Autoimmune hemolytic anemia (AHAI) is rarely associated with multiple myeloma (MM), may be present at diagnosis or during disease progression, and its pathogenic mechanisms remain unclear. We report the case of a 57-year-old insulin-treated diabetic patient admitted for severe autoimmune hemolytic anemia with warm IgG antibodies. Serum protein electrophoresis revealed a monoclonal IgG lambda protein, urine immunofixation showed a lambda light chain, and the bone marrow was 25% infiltrated with plasma cells. Corticosteroid therapy in combination with treatment for multiple myeloma resulted in remission of the anemia.
Although rare, AHAI should be considered in MM patients with severe anemia and frequent transfusion requirements.