Hepatitis C Virus Infection and Cutaneous Vasculitis in Mixed Cryoglobulinemia: In response

Abstract

Dr. La Civita and colleagues aptly point out the association between chronic hepatitis C virus (HCV) infection, mixed cryoglobulinemia, and leukocytoclastic vasculitis. This letter can be added to a burgeoning amount of evidence that implicates HCV infection as a causative factor for cutaneous vasculitis.1Daoud MS, el-Azhary RA, Gibson LE. Chronic hepatitis C, cryoglobulinemia and cutaneous leukocytoclastic vasculitis: clinical, pathological, and immunopathological study of 10 patients. J Am Acad Dermatol [in press]Google Scholar, 2Karlsberg PL Lee WM Casey DL Cockerell CJ Cruz Jr, PD Cutaneous vasculitis and rheumatoid factor positivity as presenting signs of hepatitis C virus-induced mixed cryoglobulinemia.Arch Dermatol. 1995; 131: 1119-1123Crossref PubMed Scopus (71) Google Scholar All these case reports have common themes. The onset of cutaneous vasculitis seems to occur several years after the patient's initial exposure to or infection with HCV. Although many of the patients have risk factors for HCV infection, the cause of infection is unapparent in many cases. Liver function test results are usually increased at the time of diagnosis of leukocytoclastic vasculitis and HCV infection; however, in some cases, the test results arc normal. Thus, all patients with leukocytoclastic vasculitis of unknown cause should be assessed for HCV infection. Other common laboratory abnormalities in addition to mixed cryoglobulinemia include an increased rheumatoid factor and decreased complement studies, especially C4. Treatment of the HCV infection seems to diminish cutaneous vasculitis, inasmuch as many of these patients have responded favorably to inter-feron therapy. Additional clinical and therapeutic manifestations of this disease continue to unravel at a rapid pace. Hepatitis C Virus Infection and Cutaneous Vasculitis in Mixed CryoglobulinemiaMayo Clinic ProceedingsVol. 71Issue 1PreviewTo the Editor. We read with interest the review by Daoud and colleagues, which was published in the June 1995 issue of the Mayo Clinic Proceedings (pages 559 to 564), that discussed the intriguing association between hepatitis C virus (HCV) infection and skin diseases, one of which was cryoglobulinemic cutaneous vasculitis. The presence of HCV infection has been demonstrated in a large majority of patients with mixed cryoglobulinemia (MC).1 MC is an immune complex (IC)-mediated disorder characterized by purpura, weakness, arthralgias, circulating mixed (IgG and IgM) cryoglobulins, and multiple organ involvementnamely, chronic hepatitis, glomerulonephritis, peripheral neuropathy, and diffuse vasculitis. Full-Text PDF