Infectious Disease, HLA and ABO Donor Qualification Testing









Other Testing
Every unit of blood is tested to identify the donor's blood group (O, A, B or AB) and Rh type, and screened for atypical or unusual red cell antibodies.
Cytomegalovirus (CMV) Antibody Testing (implemented prior to 1985)
The current interventions for high-risk blood recipients who are at increased risk of CMV infection include leukoreduction and CMV antibody testing, neither of which has the capability of detecting free virus in plasma during the acute phase of infection when transmission risk is most likely to be present (i.e., the window period). However, little to no breakthrough CMV infection via transfusion has been documented since the implementation of universal leukoreduction, and hospitals both internationally and in the United States have dropped, and continue to drop, their requirements for CMV seronegative labeled blood with the use of universal leukoreduction. The major risk of CMV infection in low and very low birth weight infants (the major risk group) is from breast milk from infected mothers. The current risk of CMV transfusion transmission remains theoretical; such risk from the CMV DNA window period is undocumented and unknown.
CMV antibody testing is performed on a portion of blood donations, including all platelet donations, to meet hospital demand for CMV "safe" (seronegative) blood products. Antibody testing may be requested in addition to universal leukoreduction as intended for specific vulnerable patient populations. CMV-seronegative donations are labeled as negative.
Human Leukocyte Antigens (HLA) Antibody Testing (implemented in 2016)
HLA testing is performed on donations from female donors who indicate they have ever been pregnant (first-time donors) or donors who have had a pregnancy since their prior HLA-negative donation (repeat donors) as a mitigation for HLA-antibody-mediated Transfusion-Related Acute Lung Injury (TRALI). Donors who test HLA reactive by the FDA-licensed screening test for HLA class I and II antibodies are further tested to determine their ongoing suitability via Luminex using a validated cutoff for donor screening. Donors testing negative in duplicate can be reinstated..