Efficiently Improving Laboratory Workflow with Continuous Sample Loading by Validating the COBAS 5800 for HIV and HCV Viral Loads

Abstract Introduction/Objective A regional veteran affairs medical center (VAMC) was using the COBAS AmpliPrep/COBAS Taqman (Roche, Basel Switzerland) with a throughput of 72 tests/8 hours without continuous loading capability. However, a newer cobas 5800 System (Roche, Basel Switzerland) was validated to allow for continuous loading with better parameters for workflow including 144 tests/per 8 hours with a capacity for continuous loading of samples without batching. As validation experiences between the two instruments is sparse in the literature, the validation is described. Methods/Case Report The validation process included a linearity study using 24 samples with levels (100, 600, 6,000, 60,000, 600,000, 2,000,000, and 6,000,000 copies/mL for HIV and 100, 300, 3,000, 30,000, 300,000, 3,000,000, and 30,000,000 copies/mL for HCV) across the analytical range, a precision study at a low (1,000 copies/mL) and high (100,000 copies/mL for HIV, 1,000,000 copies/ML for HCV) values of a triplicate run over 5 days, an accuracy study based on the precision study, a limit of detection study using 20 control samples at the limit of detection, control monitoring (high and low positive controls) over 9 runs, and a method correlation between the Cobas 5800 and the Cobas AmpliPrep/COBAS Taqman. Results (if a Case Study enter NA) The validation study resulted as expected. For the method correlation, the results were plotted and evaluated with an R2 of 0.937 (HIV from 91 samples) and 0.9646 (HCV from 74 samples). Linearity across the analytical range had an R2 of 0.9967 (HIV) and 0.9950 (HCV). All samples were detected at the limit of detection study. Both the accuracy and precision yielded expected results. The values from running the controls (high and low positive) over 9 runs remained within the expected range and within two standard deviations for all runs. Conclusion The COBAS 5800, which has improved capabilities compared to the COBAS AmpliPrep/COBAS Taqman, was validated for clinical use successfully.