Sethi Sunil, Sharma Shelly, Aggarwal Ashutosh N, Dhatwalia Sunil Kumar, Rana Rajesh, Yadav Rakesh
Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, 160012, India.
Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Infection. 2024 Dec;52(6):2207-2212. doi: 10.1007/s15010-024-02260-7. Epub 2024 May 6.
To assess the Xpert MTB/XDR assay's efficiency in promptly detecting resistance to isoniazid, fluoroquinolones, ethionamide, and second-line injectable drugs among tuberculosis (TB) patients.
From August 2020 to July 2021, TB suspected patient samples were enrolled at a tertiary care center for our study. We conducted mycobacterial culture, phenotypic DST using proportion method in liquid culture at WHO-recommended concentrations, and the line probe assay (LPA). Simultaneously, the Index test, Xpert MTB/XDR, was performed following the manufacturer's instructions.
Among 360 samples, 107 were excluded due to incomplete information. Resistance to isoniazid, levofloxacin and moxifloxacin was found in 45/251, 21/251 and 20/251 samples, respectively by phenotypic DST. The diagnostic accuracy of Index test, taking phenotypic DST as a reference standard, was 95.8%, 99.04%, and 99.05% for isoniazid, levofloxacin, and moxifloxacin, respectively. The Index test assay demonstrated a specificity of 99.1% for detecting SLID resistance, yielding a diagnostic accuracy of 99.2. Comparing the Index test with LPA revealed a significant enhancement in sensitivity for detecting isoniazid resistance (86.7% vs. 82.2%).
The Index test exhibited promising outcomes in identifying resistance to isoniazid and fluoroquinolones, surpassing the performance of the LPA. This could be valuable for promptly initiating treatment in cases of drug-resistant tuberculosis.
评估Xpert MTB/XDR检测法在快速检测结核病（TB）患者对异烟肼、氟喹诺酮类、乙硫异烟胺和二线注射用药物耐药性方面的效率。
2020年8月至2021年7月，在一家三级医疗中心纳入疑似结核病患者样本进行我们的研究。我们进行了分枝杆菌培养、使用WHO推荐浓度的液体培养比例法进行表型药物敏感性试验（DST）以及线性探针测定法（LPA）。同时，按照制造商的说明进行指标检测Xpert MTB/XDR。
在360份样本中，107份因信息不完整被排除。通过表型DST分别在45/251、21/251和20/251份样本中发现了对异烟肼、左氧氟沙星和莫西沙星的耐药性。以表型DST作为参考标准，指标检测对异烟肼、左氧氟沙星和莫西沙星的诊断准确性分别为95.8%、99.04%和99.05%。指标检测法在检测二线注射用药物耐药性方面显示出99.1%的特异性，诊断准确性为99.2%。将指标检测与LPA进行比较，发现检测异烟肼耐药性的敏感性有显著提高（86.7%对82.2%）。
指标检测在识别对异烟肼和氟喹诺酮类的耐药性方面显示出良好的结果，超过了LPA的性能。这对于耐药结核病病例的及时治疗可能具有重要价值。
