Comparison of the Abbott realtime human immunodeficiency virus type 1 (HIV-1) assay to the Cobas AmpliPrep/Cobas TaqMan HIV-1 test: workflow, reliability, and direct costs.

The Abbott RealTime human immunodeficiency virus type 1 (HIV-1) assay (ART) and the Cobas AmpliPrep/Cobas TaqMan HIV-1 test (CTM) are commercially available assays for quantification of HIV-1 RNA in plasma. We evaluated performance characteristics, workflow, throughput, reliability, and direct costs of these assays. Both assays yielded good correlation of quantitative results (r = 0.95) among clinical specimens, with a mean difference of -0.34 log(10) copies/ml. Testing of healthy donor plasma specimens yielded "target not detected" results by ART, with "HIV-1 RNA detected, <40 copies/ml" results for 3.3% (3 of 90 samples) of these specimens by CTM. Both the m2000sp/m2000rt (ART) and docked CAP/CTM96 (CTM) instrument systems were capable of operating with continuous, uninterrupted workflow. When daily maintenance and cleaning were included, ART and CTM run durations (5 h 52 min and 6 h 4 min, respectively) and hands-on times (53 min and 46 min, respectively) were similar for a run batch size of 24. While ART was more flexible in terms of run batch size, CTM required fewer user interventions and consistently produced higher specimen throughput rates at 8, 16, and 24 h. Assay run failure rates were 6.3% (1 of 16 runs) and 4.2% (1 of 24 runs) for ART and CTM, respectively (P = 1.000), with invalid specimen result rates of 1.0% (5 of 495 specimens) and 2.8% (11 of 399 specimens), respectively (P = 0.073). Direct reagent and consumable costs for each assay were comparable (difference of <10%). In selecting an assay for implementation, laboratories should consider how various assay and instrument features might impact laboratory operation and patient care.

Impact of the COBAS AmpliPrep/COBAS AMPLICOR HIV-1 MONITOR Test, Version 1.5, on clinical laboratory operations.

The COBAS AmpliPrep/COBAS AMPLICOR HIV-1 MONITOR Test, version 1.5 (CAP/CA), and the COBAS AMPLICOR HIV-1 MONITOR Test, version 1.5, were compared. CAP/CA reduced and consolidated labor while modestly increasing assay throughput without increased failure rates or direct costs, regardless of batch size and assay format.

Detection of HIV-1 proviral DNA with the AMPLICOR HIV-1 DNA Test, version 1.5, following sample processing by the MagNA Pure LC instrument.

BACKGROUND: The AMPLICOR HIV-1 DNA Test, version 1.5 (AMP HIV-1 DNA 1.5), is a new commercially available PCR assay for the detection of human immunodeficiency virus type 1 (HIV-1) proviral DNA in human whole blood. OBJECTIVE: This study evaluates the performance characteristics of the assay following automated sample processing by the MagNA Pure LC instrument (MP). STUDY DESIGN: Analytical sensitivity and reproducibility were assessed by testing replicate HIV-1 DNA dilution panels over 5 days. Clinical sensitivity and specificity were studied among 28 HIV-1 DNA-positive clinical specimens, 60 specimens from healthy blood donors, and 63 specimens from HIV-1-seropositive patients with HIV-1 RNA plasma levels ranging from <50 to >100,000 copies/mL. RESULTS: Following MP sample processing, the assay yielded an analytical sensitivity (95% detection rate) of 66.3 copies/mL (95% CI, 50.7-106.8), with clinical sensitivity and specificity of 100%. CONCLUSIONS: MP is a reliable, labor-saving platform capable of processing specimens for AMP HIV-1 DNA 1.5. When combined with MP sample processing, AMP HIV-1 DNA 1.5 is a sensitive and reproducible assay for the detection of HIV-1 DNA in clinical whole blood specimens. However, the current AMP HIV-1 DNA 1.5 kit configuration may result in inefficient utilization of reagents.