Make the Diagnosis: Sickle Cell Stumper


Case Findings: A 26-year-old African American female with sickle cell anemia presents to the hospital with chest pain and shortness of breath. She has been transfused 3 units of packed red blood cells within the last 3 months at another institution. Preliminary testing in the blood bank indicate the following: ABO/Rh: A Rh-positive, Direct antiglobulin test: positive; IgG, and antibody screening test shows Cell I IAT: 2+, Cell II IAT: 3+, Cell III IAT: 2+. The initial antibody panel is done. The blood bank technician performs an alloadsorption to look for any underlying alloantibodies (Image B).

What is your diagnosis after reviewing the images?

70% Anti-E and Anti-Jkb

141% Anti-E, Anti-Jkb, and Warm autoantibody

49% Anti-Fyb, Anti-Leb

159% Anti-Fyb, Anti-Leb, and Warm autoantibody

151% Warm autoantibody


Correct Answer:

B. Anti-E, Anti-Jkb, and Warm autoantibody. Up to 30% of patients with RBC autoantibodies also have underlying alloantibodies. Some centers phenotype or genotype patients with autoantibodies and provide phenotypically matched RBCs. Alternatively, one may perform adsorption tests to detect potential alloantibodies. In this case, an alloadsorption was performed because the patient was recently transfused, preventing an autoadsorption. Instead, panel RBCs with known antigen specificity can be used to rule out the majority of clinically significant antibodies. If the patient’s RBC phenotype is not known (as in this case), then 3 different RBC phenotypes: R1R1, R2R2, and rr could be used in order to have RBCs of complementary phenotypes. (For example, one set of adsorbing RBCs should lack Jka, and another should lack Jkb).

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