PDF(Pubmed)
Abstract：
The PATHFAST TB LAM Ag assay is based on a chemiluminescent enzyme immunoassay to quantify lipoarabinomannan (LAM) in sputum within 1 h, and was developed as an alternative to conventional culture methods for monitoring tuberculosis (TB) treatment. This study aimed to evaluate the analytical performance and initial clinical feasibility of using five Mycobacterium tuberculosis variants, 178 non-tuberculous mycobacteria (NTM), 34 upper respiratory and oral cavity microorganisms, 100 sputum specimens from untreated patients, and potential interfering substances, including 27 drugs. The results reveled a single-site repeatability coefficient of variation (CV) of 5.2%-7.0%, and a multi-site reproducibility CV of 7.1%-8.4%. The limit of blank, limit of detection, and limit of quantification were 3.03 pg/mL, 6.67 pg/mL, and 7.44 pg/mL, respectively. Linearity was observed over the analytical measurement range (10.0 pg/mL-50,000 pg/mL), and no hook effect was observed. The assay tended to cross-react with slow-growing NTMs, but not with common upper respiratory and oral cavity microorganisms, except Nocardia asteroides, Nocardia farcinica, and Tsukamurella paurometabola. No interference was observed in the presence of mucin, blood, or major anti-TB, anti-HIV, and anti-pneumonia drugs. Regarding clinical performance, the assay had a sensitivity of 88.8% (95% CI: 80.0%-94.0%) and specificity of 100.0% (95% CI: 83.9%-100.0%) using mycobacterial culture as the reference standard, and a correlation (Spearman\'s r = -0.770) was observed between LAM concentration and time to detection of culture. These findings show, for the first time, that the PATHFAST TB LAM Ag assay has potential value for monitoring TB treatment.
摘要：
PATHFASTTBLAMAg测定基于化学发光酶免疫测定，可在1小时内定量痰中的脂阿拉伯甘露聚糖（LAM），并被开发为监测结核病（TB）治疗的常规培养方法的替代方法。本研究旨在评估使用五种结核分枝杆菌变体的分析性能和初始临床可行性，178个非结核分枝杆菌（NTM），34上呼吸道和口腔微生物，来自未经治疗的患者的100个痰标本，和潜在的干扰物质，包括27种药物。结果表明,单位点重复性变异系数(CV)为5.2%-7.0%,多位点可重复性CV为7.1%-8.4%。空白的极限，检测限，定量限为3.03pg/mL，6.67pg/mL,和7.44pg/mL，分别。在分析测量范围（10.0pg/mL-50,000pg/mL）内观察到线性。并且没有观察到钩效应。该测定法倾向于与缓慢增长的NTM交叉反应，但没有常见的上呼吸道和口腔微生物，除了诺卡氏菌小行星,诺卡氏菌,和竹子。在粘蛋白的存在下没有观察到干扰，血,或主要的抗结核药，抗艾滋病毒，和抗肺炎药物。关于临床表现，以分枝杆菌培养为参考标准，该测定法的灵敏度为88.8%(95%CI:80.0%-94.0%)，特异性为100.0%(95%CI:83.9%-100.0%)，LAM浓度与培养检测时间之间存在相关性（Spearman\'sr=-0.770）。这些发现表明,第一次,PATHFASTTBLAMAg测定对监测TB治疗具有潜在价值。
