Researchers from Japan presented the case of a man, aged 80 years who developed necrosis secondary to cold agglutinin disease (CAD), as published in the Canadian Medical Association Journal. This case highlights the importance of managing the disease in a timely manner to avoid the development of complications.

The patient presented here had gone to the hospital with a 7-month history of purple discoloration, numbness, and pain on the third and fourth fingers of his left hand. His feet and right hand were not affected. He had a history of diabetes but this was well-controlled.

The discoloration was worsened by cold exposure but did not return to normal, which ruled out Raynaud phenomenon, the authors said.

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Based on laboratory tests, the patient was diagnosed with CAD and referred to the hematology department. “To diagnose [CAD], the cold agglutinin titre is at > 64, but usually higher,” wrote first author Hiroaki Nakagawa and the coauthors of the study. This patient’s titer was 1:8192.

A week later, he developed necrosis in his fourth left finger but this healed by keeping warm and avoiding cold exposure. A year later, he had no new lesions or progression of anemia just by avoiding cold exposure.

CAD is caused by the production of autoantibodies called cold agglutinins that mistakenly attack the body’s own erythrocytes causing hemolytic anemia on exposure to temperatures between 32 ºF and 50 ºF. The disease can be primary in which case the reason why the body produces cold agglutinins is not known or secondary where the disease develops following malignant diseases, acute infections, or other autoimmune disorders.

The disease can be managed with cold exposure avoidance including cold foods and drinks. In severe cases, plasmapheresis and treatment with rituximab or sutimlimab may be necessary.


Nakagawa H, Kato C, Miyata Y. Necrosis secondary to cold agglutinin disease. Can Med Assoc J. 2022;194(14):E528. doi:10.1503/cmaj.211570