Warm autoantibodies: time for a change

Routine adsorption procedures to remove autoantibodies from patients’ serum often require many hours to perform. This time-consuming process can create significant delays that affect patient care. This study modified the current adsorption method to reduce total adsorption time to 1 hour. A ratio of one part serum to three parts red blood cells (RBCs; 1:3 method) was maintained for all samples. The one part serum was split into three tubes. Each of these three aliquots of serum was mixed with one full part RBCs, creating three adsorbing tubes. All tubes were incubated for 1 hour with periodic mixing. Adsorbed serum from the three tubes was harvested, combined, and tested for reactivity. Fifty-eight samples were evaluated using both the current method and the 1:3 method. Forty-eight (83%) samples successfully adsorbed using both methods. Twenty (34.5%) samples contained underlying alloantibodies. The 1:3 method demonstrated the same antibody specificities and strengths in all 20 samples. Eight samples failed to adsorb by either method. The 1:3 method found previously undetected alloantibodies in three samples. Two samples successfully autoadsorbed but failed to alloadsorb by either method. The 1:3 method proved to be efficient and effective for quick removal of autoantibodies while allowing for the detection of underlying alloantibodies. Immunohematology2013;29:5–10.