Burnet Institute, Melbourne, Australia
Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.
J Clin Microbiol. 2019 Mar 28;57(4). doi: 10.1128/JCM.01683-18. Print 2019 Apr.
HIV viral load (VL) testing is the recommended method for monitoring the response of people living with HIV and receiving antiretroviral therapy (ART). The availability of standard plasma VL testing in low- and middle-income countries (LMICs), and access to this testing, are limited by the need to use fresh plasma. Good specimen collection methods for HIV VL testing that are applicable to resource-constrained settings are needed. We assessed the diagnostic performance of the filtered dried plasma spot (FDPS), created using the newly developed, instrument-free VLPlasma device, in identifying treatment failure at a VL threshold of 1,000 copies/ml in fresh plasma. Performance was compared with that of the conventional dried blood spot (DBS). Venous blood samples from 201 people living with HIV and attending an infectious disease clinic in Malaysia were collected, and HIV VL was quantified using fresh plasma (the reference standard), FDPS, and DBS specimens. VL testing was done using the Roche Cobas AmpliPrep/Cobas TaqMan v2.0 assay. At a threshold of 1,000 copies/ml, the diagnostic performance of the FDPS was superior (sensitivity, 100% [95% confidence interval {CI}, 89.1 to 100%]; specificity, 100% [95% CI, 97.8 to 100%]) to that of the DBS (sensitivity, 100% [95% CI, 89.4 to 100%]; specificity, 36.8% [95% CI, 29.4 to 44.7%]) ( < 0.001). A stronger correlation was observed between the FDPS VL and the plasma VL ( = 0.94; < 0.001) than between the DBS VL and the plasma VL ( = 0.85; < 0.001). The mean difference in VL measures between the FDPS and plasma (plasma VL minus FDPS VL) was 0.127 log copies/ml (standard deviation [SD], 0.32), in contrast to -0.95 log copies/ml (SD, 0.84) between the DBS and plasma. HIV VL measurement using the FDPS outperformed that with the DBS in identifying treatment failure at a threshold of 1,000 copies/ml and compared well with the quantification of VL in plasma. The FDPS can be an attractive alternative to fresh plasma for improving access to HIV VL monitoring among people living with HIV on ART in LMICs.
HIV 病毒载量 (VL) 检测是监测接受抗逆转录病毒治疗 (ART) 的 HIV 感染者治疗反应的推荐方法。在中低收入国家 (LMICs)，标准血浆 VL 检测的可用性和获得该检测的机会受到需要使用新鲜血浆的限制。需要开发适用于资源有限环境的良好 HIV VL 检测标本采集方法。我们评估了使用新开发的无仪器 VLPlasma 设备创建的过滤干燥血浆斑（FDPS）在识别 1000 拷贝/ml 阈值下治疗失败的诊断性能，在新鲜血浆中。性能与传统的干燥血斑（DBS）进行了比较。从马来西亚一家传染病诊所就诊的 201 名 HIV 感染者采集静脉血样本，并使用新鲜血浆（参考标准）、FDPS 和 DBS 标本定量检测 HIV VL。VL 检测使用罗氏 Cobas AmpliPrep/Cobas TaqMan v2.0 检测进行。在 1000 拷贝/ml 的阈值下，FDPS 的诊断性能优于 DBS（灵敏度，100%[95%置信区间{CI}，89.1%至 100%]；特异性，100%[95%CI，97.8%至 100%]）（ < 0.001）。FDPS VL 与血浆 VL 之间的相关性强于 DBS VL 与血浆 VL 之间的相关性（ = 0.94； < 0.001）（ = 0.85； < 0.001）。FDPS 与血浆 VL 之间 VL 测量值的平均差异（血浆 VL 减去 FDPS VL）为 0.127 log 拷贝/ml（标准差 [SD]，0.32），而 DBS 与血浆 VL 之间的差异为 -0.95 log 拷贝/ml（SD，0.84）。在 1000 拷贝/ml 的阈值下，FDPS 比 DBS 更能识别治疗失败，与血浆中 VL 的定量相比表现良好。在 LMICs 中，FDPS 可以替代新鲜血浆，为接受 ART 的 HIV 感染者提供更好的 HIV VL 监测机会。
