Cryoglobulinemic Vasculitis

Journal/Book: Z Rheumatol 1998; 57 Suppl. 1: 15 (V 62). 1998;

Abstract: Clinical Immunology Unit Dept. of Internal Medicine University of Pisa Mixed cryoglobulinemia (MC) is a systemic vasculitis characterized by the presence of cryoglobulins with rheumatoid factor activity. Although MC is a disease of multifactorial origin HCV plays a central role in its pathogenesis. The disease is an immunocomplex-mediated disorder with a number of immunologic phenomena often triggered by HCV infection. The nature of the organ damage depends on the nature of the antigen and on the type of the immune response. HCV like other RNA viruses is characterized by a high degree of genetic heterogeneity that may arise either spontaneously or as a result of host immune pressure. Mutation of the HCV genomc during replication in a single infected individual results in a quasi-species genotype distribution while the accumulation of mutations during the evolution of the virus has led to the emergence of several genotypes. At present HCV has been divided into three major genetic groups (genotypes 1 2 and 3) and six subgroups [genotypes 1a (I) 1b (II) 1c 2a (III) 2b (IV) and 3a (V)]. A higher prevalence of genotype 2a has been found in MC patients than in chronic HCV carriers without MC. Most of the patients with chronic HCV infection do not develop MC: the percentage ranges from 15 to 54 % among different series. Among these patients only few develop the full blown cryoglobulinemic syndrome. This indicates that other factors in addition to HCV infection are needed for the development of the cryoglobulinemic syndrome. The individual reactivity to the viral antigens probably plays a role in Ihe appearance of the different disorders associated with HCV infection. ... le

Zurück | Weiter