Hypersplenism induced by splenic vein ligation.

Warm autoimmune hemolytic anemia (AIHA) is a rare clinical entity. It is usually caused by an IgG autoantibody directed against the red blood cell membrane that causes extravascular hemolysis predominantly in the spleen. As a result, disease states or procedures that result in hypersplenism would be expected to increase red cell destruction in patients with an underlying warm AIHA. We present the case of a patient with a previously undiagnosed warm AIHA, who developed worsening hemolysis after undergoing splenic vein ligation during a pancreaticoduodenectomy to remove a neuroendocrine tumor.