Validation and evaluation of Roche Cobas S201 system in blood screening for nucleic acid detection and amplification / 中国输血杂志

ABSTRACT

【Objective】 To verify the key performance parameters of Roche Cobas S201 multiplex NAT for blood donors, so as to provide data for the conformation of multiplex NAT performance and establish a scientific and feasible verification scheme. 【Methods】 Comprehensive performance verification on four key parameters of ROCHE COBAS S201 multiplex NAT system, including the 95% detection limit, compliance rate, anti-interference ability and operator comparison were conducted. The data were compared with the specifications provided by the manufacturer to evaluate the performance of laboratory testing system and ensure the quality of blood testing. 【Results】 2 sets of COBAS S201 multiplex NAT system in our laboratory were used to perform 5 times of the 95% detection limit value declared by the manufacturer for individual tests. The experimental results showed that the target NAT can be detected 100% and the lower limit of determination was verified. Single-virus NAT was performed to detect 5 different HBV DNA concentrations (25 ~400 IU/mL), 5 different HCV RNA concentrations (25 ~400 IU/mL), 5 different HIV RNA Concentration (100~1 000 IU/mL), and 5 negative tubes. The experimental results showed that all detected values of 20 tubes were 100% consistent with the true value, and the performance parameter "coincidence rate" was verified. Samples containing lipoemia, hemolysis, with ALT>50 mL/L and syphilis-positive endogenous interfering substances with 3 times of the 95% detection limit value were tested for 3 times, and results showed both response rate (3/3) and yielding rate reached 100%. In the control group (with none or in the normal range of interfering substances), reactivity was detected in samples with extremely low concentration of 3 times of the 95% detection limit, showing no significant difference (P>0.05). Above results fully showed that the existence of interference substances (lipidemia, hemolysis, ALT ≥ 50 and syphilis positive) in the blood of donors had no significant effect on the yielding of HBV/HCV/HIV virus target nucleic acids. Different operators performed the sample loading tests with same instrument, reagent and specimen showed 100% consistency in the results. It could be preliminarily assessed that there was no difference in the operations between the operators in this verification. 【Conclusion】 The verification scheme of the multiplex NAT system for methodology performance index (95% detection limit, coincidence rate, anti-interference ability, and operator comparison) established in this study, showed simple, flexible, scientific and feasible characteristics and could provide reference and data support for domestic blood transfusion services in acid detection.