The histological assessment of cutaneous vasculitis https://onlinelibrary.wiley.com/doi/full/10.1111/j.1365-2559.2009.03443.x
Vasculitic wheel - an algorithmic approach to cutaneous vasculitides
The presence of serum mixed cryoglobulins (MCs) may be an isolated serological finding, the expression of a possible underlying disorder or the hallmark of definite cryoglobulinaemic vasculitis. Cryoglobulinaemic vasculitis is a combination of serological alterations (mainly MCs with rheumatoid factor (RF) activity and frequent low serum complement C4 (C4)) and typical clinico-pathological features (orthostatic purpura, leukocytoclastic vasculitis and multiple organ involvement). HBV, hepatitis B virus; HCV, hepatitis C virus; IC, immune complex.
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