Cryoglobulinemia with a Digital Gangrene from Monoclonal Gammopathy of Undetermined Significance

Abstract

Type I cryoglobulin is composed of a monoclonal immunoglobulin (Ig) and can be found in patients with lymphoproliferative disorders. Some frequent symptoms of type I cryoglobulinemia are skin necrosis and Raynaud’s phenomenon [1]. Monoclonal gammopathy of undetermined significance (MGUS) is a precursor lesion for multiple myeloma [2] and one of the principal causes of cryoglobulinemia [3]. A 37 year-old-male was admitted with gangrene of the left second toe (Figure 1). The patient was diagnosed with primary Raynaud’s syndrome at a tertiary center and has been under observation without treatment for 3 years. Concerning the complete blood count, the white blood cell count was 9,920/μL and the differential was normal. Hemoglobin was 11.5 g/dL; and the platelet count was 361,000/μL. Erythrocyte sedimentation rate was 120 mm/h. Total protein was 10.1 g/dL; and albumin was 3.4 g/dL with a reversed albumin/globulin ratio of 0.5. Serum creatinine was 1.2 mg/dL; and the total calcium was 8.7 mg/dL. The rheumatoid factor was 17 IU/mL; and the antinuclear antibody test was positive but was in a low titer of 1:40. The test for anti-neutrophil cytoplasmic antibody was negative; and both IgG and IgM anticardiolipin antibodies were negative, and the lupus anticoagulant was also negative. However, cryoglobulin came out as positive. Furthermore, a peripheral blood smear showed marked rouleaux formation and numerous