Measuring human immunodeficiency virus type 1 RNA loads in dried blood spot specimens using NucliSENS EasyQ HIV-1 v2.0.

摘要

BACKGROUND: HIV-1 RNA plasma level is a key parameter for anti-viral treatment monitoring in HIV-1 infected individuals. Plasma stability and accurate measurement of clinical state is at risk when transporting from remote areas. Dried blood spot (DBS) testing can reduce this risk. OBJECTIVES: Determine the performance of NucliSENS EasyQ HIV-1 v2.0 for DBS. STUDY DESIGN: 100 HIV-1 negative, and 129 HIV-1 spiked blood specimens (2180 copies/ml) were used for diagnostic specificity and system robustness. Analytical performance was tested in the range 50-85,000,000 copies/ml. Clinical reactivity was measured with specimens obtained from 224 HIV-1 infected individuals. HIV-1 RNA stability was analyzed after applying several different storage conditions. RESULTS: Diagnostic specificity was 100% and system robustness was demonstrated by 100% detection rate without invalids. Limit of detection (95% detection rate) was 800 copies/ml. Linear results were obtained over the whole range tested. For clinical specimens, percentage positive results were comparable for DBS (57%) and plasma (58%). DBS quantification was on average 0.36log10 lower as compared to plasma. Specimen stability was demonstrated for 1 week at 55 degrees C/60% humidity, 3 weeks at 37 degrees C/80% humidity, 9 weeks at 37 degrees C/40% humidity, 3 months at -20 degrees C/70% humidity, 3 weeks at 4 degrees C/100% humidity, 9 months at room temperature (15-30 degrees C), and 9 weeks shipment simulation. CONCLUSION: Results obtained fully support the use of DBS for the NucliSENS EasyQ HIV-1 v2.0 assay. These findings are especially of importance in cases that plasma stability is currently at risk due to for example, long transport routes from remote areas under less controlled conditions.