1. “There’s a resident, do we crossmatch for an A1?”
Brian Adkins, M.D.
7/15/16

2. Story Presented Patient has an A1 antibody
Tech is alerted by Soft to perform crossmatch
Question comes to resident

3. Literature review A1 A2 differ in quantity as well as quality
Fewer A antigens on A2
A2 allele has single amino acid change most commonly leading to extra residues at COOH end
1-8% of A2 individuals develop A1 antibodies ~30% A2B individuals
Anti-A1 does not typically cause hemolytic reactions
Hemolysis and organ rejection have been described
Crossmatch compatible units of A2 or O should be transfused
Shaz et al. 2013

4. The Whole Story A Rh positive patient DAT positive (IgG 2+, C3d 1+)
Anti A1 in the eluate only
Plasma screen is negative
What’s happening?

5. Passive Antibody Transfer
Patient received out of group platelets at outside institution
2 O Rh positive platelets at Cookeville Regional Medical Center on 6/30/16
History of antibody requires crossmatch compatible blood in Soft

6. Transfusion of Incompatible Plasma
Most often occurs in out of group platelets
Most commonly group O to a group A recipient
Apheresis platelets contain ~200 ml of plasma
Rarely associated with non group O platelets
Leads to a positive DAT
Rarely associated with overt hemolysis
Prevention
ABO-compatible products
Washed platelets
Shaz et al. 2013
Yuan 2011

7. Bibliography
Shaz, Beth, Christopher D. Hillyer, Charles Samuel Abrams, and Mikhail Roshal. Transfusion Medicine and Hemostasis: Clinical and Laboratory Aspects. N.p.: n.p., n.d. Print.
Yuan, Shan. "PLATELET PRODUCTS." (n.d.): n. pag. 23 Feb Web.