RT Journal Article SR Electronic T1 Observations on Cryoglobulin Testing: I. The Association of Cryoglobulins Containing Rheumatoid Factors with Manifestation of Cryoglobulinemic Vasculitis JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 1953 OP 1955 DO 10.3899/jrheum.081035 VO 36 IS 9 A1 FRANCESCO G. DE ROSA A1 VINCENT AGNELLO YR 2009 UL http://www.jrheum.org/content/36/9/1953.abstract AB Objective. To investigate the results of mixed cryoglobulin tests performed on patients with and without hepatitis C virus (HCV) infection, to determine whether type II cryoglobulins containing rheumatoid factor (Type II-RF) were associated with cryoglobulinemic vasculitis. Methods. The cryoglobulin test protocol differed from the routine protocol. In addition to determination of both cryoglobulin concentration and immunoglobulin composition, the presence or absence of RF concentrated in the cryoglobulins was determined. Results. A qualitative and quantitative association of Type II-RF cryoglobulins with cryoglobulinemic vasculitis was present among HCV-infected patients. Conclusion. Detection and quantification of Type II-RF may enhance clinical monitoring of cryoglobulinemic vasculitis in HCV-infected patients.