折叠显微镜：其在国家疟疾控制项目中应用的诊断准确性与可行性

Foldscope: Diagnostic Accuracy and Feasibility of its Use in National Malaria Control Program.

作者信息

Gupta Sweta, Mathews Bijina John, Ghantaa Sai Nikhila, Amerneni Krishna Chaitanya, Karuna T, Pakhare Abhijit, Joshi Deepti, Khadanga Sagar

机构信息

Department of Microbiology, AIIMS, Bhopal, Madhya Pradesh, India.

Department of CFM, AIIMS, Bhopal, Madhya Pradesh, India.

出版信息

J Microsc Ultrastruct. 2021 May 24;10(3):114-117. doi: 10.4103/jmau.jmau_103_20. eCollection 2022 Jul-Sep.

DOI:10.4103/jmau.jmau_103_20

PMID:36504592

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9728086/

Abstract

BACKGROUND

Malaria has been an important public health all over the globe. Although conventional light microscopy is the gold standard of diagnosis, light microscopes are heavy, fragile, costly, and electricity dependent. Rapid diagnostic tests (RDTs) have become more popular but perform badly in temperate climate. This is because the RDT kits require maintenance of cold chain for its optimal use. In this regard, there is a recent interest in handheld malaria microscopy at the point of care in the field setting. Foldscopes are cheap, handy, nonfragile, and use mobile camera for illumination. The purpose of the study was to find whether foldscope can be used in the national vector borne disease control program (NVBDCP) in India.

METHODS

Ten laboratory technicians were trained in identifying malaria parasites using foldscope and their mobiles. Later, they were provided with unassembled foldscope to document their test results for the preidentified malaria slides. The blood smears were stained as per the protocol of NVBDCP. The report of the index test (foldscope microscopy) was compared with the reference test (conventional microscopy).

RESULTS

The sensitivity and specificity of the index test was found to be 13.3% (6.257-26.18), specificity of 97.78% (88.43-99.61), positive predictive value 85.71% (48.69-97.43), and negative predictive value 53.01% (42.38-63.38). The devise failure rate and test failure rate were 20% and 11.7%. The kappa agreement between the index and reference microscopy was only 11% and the McNemar < 0.01.

CONCLUSION

The ×400 foldscope at its present magnification and illumination cannot be utilized in the field under NVBDCP.

摘要

背景

疟疾一直是全球重要的公共卫生问题。尽管传统光学显微镜是诊断的金标准，但光学显微镜笨重、易碎、成本高且依赖电力。快速诊断检测（RDTs）越来越受欢迎，但在温带气候下表现不佳。这是因为RDT试剂盒需要冷链保存以实现最佳使用。在这方面，近期人们对现场即时护理时的手持式疟疾显微镜产生了兴趣。折叠显微镜价格便宜、便于携带、不易损坏，且使用手机摄像头进行照明。本研究的目的是探究折叠显微镜能否用于印度国家媒介传播疾病控制项目（NVBDCP）。

方法

对十名实验室技术人员进行培训，使其使用折叠显微镜及其手机识别疟原虫。之后，为他们提供未组装的折叠显微镜，用于记录预先确定的疟疾玻片的检测结果。血涂片按照NVBDCP的方案进行染色。将指标检测（折叠显微镜检查）的报告与参考检测（传统显微镜检查）进行比较。

结果

发现指标检测的灵敏度为13.3%（6.257 - 26.18），特异性为97.78%（88.43 - 99.61），阳性预测值为85.71%（48.69 - 97.43），阴性预测值为53.01%（42.38 - 63.38）。设备故障率和检测故障率分别为20%和11.7%。指标显微镜检查与参考显微镜检查之间的kappa一致性仅为11%，McNemar检验<0.01。