 was associated with HTLV false positivity. First-time donors were more likely to be HCV false positive although less likely to be HBV and HTLV false positive. No significant associations between donor demographics and HIV false positivity were observed. A questionnaire for false-positive donors showed low levels of high-risk behaviors.


CONCLUSIONS
Demographic associations with HCV and HTLV false-positive results overlap with those of true infection. While true infection is unlikely given current testing algorithms and risk factor evaluation, the findings suggest nonrandom association. Further investigation into biologic mechanisms is warranted.
School of Public Health, University of California at Berkeley, Berkeley, California.
Michelle T
MT
Vo
Blood Systems Research Institute.
Roberta
http://orcid.org/0000-0002-5898-8168
R
Bruhn
Blood Systems Research Institute.
Zhanna
Z
Kaidarova
Blood Systems Research Institute.|University of California at San Francisco, San Francisco, California.
Brian S
BS
Custer
Blood Systems Research Institute.|University of California at San Francisco, San Francisco, California.
Edward L
EL
Murphy
Blood Systems Research Institute.|University of California at San Francisco, San Francisco, California.
Evan M
EM
Bloch
D000293:Adolescent; D000328:Adult; D001741:Black or African American; D000367:Age Factors; D000368:Aged; D001782:Blood Donors; D046148:Donor Selection / Q000379:methods*; D005189:False Positive Reactions; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D014777:Virus Diseases / Q000097:blood*; D014780:Viruses