Center for Bio-design and Diagnostics, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, India.
Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.
PLoS One. 2019 Aug 13;14(8):e0220967. doi: 10.1371/journal.pone.0220967. eCollection 2019.
India has the highest burden of Tuberculosis (TB) and multidrug-resistant TB (MDR-TB) worldwide. Innovative technology is the need of the hour to identify these cases that remain either undiagnosed or inadequately diagnosed due to the unavailability of appropriate tools at primary healthcare settings. We developed and evaluated 3 kits, namely 'TB Detect' (containing BioFM-Filter device), 'TB Concentration and Transport' (containing Trans-Filter device) and 'TB DNA Extraction' kits. These kits enable bio-safe equipment-free concentration of sputum on filters and improved fluorescence microscopy at primary healthcare centres, ambient temperature transport of dried inactivated sputum filters to central laboratories and molecular detection of drug resistance by PCR and DNA sequencing (Mol-DST). In a 2-site evaluation (n = 1190 sputum specimens) on presumptive TB patients, BioFM-Filter smear exhibited a significant increase in positivity of 7% and 4% over ZN smear and LED-FM smear (p<0.05), respectively and an increment in smear grade status (1+ or 2+ to 3+) of 16% over ZN smear and 20% over LED-FM smear. The sensitivity of Mol-DST in presumptive MDR-TB and XDR-TB cases (n = 148) was 90% for Rifampicin (95% confidence interval [CI], 78-96%), 84% for Isoniazid (95% CI, 72-92%), 83% for Fluoroquinolones (95% CI, 66-93%) and 75% for Aminoglycosides (95% CI, 35-97%), using phenotypic DST as the reference standard. Test specificity was 88-93% and concordance was ~89-92% (κ value 0.8-0.9). The patient-friendly kits described here address several of the existing challenges and are designed to provide 'Universal Access' to rapid TB diagnosis, including drug-resistant disease. Their utility was demonstrated by application to sputum at 2 sites in India. Our findings pave the way for larger studies in different point-of-care settings, including high-density urban areas and remote geographical locations.
印度是全球结核病（TB）和耐多药结核病（MDR-TB）负担最重的国家。为了发现那些由于基层医疗保健机构缺乏适当工具而导致诊断不足或未确诊的病例，创新技术是当前的迫切需要。我们开发并评估了 3 种试剂盒，分别是“TB Detect”（包含 BioFM-过滤器设备）、“TB 浓缩和运输”（包含 Trans-Filter 设备）和“TB DNA 提取”试剂盒。这些试剂盒可在基层医疗保健中心实现无生物安全设备的痰液过滤浓缩和改良荧光显微镜检查，在常温下将干燥失活的痰滤器运输到中央实验室，并通过 PCR 和 DNA 测序（Mol-DST）进行耐药性分子检测。在对 1190 例疑似结核病患者的 2 个地点评估中（n = 1190 份痰液标本），BioFM-过滤器涂片的阳性率分别比 ZN 涂片和 LED-FM 涂片显著提高了 7%和 4%（p<0.05），并且涂片等级状态（1+或 2+至 3+）分别提高了 16%和 20%。在 148 例疑似耐多药结核病和广泛耐药结核病病例中，Mol-DST 的敏感性分别为利福平 90%（95%置信区间[CI]，78-96%）、异烟肼 84%（95% CI，72-92%）、氟喹诺酮类药物 83%（95% CI，66-93%）和氨基糖苷类药物 75%（95% CI，35-97%），以表型 DST 为参考标准。测试特异性为 88-93%，一致性约为 89-92%（κ 值 0.8-0.9）。这里描述的患者友好型试剂盒解决了一些现有挑战，并旨在提供“普遍获得”快速结核病诊断，包括耐药疾病。在印度的 2 个地点应用这些试剂盒，证明了其有效性。我们的发现为在不同的即时护理环境中开展更大规模的研究铺平了道路，包括高密度城市地区和偏远地理位置。
