Rocco Misiani, MD; Piermario Bellavita, MD; Domenico Fenili, BiolScD; Giuseppe Borelli, BiolScD; Donatella Marchesi, MD; Margherita Massazza, MD; Giovanni Vendramin, MD; Benedetto Comotti, MD; Elisabetta Tanzi, PhD; Guido Scudeller, MD; Alessandro Zanetti, PhD
▪ Objective: To study the association between hepatitis C virus (HCV) infection and essential mixed cryoglobulinemia.
▪ Setting: Wards and clinics of the Ospedali Riuniti di Bergamo and Ospedale di Treviglio e Caravaggio, Italy.
▪ Patients: Fifty-one patients with essential mixed cryoglobulinemia associated with glomerulonephritis and 45 controls with noncryoglobulinemic glomerulopathies.
▪ Measurements: Antibodies to hepatitis C virus (anti-HCV) in sera from patients with essential mixed cryoglobulinemia and from controls, using two enzyme-linked immunosorbent assays (c100 ELISA and c22/c200 ELISA) and a recombinant immunoblot assay (4-RIBA); cryoprecipitate anti-HCV before and after use of dithiothreitol, a substance able to destroy IgM antibodies with rheumatoid factor activity, in patients with essential mixed cryoglobulinemia; serum HCV RNA by polymerase chain reaction in patients with essential mixed cryoglobulinemia.
▪ Results: In patients with essential mixed cryoglobulinemia, the c22/c200 ELISA detected anti-HCV in 98% of serum samples (95% Cl, 90% to 100%), whereas the rate of reactivity remained at 2% (Cl, 0% to 12%) in the control group (P < 0.0001). These results were confirmed by the 4-RIBA in 66% of patients with essential mixed cryoglobulinemia. The study of cryoprecipitate by c100 ELISA showed anti-HCV in 41% (Cl, 28% to 56%) of patients. After dithiothreitol, the rate of reactivity increased to 94% (Cl, 84% to 99%; P < 0.0001 by the McNemar paired chi-square test), suggesting that the elimination of rheumatoid factor leads to unmasking of anti-HCV in cryoprecipitate. Polymerase chain reaction detected HCV RNA in 13 of 16 sera from patients with essential mixed cryoglobulinemia.
▪ Conclusions: The extremely high prevalence of anti-HCV in serum and cryoprecipitate along with the frequently associated serum HCV RNA suggests a close relation between essential mixed cryoglobulinemia and chronic HCV infection.
Misiani R, Bellavita P, Fenili D, Borelli G, Marchesi D, Massazza M, et al. Hepatitis C Virus Infection in Patients with Essential Mixed Cryoglobulinemia. Ann Intern Med. ;117:573–577. doi: 10.7326/0003-4819-117-7-573
Download citation file:
Published: Ann Intern Med. 1992;117(7):573-577.
Copyright © 2018 American College of Physicians. All Rights Reserved.
Print ISSN: 0003-4819 | Online ISSN: 1539-3704
Conditions of Use