Article

Evaluation of the Abbott Real-Time HIV-1 quantitative assay with dried blood spot specimens.

Department of Molecular Biology, University of Siena, Siena, Italy.
Clinical Microbiology and Infection (impact factor: 4.54). 01/2009; 15(1):93-7. DOI:10.1111/j.1469-0691.2008.02116.x pp.93-7
Source: PubMed

ABSTRACT The Abbott Real-Time HIV-1 assay was evaluated for its performance in quantification of human immunodeficiency virus type 1 (HIV-1) RNA in dried blood spot (DBS) samples. In total, 169 blood samples with detectable plasma HIV-1 RNA were used to extract RNA from paired DBS and liquid plasma samples, using the automated Abbott m Sample Preparation System (m2000sp). HIV-1 RNA was then quantitated by the m2000rt RealTime analyser. RNA samples suitable for real-time PCR were obtained from all but one (99.4%) of the DBS samples and HIV-1 RNA was detected in 163/168 (97.0%) samples. The correlation between HIV-1 RNA values measured in paired DBS and plasma samples was very high (r = 0.882), with 78.5% and 99.4% of cases differing by <0.5 and 1.0 log, respectively. Retesting of DBS replicates following 6 months of storage at 2-8 degrees C showed no loss of HIV-1 RNA in a subset of 89 samples. The feasibility of DBS testing coupled with automated sample processing, and the use of a latest-generation FDA-approved real-time PCR-based system, represents an encouraging first step for viral load measurement in reference centres in developing countries where access to antiretroviral therapy is expanding.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

169 blood samples
 
2-8 degrees C
 
89 samples
 
Abbott Real-Time HIV-1 assay
 
cases
 
DBS replicates
 
DBS samples
 
detectable plasma HIV-1 RNA
 
encouraging first step
 
HIV-1 RNA
 
HIV-1 RNA values
 
human immunodeficiency virus type 1
 
latest-generation FDA-approved real-time PCR-based system
 
m2000rt RealTime analyser
 
paired DBS
 
real-time PCR
 
reference centres
 
RNA samples suitable
 
sample processing
 
viral load measurement