Previous Article | Next Article ![]()
Journal of Clinical Microbiology, May 1997, 1184-1189, Vol 35, No. 5
N Yuki, N Hayashi, E Mita, H Hagiwara, K Ohkawa, K Katayama, Y Sasaki, A Kasahara, H Fusamoto and T Kamada
We studied factors which influence the detection of hepatitis C virus
genotypes by the group-specific PCR of the sequence within the core region
gene and by the newly developed genotype-specific NS4 antibody assay.
Genotyping was performed on 75 hepatitis C virus carriers in Japan, where
patients with hepatitis C viremia are exclusively infected with genotype
1b, 2a, and 2b. PCR failed to identify genotypes in 8 (11%) patients,
whereas 12 (16%) patients, including the 8 patients mentioned above, could
not be genotyped by the serological assay. Serological genotypes showed
almost complete agreement with those found by the PCR except that double
infection was revealed in only two of the eight patients serologically
judged to be coinfected with genotypes 1 and 2. In each assay, disease
activity and levels of viremia assessed by a competitive reverse
transcription PCR assay were significantly lower in patients infected with
untypeable isolates than in those infected with typeable ones (P <
0.01). The PCR could identify the genotypes of isolates from all 64
patients with levels of viremia of > or = 10(6) copies/ml, and the
genotype-specific antibody responses were found in 60 (94%) patients. In
contrast, isolates from only 3 (27%) of 11 patients with low levels of
viremia (< 10(6) copies/ml) could be genotyped by the PCR (P <
0.00001), and these patients showed the genotype-specific antibody
responses (P < 0.00001). These findings suggest that low levels of
hepatitis C virus replication may reduce the efficiency of genotyping by
serological assay as well as by PCR.
Copyright © 1997 by the American Society for Microbiology. All rights reserved.
Hepatitis C virus replicative levels and efficiency of genotyping by specific PCR and antibody assay
First Department of Medicine, Osaka University Medical School, Suita, Japan.
This article has been cited by other articles:
| Antimicrob. Agents Chemother. | Clin. Microbiol. Rev. |
|---|---|
| Clin. Vaccine Immunol. | ALL ASM JOURNALS |
|---|