Cryoglobulinemia classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Feham Tariq, MD [2]

Overview

Cryoglobulinemia is classically grouped into three types according to the Brouet classification. These are type 1, type 2 and type 3.

Classification

Cryoglobulinemia is classically grouped into three types according to the Brouet classification.^[1]

	Types of cryoglobulinemia
Associated diseases	Type 1	Type 2	Type 3
Associated diseases	Lymphoproliferative or plasma proliferative disorders(LPD) Monoclonal gammopathy of undetermined significance (MGUS)	Hepatitis C virus Connective tissue disease Idiopathic LPD	Hepatitis C virus Connective tissue disease Idiopathic Other infections

Type I is is a monoclonal immunoglobulin and is most commonly encountered in patients with a plasma cell dyscrasia such as multiple myeloma or Waldenström macroglobulinemia.^[2]

It can lead to a glomerulopathy that is distinct from light chain disease in amyloidosis.

Type II is essential mixed cryoglobulinemia and the cryoglobulins are a polyclonal IgG and a momoclonal IgM rheumatoid factor directed against IgG.
Epstein-Barr Virus (EBV), HIV and Hepatitis B have been implicated but the majority is due to Hepatitis C (HCV).

Type III is also a mixed cryoglobulinemia (MC) where both the IgG and IgM are polyclonal.

It is seen in various autoimmune disorders and lymphoreticular disease as well as hepatitis C in almost 50%.

References

↑ Brouet JC, Clauvel JP, Danon F, Klein M, Seligmann M (1974). “Biologic and clinical significance of cryoglobulins. A report of 86 cases”. Am. J. Med. 57 (5): 775–88. PMID 4216269.
↑ Ferri C, Zignego AL, Pileri SA (2002). “Cryoglobulins”. J. Clin. Pathol. 55 (1): 4–13. PMID 11825916.

Overview