Complement-Mediated Autoimmune Hemolytic Anemia as the Initial Presentation of Renal Cell Carcinoma: A Case Report

Abstract

Autoimmune hemolytic anemia (AIHA) is a rare hematological disorder that may occur as a primary condition or secondary to underlying diseases including malignancies. Although AIHA is commonly associated with lymphoproliferative disorders, association with solid tumors such as renal cell carcinoma (RCC) remains uncommon. We report a 67-year-old gentleman who presented with symptomatic anemia and laboratory evidence of complement-mediated hemolysis. Direct antiglobulin testing demonstrated anti-IgG positivity and strong C3d positivity suggestive of complement-mediated AIHA. Clinical examination revealed a ballotable left-sided abdominal mass. Imaging demonstrated a left renal mass with central necrosis and para-aortic lymphadenopathy highly suggestive of RCC. The patient demonstrated favorable hematological response following corticosteroid therapy and transfusion support. This case highlights the importance of evaluating for underlying malignancy in patients presenting with unexplained hemolysis.