Cryoglobulinémie mixte symptomatique au cours de l’hépatite virale C

Abstract

Cryoglobulins are immunoglobulins that reversibly precipitate in the cold. They may lead to an immune complex-mediated vasculitis, which may sometimes be severe. A wide range of conditions may be related to cryoglobulinaemia, and the most frequent of them is chronic hepatitis C. The purpose of this work was to emphasize the diagnostic and therapeutic characteristics of cryoglobulinaemia associated with hepatitis C. A 55-year-old woman, with a history of arterial hypertension, was admitted with transudative ascites. Clinical investigation revealed purpuric lesions and oedema of the lower limbs with Raynaud phenomenon. Proteinuria and haematuria were detected in the urine test strip. The patient had a positive serology for hepatitis C, but no signs of portal hypertension. Further investigations showed renal failure with nephrotic syndrome. Renal biopsy showed membranous proliferative glomerulonephritis with parietal and mesangial deposits of IgM and IgG antibodies. Skin biopsy showed leucocytoclastic vasculitis. Immunological investigations found type IIb mixed cryoglobulinaemia associated with hepatitis C. The patient was treated by pegylated interferon and ribavirin. She showed a satisfactory clinical and a sustained virological response for 1 year after the withdrawal of therapy. Mixed cryoglobulinaemia is the main extrahepatic manifestation of hepatitis C, but it is rarely symptomatic. The combination of peginterferon-α and ribavirin leads to virological and clinical responses of vasculitis in most patients.