Cryoglobulinaemic vasculitis

Cryoglobulinaemic vasculitis (CV) is a form of immune mediated primary vasculitis involving small to medium sized vessels. It may involve multiple organs and can have a range of clinical presentations.

Terminology

There are three main types of cryoglobulinaemia which are grouped, as per the Brouet classification, based on the type of immunoglobulin (Ig) produced:

  • type I: isolated monoclonal Ig (most often IgG or IgM)
  • type II: mixture of polyclonal Ig with a monoclonal Ig component (most often IgM or IgA) 
  • type III: mixture of polyclonal Ig without a monoclonal Ig component

Due to containing polyclonal Ig, types II and III are also referred to as 'mixed cryoglobulinaemia'.

Clinical presentation

CV has a very broad and varied clinical presentation. Generally, type I disease presents with symptoms related to hyperviscosity, such as gangrene, Raynaud phenomenon, and neurologic symptoms. Types II and III tend to present with non-specific constitutional symptoms such as arthralgia, purpura, myalgia, and also organ-specific damage such as renal impairment (e.g. due to membranoproliferative glomerulonephritis) or hepatic dysfunction.

Pathology

Cryoglobulins are immunoglobulins (which precipitate when serum is incubated at a temperature lower than the body temperature. Approximately half of patients with cryoglobulinaemia have clinical manifestations of systemic vasculitis caused by small-vessel damage as a result of deposition of immune complexes on small vessel walls and following complex activation.

Associations

Mixed cryoglobulinaemias (types II and III) are most often associated with chronic inflammatory disorders and infections, such as:

Type I, on the other hand, is most often related to B cell lymphoproliferative disorders, such as:

Treatment and prognosis

Treatment and prognosis depends on the underlying associated condition.

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