Rutstein Sarah E, Kamwendo Deborah, Lugali Lebah, Thengolose Isaac, Tegha Gerald, Fiscus Susan A, Nelson Julie A E, Hosseinipour Mina C, Sarr Abdoulaye, Gupta Sundeep, Chimbwandira Frank, Mwenda Reuben, Mataya Ronald
Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
UNC Project, Lilongwe, Malawi.
J Clin Virol. 2014 Aug;60(4):392-8. doi: 10.1016/j.jcv.2014.05.005. Epub 2014 May 22.
Viral suppression is a key indicator of antiretroviral therapy (ART) response among HIV-infected patients. Dried blood spots (DBS) are an appealing alternative to conventional plasma-based virologic testing, improving access to monitoring in resource-limited settings. However, validity of DBS obtained from fingerstick in field settings remains unknown.
Investigate feasibility and accuracy of DBS vs plasma collected by healthcare workers in real-world settings of remote hospitals in Malawi. Compare venous DBS to fingerstick DBS for identifying treatment failure.
We recruited patients from ART clinics at two district hospitals in Malawi, collecting plasma, venous DBS (vDBS), and fingerstick DBS (fsDBS) cards for the first 149 patients, and vDBS and fsDBS only for the subsequent 398 patients. Specimens were tested using Abbott RealTime HIV-1 Assay (lower detection limit 40 copies/ml (plasma) and 550 copies/ml (DBS)).
21/149 (14.1%) had detectable viremia (>1.6 log copies/ml), 13 of which were detectable for plasma, vDBS, and fsDBS. Linear regression demonstrated high correlation for plasma vs. DBS (vDBS: β=1.19, R(2)=0.93 (p<0.0001); fsDBS β=1.20, R(2)=0.90 (p<0.0001)) and vDBS vs. fsDBS (β=0.88, R(2)=0.73, (p<0.0001)). Mean difference between plasma and vDBS was 1.1 log copies/ml [SD: 0.27] and plasma and fsDBS 1.1 log copies/ml [SD: 0.31]. At 5000 copies/ml, sensitivity was 100%, and specificity was 98.6% and 97.8% for vDBS and fsDBS, respectively, compared to plasma.
DBS from venipuncture and fingerstick perform well at the failure threshold of 5000 copies/ml. Fingerstick specimen source may improve access to virologic treatment monitoring in resource-limited settings given task-shifting in high-volume, low-resource facilities.
病毒抑制是艾滋病毒感染患者抗逆转录病毒治疗（ART）反应的关键指标。干血斑（DBS）是传统基于血浆的病毒学检测的一种有吸引力的替代方法，可改善资源有限环境下的监测途径。然而，在现场环境中通过手指采血获得的干血斑的有效性仍不清楚。
在马拉维偏远医院的实际环境中，调查医护人员采集的干血斑与血浆相比的可行性和准确性。比较静脉干血斑和手指采血干血斑用于识别治疗失败的情况。
我们从马拉维两家地区医院的抗逆转录病毒治疗诊所招募患者，为前149名患者采集血浆、静脉干血斑（vDBS）和手指采血干血斑（fsDBS）卡片，为随后的398名患者仅采集vDBS和fsDBS。使用雅培实时HIV-1检测法（血浆检测下限为40拷贝/毫升，干血斑检测下限为550拷贝/毫升）对样本进行检测。
21/149（14.1%）患者可检测到病毒血症（>1.6 log拷贝/毫升），其中13例血浆、vDBS和fsDBS均可检测到。线性回归显示血浆与干血斑之间具有高度相关性（vDBS：β = 1.19，R² = 0.93（p < 0.0001）；fsDBS β = 1.20，R² = 0.90（p < 0.0001））以及vDBS与fsDBS之间具有高度相关性（β = 0.88，R² = 0.73，（p < 0.0001））。血浆与vDBS之间的平均差异为1.1 log拷贝/毫升[标准差：0.27]；血浆与fsDBS之间的平均差异为1.1 log拷贝/毫升[标准差：0.31]。在5000拷贝/毫升时，与血浆相比，vDBS的敏感性为100%，特异性为98.6%；fsDBS的敏感性为100%，特异性为97.8%。
静脉穿刺和手指采血获得的干血斑在5000拷贝/毫升的失败阈值下表现良好。鉴于在高工作量、低资源设施中任务转移，手指采血样本来源可能改善资源有限环境下的病毒学治疗监测途径。
