Small skin blood vessel occlusions by cryoglobulin aggregates in ulcerative lesions in IgM‐IgG cryglobulinemia

Abstract
The skin biopsy specimens from six patients with primary mixed IgM‐IgG cryoglo‐bulinemia were examined by immunofluorescence, light and electron microscopy. The biopsy taken from the involved skin of one patient with leg ulcers revealed small blood vessel occlusions by cryoglobulin aggregates. Since a similar finding was not observed in the biopsy material taken from the other five patients who had no ulcerative skin lesions, it seems that the cryoglobulin aggregates play a role in the development of the skin ulcerations in primary mixed IgM‐IgG cryoglobulinemia.