Hepatitis C virus risk: a hepatitis C virus related syndrome.

Background: The association between mixed cryoglobulinemia (MC) and hepatitis C virus (HCV) infection has been recently described in many reports.
Objective: The aim of this study was to evaluate the long-term prognosis of hepatitis C virus-positive patients affected by mixed cryoglobulinemia with or without kidney involvement.
Patients: At total of 119 hepatitis C virus-positive patients affected by mixed cryoglobulinemia were divided in two groups. Group A: mixed cryoglobulinemia without kidney involvement (103 cases); group B: mixed cryoglobulinemia with glomerulonephritis (GN) (16 cases). A further 37 patients affected by mesangio-proliferative glomerulonephritis (MPGN) were evaluated as controls (group C).
Methods: Anti-hepatitis C virus antibodies were determined by commercial kits and hepatitis C virus-RNA was detected by polymerase chain reaction (PCR) amplification of the 5' untranslated region (5'UTR) of the virus. The hepatitis C virus genotype was determined according to Okamoto. Liver biopsy was performed in 62 patients, bone marrow biopsy in 65 patients, and kidney biopsy in all patients with proteinuria.
Results: In group A, 46 patients (45%) were affected by chronic liver disease (CLD), 21 (20%) by low-grade non-Hodgkin's lymphoma (NHL) and 16 (15%) by both diseases. All patients of group B were affected by type I membrano-proliferative glomerulonephritis, 3 (19%) by chronic liver disease, 6 (37%) by low-grade non-Hodgkin's lymphoma, and 7 (44%) by both diseases. Several genotypes of hepatitis C virus were found, but Type 1b was prevalent. In group C, no patient showed chronic liver disease or non-Hodgkin's lymphoma. Younger age, higher mean blood pressure, lower C4 serum level, and poorer survival significantly distinguished group B from group A. Survival rates at 5 years were: 87.4% for group A, 89.5% for group C, and 50.0% for group B. None of the patients of group B developed kidney failure requiring dialysis, whilst infections were the leading cause of death.
Conclusions: In hepatitis C virus-positive patients, the presence of mixed cryoglobulinemia associated with kidney involvement seems to indicate a new syndrome characterized by immune system impairment, lack of progression to kidney failure, and poor survival (hepatitis C virus-Risk syndrome).