Saturday 20 November 2010

MRCP revision battle 55.3: Cryoglobulins

Cryoglobulins are immunoglobulins that undergo reversible precipitation at 4c and dissolve when warmed to 37c.

Cryoglobulins may be IgG, IgM or IgA.

One third of cases are idiopathic.



Type 1 cryoglobulinaemia
  • monoclonal
  • high titres, usually >5mg/ml
  • associated with:
    • myeloma
    • Waldenstroms
  • features include vasculitis, ulceration and Raynaud's

Type 2 cryoglobulinaemia
  • mixed mono and polyclonal
  • titres usually >1mg/ml
  • associated with:
    • RA
    • sjogrens
    • lympoma
    • CLL
    • hep C
    • HIV
  • features include vasculitis, mesangiocapillary GN


Type 3 cryoglobulinaemia
  • mixed polyclonal
  • associated with:
    • RA
    • sjogrens
    • SLE
  • features include purpura, GN, arthritis


Now on to a similar but distinct topic...