[Stability of hepatitis C virus RNA in various processing and storage conditions]

The study was purposed to investigate whether processing and storage conditions might influence the stability of the HCV RNA in whole blood or in plasma. The samples obtained from seven patients known to be positive for HCV RNA were kept in different storage conditions with different anticoagulants, and at the end of processing the plasma samples were frozen at -80 degrees C until fluorescent quantitative PCR testing. The results showed that there was no significant loss of HCV RNA titers in whole blood anticoagulated with CPDA or ACD or EDTA or none (P > 0.05), while differences in comparison of the EDTA-anticoagulant storage condition with three other anticoagulants storage conditions at 4 degrees C after 48 hours were significant (P < 0.05). The HCV RNA level decreased to 53.8%, 72.5% and 29.8% after 48 hours of storage of whole blood anticoagulated with ACD at 4 degrees C, 25 degrees C and 37 degrees C respectively. The HCV RNA level of plasma samples stored at 4 degrees C and at 25 degrees C (room temperature) after 7 days decreased to 70.9% and 25.1% respectively. After four freeze-thaw cycles the HCV RNA level decreased 38.9% in plasma samples. It is concluded that the HCV RNA is stable relatively. The HCV RNA is resistant to degradation under routine laboratory handling and storage conditions or blood collection, transport and processing conditions. The influence of different anticoagulants on the stability of HCV RNA is different. Blood samples would better be stored at 4 degrees C after collection and plasma separated within 48 hours. And it is important for the stability of HCV RNA undergoing asepsis blood collection process. HCV RNA remains stable at 4 degrees C for at least 7 days or at room temperature for 3 days, allowing greater flexibility in samples collection and transport in transfusion practice nowadays. HCV RNA in plasma samples subject to up to three short-term freeze-thaw cycles is still stable.