Abstract
Cold agglutinin disease (CAD) is a rare condition that typically presents with a combination of extravascular hemolysis, which is caused by immunoglobulin M binding to the RBC membrane, and cold-induced symptoms such as Raynaud’s phenomenon due to agglutination of red blood cells (RBC) under temperatures of around 3 to 4 °C. We report a case of CAD that was initially diagnosed as mechanical hemolysis and alcoholic liver disease. It took 25 days to diagnose CAD despite the patient presenting with the typical combination of hemolytic anemia and Raynaud’s phenomenon. We believe that our experience offers the following three lessons for primary care physicians:1 ) Physicians must recognize CAD as a rare but important cause of the combination of Raynaud’s phenomenon and hemolysis. 2 ) Physicians must differentiate hemolytic disorders from mechanical hemolysis through the evaluation of reticulocytes, haptoglobin, and Coombs’ test, even when mechanical hemolysis is highly suspected. 3 ) When encountering new or unexpected combinations of symptoms, physicians must be open to a broad range of possible diagnoses and avoid a tendency toward availability bias.
