Patterns of viraemia in haemodialysis patients with hepatitis C

Clinical features, aminotransferases levels, and antibody to HCV have only limited correlation with the activity of liver disease and cannot accurately predict persistence versus eradication of the virus in haemodialysis patients. Although permanent loss of serum HCV RNA appears to correlate with resolution of the disease, little is known about the predictive value of a single HCV RNA value. The aim of the study was to evaluate the viraemia in the serum of HCV antibody positive haemodialysis patients during a period of 3 years. The study group consisted of 65 HCV antibody positive patients from our dialysis unit. HCV antibodies were measured every 6 months by ELISA third-generation assay. The presence of serum HCV RNA was assessed by reverse-transcriptase polymerase chain reaction (RT-PCR) once a year during the period of 3 years. Serum levels of aminotransferases were measured monthly with standard automated analyzers. There were three different patterns of viraemia after the third assessment of the serum HCV RNA in HCV antibody positive patients: 47% (30/65) were persistently HCV RNA positive, 38% (25/65) were intermittently HCV RNA positive, and 15% (10/65) were persistently HCV RNA negative. The dominant genotype was 1a, detected in 97% of the patients positive for HCV RNA. The HCV RNA persistently positive patients had significantly higher levels of ALT compared to HCV RNA persistently negative patients (50.07 +/- 30.0 vs. 28.5 +/- 10.0 U/L, p < 0.027). There was no significant difference between the three groups of patients according to age, haemodialysis duration, and serum levels of AST. This pattern of intermittent viraemia clearly showed that a single negative result of the presence of serum HCV RNA in an HCV antibody positive patient should not be taken as a proof of a persistent resolution of HCV. Thus, repeated testing for HCV RNA is necessary to assess viraemia accurately in HCV antibody positive patients. HCV antibody positive patients who were persistently serum HCV RNA negative could be potentially infectious because of the possibility of the persistence of occult hepatitis C.