In:
Journal of Clinical Microbiology, American Society for Microbiology, Vol. 47, No. 10 ( 2009-10), p. 3231-3240
Abstract:
Quantitation of hepatitis C virus (HCV) RNA in plasma and serum samples is a costly procedure in both time and reagents. Additionally, cell-associated viral RNA may not be detected. This study evaluated the accuracy of HCV RNA quantitation in small-volume whole-blood (WB) samples, which would be appropriate for point-of-care diagnostic devices. HCV RNA was extracted from 222 clinical plasma and WB samples of 82 patients with chronic hepatitis C by a specific locked nucleic acid-mediated capture method and quantified by real-time reverse transcription-PCR. The results were compared to the reference plasma viral load determined with the COBAS AmpliPrep/TaqMan (CAP/CTM) HCV test. This assay had an analytical sensitivity of 9 IU per 10-μl sample (95% limit of detection [95% LOD] ), a linearity range of 500 to 5 × 10 6 IU/ml, and was accurate in testing 10 HCV subtypes ( 〈 0.22 log 10 unit) in plasma. The assay was matrix equivalent for plasma and WB samples (coefficient of determination [ R 2 ] of 0.943) and had a specificity of 100% ( n = 20) in WB samples. The HCV RNA concentration in clinical WB samples exceeded the estimated hematocrit-corrected plasma viral loads by 0.22 log 10 unit, but absolute quantitation results in plasma and WB samples were identical (95% confidence interval, −0.06 to 0.04 log 10 unit). The sensitivity in WB samples was 100% ( n = 141) for plasma concentrations above the 95% LOD. Quantitation results in 10-μl WB samples correlated linearly with the CAP/CTM HCV plasma test results ( R 2 = 0.919; n = 140) and did not differ between capillary and venous samples ( R 2 = 0.960; n = 40). This study shows that HCV RNA quantitation in 10-μl WB samples is appropriate for monitoring viral loads of 〉 900 IU/ml, although the use of WB does not increase the diagnostic sensitivity.
Type of Medium:
Online Resource
ISSN:
0095-1137
,
1098-660X
DOI:
10.1128/JCM.00925-09
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2009
detail.hit.zdb_id:
1498353-9
SSG:
12
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