Quantitative detection of hepatitis C virus genome in liver tissue and circulation by competitive reverse transcription-polymerase chain reaction.

We quantified hepatitis C virus RNA in 25 Japanese patients with chronic type C liver disease by competitive reverse transcription-polymerase chain reaction. The amount of the viral RNA in the serum (2 x 10(5)-2 x 10(8) copies/ml) correlated with that in the liver tissue (10(8)-10(11) copies/g) (N = 23, r = 0.727, P < 0.0001). One gram of the infected liver tissue contained 10(2)-10(4) (geometric mean, 10(3), N = 23) times as many copies of the viral RNA as did 1 ml of the serum. Liver tissues of chronic aggressive hepatitis contained significantly higher amounts of the viral RNA than those of chronic persistent hepatitis (P < 0.05). These observations suggested that this method is useful to evaluate viral amount, and the amount of the circulating hepatitis C virus RNA could be used as a marker of the intrahepatic viral amounts, which might contribute to disease activity.