Meta-Analysis Confirms Strong Performance of Xpert HIV-1 Viral Load at Point of Care
A systematic review and meta-analysis of 13 studies found that the Cepheid Xpert HIV-1 Viral Load assay achieves a pooled Pearson correlation of 0.94 and Bland-Altman agreement within 0.35 log copies/mL compared to reference methods. The platform leverages existing GeneXpert infrastructure already deployed for TB diagnosis, making it particularly attractive for resource-constrained settings where near-patient viral load monitoring is most needed.
The original study
Performance of the Xpert HIV-1 Viral Load Assay: a Systematic Review and Meta-analysis.
- Authors
- Nash M, Huddart S, Badar S, Baliga S, Saravu K, Pai M
- Journal
- Journal of clinical microbiology
- Type
- Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Systematic Review
- PMID
- 29386266
Original abstract
Viral load (VL) is the preferred treatment-monitoring approach for HIV-positive patients. However, more rapid, near-patient, and low-complexity assays are needed to scale up VL testing. The Xpert HIV-1 VL assay (Cepheid, Sunnyvale, CA) is a new, automated molecular test, and it can leverage the GeneXpert systems that are being used widely for tuberculosis diagnosis. We systematically reviewed the evidence on the performance of this new tool in comparison to established reference standards. A total of 12 articles (13 studies) in which HIV patient VLs were compared between Xpert HIV VL assay and a reference standard VL assay were identified. Study quality was generally high, but substantial variability was observed in the number and type of agreement measures reported. Correlation coefficients between Xpert and reference assays were high, with a pooled Pearson correlation (n = 8) of 0.94 (95% confidence interval [CI], 0.89, 0.97) and Spearman correlation (n = 3) of 0.96 (95% CI, 0.86, 0.99). Bland-Altman metrics (n = 11) all were within 0.35 log copies/ml of perfect agreement. Overall, Xpert HIV-1 VL performed well compared to current reference tests. The minimal training and infrastructure requirements for the Xpert HIV-1 VL assay make it attractive for use in resource-constrained settings, where point-of-care VL testing is most needed.