Cryofibrinogenemia: a marker of severity of cryoglobulinemic vasculitis

Cryofibrinogenemia is frequently associated with cryoglobulinemia. The aim of this study was to determine the characteristics associated with the presence of cryofibrinogenemia in patients with cryoglobulinemic vasculitis.

This was a single-center retrospective study that included patients with cryoglobulinemic vasculitis who were tested for cryofibrinogen at a tertiary referral center between January 1, 2011 and December 31, 2012. Twenty-nine patients fulfilled the CryoVas (cryoglobulinemic vasculitis) Survey criteria for cryoglobulinemic vasculitis. Eighteen patients had a detectable cryofibrinogen (CF-positive) and 11 had no detectable cryofibrinogen (CF-negative). Median cryoglobulin levels were 89 ± 129 mg/L in the CF-positive group and 68 ± 82 mg/L in the CF-negative group (P = .32). Median cryofibrinogen level was 70 ± 174 mg/L. Clinical manifestations were similar in both groups. Cancers and hematological disorders were more frequent among CF-positive patients (39% vs 0%, P = .026). Levels of alpha-1 and alpha-2 globulinemia were higher in the CF-positive group. Cryofibrinogenemia ≥ 100 mg/L was associated with cryoglobulinemic vasculitis (odds ratio [OR] 2.86; 95% confidence interval [CI], 1.06-7.73) in cryoglobulinemic patients. Presence of cryofibrinogenemia was associated with use of corticosteroids, immunosuppressants, or plasmapheresis in cryoglobulinemic vasculitis patients (OR 22.7; 95% CI, 2.02-256.44).

Our results strongly suggest that presence of cryofibrinogenemia is associated with a more severe phenotype among patients with cryoglobulinemic vasculitis.