Transcription-mediated amplification (TMA) for the assessment of viremia in hemodialysis patients with hepatitis C.

The diagnosis of hepatitis C virus (HCV) infection in hemodialysis patients is difficult particularly due to the presence of intermittent viremia. The aims of this study were: (a) to determine the prevalence of intermittent viremia in hemodialysis patients with anti-HCV antibodies who tested negative for HCV RNA by PCR at the first evaluation and (b) to evaluate the contribution of the transcription-mediated amplification method (TMA) to the diagnosis of viremia in the PCR-negative samples. One hundred and six patients with anti-HCV antibodies and an initial negative result for HCV RNA by PCR were included. An additional sample was collected for a second HCV RNA test by PCR after a minimum interval of 3 months and a positive result characterized intermittent viremia. HCV RNA was investigated by TMA in the PCR-negative sample of patients with intermittent viremia, and in the most recent sample from patients with PCR-negative results in both determinations. Intermittent viremia was observed in 60/106 (57%) patients (57% men; age: 45 ± 10 years). Fifty-one of the 60 negative samples from patients with intermittent viremia and 29/46 double-negative patients were tested by TMA. This assay detected viremia in 20/51 (39%) samples of intermittent viremia and in 2/29 (7%) of double-negative samples. The results showed that intermittent viremia is frequent in hemodialysis patients who tested negative for HCV RNA by PCR. Therefore, a second HCV RNA test is necessary for all HCV RNA-negative patients. The TMA assay appears to be the best first screening test for viremia in this population.

Long-term efficacy of rituximab in hepatitis C virus-associated cryoglobulinemia.

Mixed cryoglobulinemia is one of the most closely related extrahepatic manifestations of hepatitis C virus and requires a challenging therapeutic approach depending on the severity of the symptoms. Here, we describe the long-term follow-up of a patient with important cutaneous, articular and neural manifestations of cryoglobulinemia associated with chronic hepatitis C treated with rituximab. A 42-year-old woman who did not respond to previous interferon-based treatments (standard and pegylated interferon plus ribavirin) and corticosteroids was subjected to treatment with rituximab at a dose of 375 mg/m(2) per week for 4 consecutive weeks. The drug was well tolerated and complete improvement of arthralgia was immediately evident. There was gradual improvement of lower limbs paresthesia and healing of a leg ulcer that had been active for 5 years. The clinical and immunological responses induced by rituximab are sustained over long-term follow-up, and this case illustrates the drug efficacy for non-responder patients to antiviral therapy.