Immunoglobulin A (IgA) levels in blood products and plasma derivatives

Both anaphylactic and anaphylactoid reactions to transfused blood products and plasma derivatives have occurred in IgA-deficient patients with antibodies to IgA. This study reports the concentration of IgA in various blood products to assist in the development of treatment protocols for IgA-deficient patients. Five types of blood products and seven types of plasma derivatives were tested for the presence of IgA using a semiquantitative hemagglutination inhibition method. The concentration of IgA was measured by radial immunodiffusion and enzyme-linked immunosorbent assay techniques. Blood products which consistently contained IgA less than 0.05 mg/dL (the present definition for IgA deficiency used by the American Red Cross Rare Donor Registry) were from IgA-deficient donors, deglycerolized red blood cells (RBCs) prepared with an extra wash cycle, and RBCs washed using a total volume of approximately 1300 mL of 0.9 percent sodium chloride.