[Direct-acting antiviral agents improved nephrotic syndrome associated with refractory pleural effusion and ascites caused by hepatitis C virus-related nephropathy: a case report].

A 74-year-old man with hepatitis C virus (HCV)-related cirrhosis was admitted because of dyspnea. Laboratory investigations revealed severe proteinuria (4.0g/day), low serum albumin level, and cryoglobulinemia. Computed tomography showed massive pleural effusion and ascites. Because these effusions were leaky and the hepatic reserve was relatively intact, we thought these were mainly caused by nephrotic syndrome. Renal biopsy revealed membranoproliferative glomerulonephritis with mesangial proliferation and excessive matrix deposition. Based on these histopathological findings and the presence of cryoglobulinemia, a diagnosis of HCV-related nephropathy was performed. Therefore, antiviral therapy was initiated with direct-acting antiviral (DAA) agents (daclatasvir+asunaprevir). Serum HCV-RNA level was observed to be negative at week 8, which was followed by an alleviation of proteinuria and a gradual decrease in the pleural effusion and ascites. HCV-related nephropathy should be considered in the differential diagnosis of patients with chronic hepatitis C and refractory ascites. DAA agents are effective in the treatment of these patients.