Comparison of real-time fluorescent RT-PCR and conventional RT-PCR for the detection of hepatitis E virus genotypes prevalent in China.
To compare the specificity and sensitivity of a real-time fluorescent RT-PCR assay with conventional RT-PCR, sera from 110 healthy blood donors, 120 patients with a clinical diagnosis of chronic hepatitis B, and 416 patients with non-A-C acute hepatitis, as well as serial dilutions of HEV genotypes 1 and 4, were tested with both assays. All samples from healthy blood donors and patients with chronic hepatitis B were negative by both assays. Real-time RT-PCR could detect the same final dilution of genotype 1 as conventional RT-PCR but could detect a 10-fold lower concentration of genotype 4 than conventional RT-PCR. Of 416 samples from patients with a clinical diagnosis of non-A-C acute hepatitis, 127 (30.5%) and 83 (20.0%) were positive for HEV by real-time and conventional RT-PCR, respectively. The concordance of real-time and conventional RT-PCR was 80.8%. Furthermore, 96 and 57 of 171 samples were positive for anti-HEV IgM by real-time and conventional RT-PCR, respectively, and 31 and 26 of 245 samples negative for anti-HEV IgM, were positive by real-time and conventional RT-PCR, respectively. All amplicons positive by conventional RT-PCR were sequenced. Of 83 isolates, 7 and 76 belonged to genotypes 1 and 4, respectively. Thus, both assays have a high specificity, but the real-time RT-PCR assay is more sensitive than conventional RT-PCR. Furthermore, HEV genotype 4 is responsible for most sporadic cases of hepatitis E in the north of China.
Zhao
Chenyan
C
Department of Cell Biology, National Institute for the Control of Pharmaceutical and Biological Products, Beijing, PR China.
Li
Zhuo
Z
Yan
Baoshan
B
Harrison
Tim J
TJ
Guo
Xinhui
X
Zhang
Feng
F
Yin
Jiming
J
Yan
Yan
Y
Wang
Youchun
Y
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood; D002681:China / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005838:Genotype; D016751:Hepatitis E / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D016752:Hepatitis E virus / Q000235:genetics* / Q000302:isolation & purification*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D015995:Prevalence; D012367:RNA, Viral / Q000097:blood; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D013997:Time Factors
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D012367:RNA, Viral