Mixed cryoglobulinemia vasculitis (Cryovas) is a small vessel vasculitis involving mainly the skin, the joints, the peripheral nerve system and the kidneys. Hepatitis C virus (HCV) infection is the cause of Cryovas in about 80% of cases. The disease expression is variable, ranging from mild symptoms (purpura, arthralgia) to fulminant life-threatening complications (glomerulonephritis, widespread vasculitis). Most HCV-Cryovas manifestations respond to clearance of HCV during antiviral therapy. Patients who relapse for HCV infection after responding to antiviral therapy usually relapse for the Cryovas with the return of viremia.
Interferon alpha-based therapy has long been the cornerstone of HCV-Cryovas treatment. In the early 2010's, use of triple HCV therapy with pegylated-interferon/ribavirin and a direct antiviral agent (DAA, boceprevir or telaprevir) led to improved rates of sustained virological response and Cryovas remission. However, frequent side effects limited the use of such combinations. During the last two years, all oral interferon-free, DAA regimens have been used in HCV-Cryovas, associated with very high rates of sustained virological response and clinical remission of the Cryovas, and few toxicities. In daily practice, HCV-Cryovas patients with mild to moderate disease should be given an optimal all oral, interferon-free, DAA regimen. For patients with severe vasculitis control of disease with rituximab, with or without plasmapheresis, is required while starting optimal antiviral therapy. Other immunosuppressants should be given only in case of refractory forms of HCV-Cryovas.
Disclosure of Interest P. Cacoub Shareholder of: ILTOO pharma, Speakers bureau: Abbvie, Astra Zeneca, Bayer, Boehringer Ingelheim, Gilead, Glaxo Smith Kline, Janssen, Merck Sharp Dohme, Pfizer, Roche, Servier, Vifor.