Feliciano Cinara Silva, Menon Lucas José Bazzo, Anselmo Livia Maria Pala, Dippenaar Anzaan, Warren Robin Mark, Silva Wilson Araújo, Bollela Valdes Roberto
Dept of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo (FMRP-USP), São Paulo, Brazil.
DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Stellenbosch, South Africa.
ERJ Open Res. 2019 Aug 5;5(3). doi: 10.1183/23120541.00043-2019. eCollection 2019 Jul.
Effective treatment of tuberculosis (TB) remains a serious public health problem in many countries, including Brazil, especially when considering drug-resistant disease. Xpert MTB/RIF has been implemented in many countries to reduce the time to TB diagnosis and to rapidly detect rifampicin resistance. The study aimed to describe and evaluate Xpert MTB/RIF performance in diagnosing pulmonary TB and rifampicin resistance in a tertiary healthcare facility in Brazil. A cross-sectional study was performed, which included all isolates of confirmed pulmonary TB patients from 2015 to 2018. Both Xpert MTB/RIF and GenoType MTBDR assays were performed to detect rifampicin and isoniazid resistance. In addition, isolates with detected resistance to rifampicin and/or isoniazid were analysed by phenotypic testing using MGIT-960 SIRE kit and whole-genome sequencing (WGS) using Illumina MiSeq Sequencing System. 2148 respiratory specimens tested with Xpert MTB/RIF were included: n=1556 sputum, n=348 bronchoalveolar lavage and n=244 gastric washing. The overall Xpert MTB/RIF sensitivity in sputum was 94% and the overall specificity was 98%. The negative predictive value in sputum of all the patients was 99% with a positive predictive value of 89%. The concordance between Xpert MTB/RIF and phenotypic susceptibility test was 94.1%, while its concordance with WGS was 78.9%. Xpert MTB/RIF is a rapid and accurate diagnostic strategy for pulmonary TB, which can contribute to improvement in TB control. However, detection of rifampicin resistance might be associated with false-positive results.
在包括巴西在内的许多国家，结核病（TB）的有效治疗仍是一个严重的公共卫生问题，尤其是考虑到耐药性疾病时。许多国家已采用Xpert MTB/RIF来缩短结核病诊断时间并快速检测利福平耐药性。本研究旨在描述和评估Xpert MTB/RIF在巴西一家三级医疗机构中诊断肺结核和利福平耐药性的性能。进行了一项横断面研究，纳入了2015年至2018年所有确诊肺结核患者的分离株。同时采用Xpert MTB/RIF和GenoType MTBDR检测法来检测利福平和异烟肼耐药性。此外，对检测出对利福平和/或异烟肼耐药的分离株，使用MGIT-960 SIRE试剂盒进行表型检测，并使用Illumina MiSeq测序系统进行全基因组测序（WGS）。纳入了2148份经Xpert MTB/RIF检测的呼吸道标本：n = 1556份痰液标本、n = 348份支气管肺泡灌洗标本和n = 244份洗胃标本。Xpert MTB/RIF在痰液中的总体敏感性为94%，总体特异性为98%。所有患者痰液检测的阴性预测值为99%，阳性预测值为89%。Xpert MTB/RIF与表型药敏试验的一致性为94.1%，与WGS的一致性为78.9%。Xpert MTB/RIF是一种快速、准确的肺结核诊断策略，有助于改善结核病防控。然而，利福平耐药性检测可能会出现假阳性结果。
