Definition & types (Lancet 2012;379:348; Oncology 2013;37:1098)

  • Cryoglobulins: proteins that precipitate from serum or plasma on exposure to cold and redissolve on rewarming, characterized by their composition; a/w chronic immune stimulation and/or lymphoproliferation
  • Distinguish from cryofibrinogenemia = proteins (eg, fibrin, fibrinogen) that precipitate only from plasma; found in autoimmune dis, malignancies, infxns; unclear clinical significance
Types of Cryoglobulinemia
Feature Type I (monoclonal) Type II (mixed) Type III (mixed)
Frequency 10–15% 50–60% 25–30%
Cryoglobulin composition Monoclonal Ig (usually IgM or IgG) Monoclonal IgM w/ RF activity + polyclonal