Essential IgG cryoglobulinemia with purpura and cold urticaria.

An 80-year-old woman with essential cryoglobulinemia developed recurrent, widespread, purpuric lesions with superficial skin ulcers and cold urticaria. No disorders of other organ systems were recognized. Attempts to transfer the cold sensitivity passively by serum and isolated cryoprecipitate of the patient were successful. Immunochemical studies showed that the cryoglobulin was composed of IgG only. It was suggested that the cryoprecipitate might not be due to immune complex formation in this case.