Type I Cryoglobulinemia Presenting as Hemorrhagic Crusted Leg Ulcers

Cryoglobulins (CGs) are serum proteins that reversibly precipitate when the serum is cooled below 37°C. Cryoglobulinemias are associated with a variety of diseases, including hematologic, autoimmune, and infectious. Isolation of CGs requires handling the specimen with extreme care. We describe a 70-year-old man, recently diagnosed with chronic lymphocytic leukemia, who developed hemorrhagic crusted skin ulcers on his legs that were pruritic and painful. Results of skin biopsies showed dilated superficial, mid-dermal and deep-dermal blood vessels containing pink amorphous material and red blood cells. Cryoglobulinemia was suspected; however, an initial search for CGs was negative. There was concern about suboptimal handling of the specimen, and the test was repeated. Two percent CGs with IgM κ specificity were detected. This case illustrates the importance of the proper handling of specimens for evaluation of cryoglobulinemia.