Cryoglobulin may be present in the blood of patients who apparently do not have any significant or evident disease, the condition being known as "essential cryoglobulinemia," or it may be present in the blood of patients who have a great variety of diseases when it is recognized as "symptomatic cryoglobulinemia."
The purpose of this report is to review briefly some of the pertinent medical literature concerning cryoglobulinemia, with special emphasis on the dermatologic findings which have been reported, and to present the histories of two patients with essential cryoglobulinemia.
REVIEW OF LITERATURE
Stein and Wertheimer,* in 1942, and later in 1944,3 designated the term "cold fraction," or cold-susceptible portion, as the protein portion of a serum which precipitated when the serum stood for 24 hours at 7 to 11 C. With warming of the serum to 37 C the protein tended to revert to a dissolved