Does the antiviral therapy of patients with chronic hepatitis exert nephrotoxic effects?

A Case of Cryoglobulinemic Membranoproliferative Glomerulonephritis Induced by Hepatitis C Virus

A 61-year-old man with bilateral purpura of the lower limbs and subsequent edema, was hospitalization after renal dysfunction developed. The presence of hepatitis C virus (HCV) RNA and cryoglobulin and the finding of membranoproliferative glomerulonephritis on renal biopsy led to a diagnosis of HCV-related glomerulonephritis due to cryoglobulinemia. Because of the pre-existence of nephrotic syndrome and the continuously increasing serum level of creatinine, treatment with cryofiltration, interferon, and steroids was started. After 5 cryofiltration sessions, the cryocrit level had decreased to 1% and the levels of serum creatinine and proteinuria had also decreased. However, 3 weeks after the start of treatment, nephrotic syndrome developed again and was accompanied by lower-extremity mononeuropathy and renal dysfunction. Thereafter, the patient showed disorientation, an affective disorder, and delirium, and his condition gradually deteriorated. Radiological examination of the head and examination of the cerebrospinal fluid showed no abnormalities. Despite the withdrawal of the interferon therapy and the reduction of the steroid dose, the patient's conditions remained unchanged, and the level of consciousness deteriorated. Although cryofiltration had beneficial effects and plasma exchange was continuously performed, the patient died on the 74th hospital day. Because of the significant changes due to ventilatory support and hemorrhage associated with disseminated intravascular coagulation, the autopsy findings did not allow us to definitively determine whether the symptoms had been caused by the HCV-related membranoproliferative glomerulonephritis or the interferon therapy or both. We have reported this case to provide insight into whether interferon therapy should be administered for HCV-related membranoproliferative glomerulonephritis with marked neurological symptoms due to cryoglobulinemia.

Management of hepatitis C in patients with chronic kidney disease

Hepatitis C virus (HCV) infection is highly prevalent among chronic kidney disease (CKD) subjects under hemodialysis and in kidney transplantation (KT) recipients, being an important cause of morbidity and mortality in these patients. The vast majority of HCV chronic infections in the hemodialysis setting are currently attributable to nosocomial transmission. Acute and chronic hepatitis C exhibits distinct clinical and laboratorial features, which can impact on management and treatment decisions. In hemodialysis subjects, acute infections are usually asymptomatic and anicteric; since spontaneous viral clearance is very uncommon in this context, acute infections should be treated as soon as possible. In KT recipients, the occurrence of acute hepatitis C can have a more severe course, with a rapid progression of liver fibrosis. In these patients, it is recommended to use pegylated interferon (PEG-IFN) in combination with ribavirin, with doses adjusted according to estimated glomerular filtration rate. There is no evidence suggesting that chronic hepatitis C exhibits a more aggressive course in CKD subjects under conservative management. In these subjects, indication of treatment with PEG-IFN plus ribavirin relies on the CKD stage, rate of progression of renal dysfunction and the possibility of a preemptive transplant. HCV infection has been associated with both liver disease-related deaths and cardiovascular mortality in hemodialysis patients. Among those individuals, low HCV viral loads and the phenomenon of intermittent HCV viremia are often observed, and sequential HCV RNA monitoring is needed. Despite the poor tolerability and suboptimal efficacy of antiviral therapy in CKD patients, many patients can achieve sustained virological response, which improve patient and graft outcomes. Hepatitis C eradication before KT theoretically improves survival and reduces the occurrence of chronic graft nephropathy, de novo glomerulonephritis and post-transplant diabetes mellitus.