[Specific damage to the kidneys in patients with chronic hepatitis C associated with cryoglobulinemia].

Aim: To reveal clinical and morphological characteristics of renal damage in patients with cryoglobulinemia (CGE) associated with chronic viral hepatitis C (CVH-C) for upgrading diagnosis, prognosis and optimization of the treatment methods.
Material and Methods: Two groups of CVH-C patients were studied: with CGE (group 1, n = 64) and free of CGE (group 2, n = 62) matched for gender, age and duration of the disease. Biopsy of the liver for assessment of the histological activity index and histological sclerosis index by METAVIR scale was conducted in 63 patients. Of patients with CGE-related damage to the kidneys, 48 were examined for clinical picture with morphological investigation of renal tissue in 15 of them including semiquantitative evaluation of fibrosis degree and activity.
Results: Patients with CVH-C and CGE had a wider spectrum of systemic lesions than CVH-C patients without CGE. Only CGE patients demonstrated more severe affection of the skin, joints, kidneys and the nervous system. Therefore, CGE can be considered as a marker of poor prognosis. Liver biopsy showed that CGE patients had more pronounced fibrosis (3-6 points) versus 0-2 points in 80% patients from group 2. Duration of CVH-C from probable infection to renal damage in 48 patients with CGE glomerulonephritis (GN) averaged 197.05 +/- 18.5 months. Renal biopsy diagnosed CGE mesangiocapillary GN in 13 patients and membranoproliferative GN in 2 patients. Patients with HCV infection had a more severe proliferative form of nephritis--mesangiocapillary GN. In 48 GN patients with HCV-infection and CGE, GN ran latently with moderate urinary syndrome in 29 (60.4%) patients, with nephrotic syndrome--in 9 (18.6%), with acute nephritic syndrome--in 10 (21.0%) patients. Most of the patients had arterial hypertension, 13 patients had creatinemia (3.02 +/- 0.55 mg/dl), rapidly progressive GN was diagnosed in 4 patients.
Conclusion: Persistent CGE marks poor prognosis in CHC patients and is an indication for antiviral treatment to prevent severe organ lesions, first of all of the kidneys. Development of CGE vasculitis with severe damage to the kidneys demands immunosuppressive therapy in combination with plasmapheresis or cryapheresis followed by antiviral drugs. As shown by pilot results, a new approach with rituximab is perspective but further evidence is needed for final conclusions.