Quantitative detection of hepatitis C virus RNA in patients undergoing hemodialysis

The purpose of the current study was to detect quantitatively hepatitis C virus (HCV)-RNA among patients undergoing maintenance hemodialysis. Study subjects were 88 patients on hemodialysis at the Miami Veterans Administration Medical Center and the REN Dialysis Unit at the University of Miami School of Medicine. There were 66 men and 22 women, mean age 52 years (range, 22-87 years), and mean duration of dialysis was 2.8 years (range 0.2-12.5 years). Seventy-three percent had a history of blood transfusion. Anti-HCV was determined by enzyme linked immunosorbent assay (ELISA), confirmed by four antigen strip immunoblot assay (RIBA 2.0 SIA). HCV-RNA was quantitated directly in human sera using a branched DNA (bDNA) signal amplification assay. Twenty-seven of 88 (31%) patient samples were found to be anti-HCV reactive by ELISA. Twenty-two of 27 were confirmed reactive, 2 were indeterminate, and 3 were nonreactive by RIBA HCV. Eighteen of 22 (82%) reactive by RIBA 2.0 HVC were found to have detectable (> 3.5 X 10(5) Eq/ml) HCV-RNA levels (mean [&/- SD], 43.3 +/- 35.4 X 10(5) Eq/ml; range 4.9-123.3). No additional cases were identified with reverse transcription polymerase chain reaction (RT-PCR) using 5' untranslated region "nested" primers. HCV-RNA was not detected in four RIBA HCV 2.0 reactive, the two intermediate, or the 64 patient samples nonreactive for anti-HCV. The two epitopes most commonly associated with HCV-RNA were c22-3 and c33c. Sixteen of 18 (89%) patients with detectable levels of HCV-RNA had normal alanine aminotransferase (ALT). Three patients with the highest levels of HCV-RNA were infected with the human immunodeficiency virus. The authors conclude that HCV-RNA by bDNA assay is a sensitive, specific, and simple test that can be used in association with antibody assays and a PCR-based assay to study the prevalence and management of HCV infection in the dialysis setting.