Cryofibrinogenemia: a marker of severity of cryoglobulinemic vasculitis.

ABSTRACT

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