Can cryoglobulinemia trigger ANCA vasculitis?

• Main Author: Cunha,Ivo
• Publication Date: 2020
• Other Authors: Santos,M. Teresa, Pereira,P. Ricardo
• Format: Report
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-01692020000100009
• topic: Crescents; cryoglobulinemia; interstitial nephritis; rapidly progressive glomerulonephritis; vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a rare and heterogeneous group of autoimmune diseases. These pauciimmune vasculitis differ from the cryoglobulinemic vasculitis mediated by immune complexes. We report the case of a 79-year-old male with silicosis and chronic alcoholic liver disease, presenting with a rapidly progressive glomerulonephritis and pancytopenia. Work-up revealed hypocomplementemia, polyclonal hypergammaglobulinemia, type 3 cryoglobulinemia, p-ANCA positivity and elevated anti-MPO. Renal biopsy showed a pattern of chronic interstitial nephritis with fibrocellular crescents, and immunofluorescence staining was negative. Treatment was started with corticosteroids and rituximab with improvement of the renal function, decrease of the anti-MPO titer and disappearance of the cryoglobulinemia. In this case, renal injury was caused by ANCA vasculitis, whose etiology remains unknown despite the recognizable risk factor for ANCA formation (silicosis). The importance of the cryoglobulinemia is not clear, as it could be part of the pathogenesis or just an epiphenomenon secondary to the autoimmune and the chronic liver diseases.