Summary

Cryoglobulinaemic vasculitis is a small-vessel vasculitis caused by cryoglobulins - immunoglobulins that precipitate at cold temperatures and redissolve on warming. Type I cryoglobulinaemia is associated with haematological malignancies. Types II and III (mixed cryoglobulinaemia) are most commonly associated with hepatitis C infection. Clinical features include palpable purpura, peripheral neuropathy, arthralgia, and membranoproliferative glomerulonephritis. Treatment focuses on the underlying cause (HCV antivirals), with rituximab or plasma exchange for severe manifestations.

Key Facts

• Definition: Vasculitis caused by cold-precipitating immunoglobulins
• Incidence: Rare; associated with HCV in 70-90%
• Peak Demographics: Middle-aged adults
• Pathognomonic: Cryoglobulin positive + palpable purpura + low C4
• Gold Standard Investigation: Cryoglobulin assay (warm transport)
• First-line Treatment: Treat underlying cause; rituximab for severe
• Prognosis: Good if underlying cause treated

Clinical Pearls

Diagnostic Pearl: Sample must be transported at 37°C - cryoglobulins precipitate if cold.

HCV Pearl: Test all cryoglobulinaemia for HCV - it's the most common cause.

Complement Pearl: C4 is characteristically low (classical pathway activation).

Viva Points

"Cryoglobulinaemia: cold-precipitating immunoglobulins. Type I = malignancy; Type II/III = HCV. Features: purpura, neuropathy, MPGN. Low C4. Treat HCV with antivirals; rituximab for severe vasculitis."

Last Reviewed: 2026-01-01 | MedVellum Editorial Team