Comparison of three nucleic acid detection methods for hepatitis E virus

Objective To compare the performance of three nucleic acid detection methods for hepatitis E virus. Methods The open reading frame (ORF) 2 gene sequence of HEV genotype 4 representative strain was cloned into pUC57 vector. Plasmid DNA was detected by two real-time quantitative method A and B, and the detection limits were compared. Other samples were used for specificity detection. Serum specimens of acute hepatitis E patients were detected by three method , and the results were compared. Results The lowest detection limit of plasmid DNA by A and B method can both reach 35 copies/reaction, with specificity of 100%. The HEV RNA positive rate of serum samples from acute hepatitis E patients by A, B and C method was 47.8% (43/90), 43.3% (39/90) and 41.1% (37/90), with the concordance rate of 88.9% (80/90). There was no statistically significant difference among the three method (χ2=0.8414, P=0.6566). Serum specimens with Ct values below 34.6 detected by method A, or below 35.6 detected by method B, the success rate of amplification by method C was 100%. Conclusions Method A has both higher sensitivity and specificity, and method C is a sensitive gene detection method . Key words: Hepatitis E virus; Quantitative real-time polymerase chain reaction; Genotyping