Cold Agglutinin Syndrome as the Initial Presentation of Acute Myeloid Leukemia: A Case Report

Cold agglutinin‐mediated autoimmune hemolytic anemia, when secondary to viral and bacterial infections or, rarely, malignancy, is called cold agglutinin syndrome. This is the first case in which acute myeloid leukemia (AML) was the underlying cause of this syndrome. Here, we present a 64‐year‐old man with weight loss, jaundice, anemia, and a recent episode of red urine. The blood drawn from the patient clotted swiftly, and then the cold agglutinin test became positive. Bone marrow specimen microscopy revealed monocytic AML. Standard treatment resulted in clinical improvement, although he later faced progression to hyperleukocytosis and liver failure, which led to his death. This case emphasizes the necessity of maintaining a level of suspicion for underlying hematologic malignancies in individuals with secondary cold agglutinin‐mediated hemolytic anemia. This is the first documented case of cold agglutinin syndrome related to AML, contributing to the growing knowledge of the connection between autoimmune hemolytic anemia and hematologic cancers.