Detection of red blood cell antibodies in mitogen-stimulated cultures from patients with hereditary spherocytosis

BACKGROUND: Hereditary spherocytosis (HS) is a congenital hemolytic anemia caused by defects in red blood cell (RBC) membrane proteins leading to premature RBC clearance in the spleen. The presence of RBC autoantibodies has never been extensively investigated in HS. STUDY DESIGN AND METHODS: RBC antibody-bound immunoglobulin (Ig)G was investigated in 91 consecutive HS patients by mitogen-stimulated direct antiglobulin test (MS-DAT), a sensitive method able to magnify latent RBC antibody autoimmunity and related with hemolytic variables, previous splenectomy, and type of membrane defect. RESULTS: A total of 61% of HS cases had RBC antibodies by MS-DAT (29 Band 3, 17 spectrin deficiency, and nine no defined defect). The amount of RBC-bound IgG was greater in HS compared with controls (236\ub1192 ng/mL vs. 52\ub129 ng/mL, p<0.0001), although lower than that observed in autoimmune hemolytic anemia (AIHA; 634\ub1371 ng/mL vs. 236\ub1192 ng/mL, p