A Rare Case of IgA-mediated Autoimmune Hemolytic Anemia in a Young Adult

Abstract

A 21-year-old previously healthy male presented with unexplained intravascular hemolysis. Patient had anemia, elevated serum indirect bilirubin, elevated LDH, reticulocytosis, decreased haptoglobin and spherocytosis. Initial Laboratory investigations revealed a negative direct antiglobulin test (DAT), suggesting a Coombs-negative hemolytic anemia. Additional testing with monospecific anti-IgA was strongly positive. Autoimmune hemolytic anemia due to warm-reacting IgA autoantibodies is very rare and presents with "Coombs negative" autoimmune hemolytic anemia. A diagnosis of idiopathic IgA-only-associated warm AIHA was made after extensive investigations. Treatment included transfusion of multiple ABO/RH-D compatible typed red cell concentrates and administration of high-dose steroids. This case report will highlight the initial clinical presentation, panel of investigations for diagnosis; course of treatment and follow up with a brief literature review of the pathophysiologic mechanism and suggested treatment modalities for this rare IgA-induced warm AIHA.