Role of a GenoType MTBDRplus line probe assay in early detection of multidrug-resistant tuberculosis at a Brazilian reference center

Resistance to Mycobacterium tuberculosis is a reality worldwide, and its diagnosis continues to be difficult and time consuming. To face this challenge, the World Health Organization has recommended the use of rapid molecular tests. We evaluated the routine use (once a week) of a line probe assay (Genotype MTBDRplus) for early diagnosis of resistance and for assessment of the main related risk factors over 2 years. A total of 170 samples were tested: 15 (8.8%) were resistant, and multidrug resistance was detected in 10 (5.9%). The sensitivity profile took 3 weeks (2 weeks for culture and 1 week for rapid testing). Previous treatment for tuberculosis and the persistence of positive acid-fast smears after 4 months of supervised treatment were the major risk factors observed. The use of molecular tests enabled early diagnosis of drug-resistant bacilli and led to appropriate treatment of the disease. This information has the potential to interrupt the transmission chain of resistant M. tuberculosis.

结核分枝杆菌（Mycobacterium tuberculosis）耐药已成为全球性公共卫生现状，其诊断工作仍面临难度高、耗时长的困境。为应对这一挑战，世界卫生组织（World Health Organization, WHO）推荐采用快速分子检测方案。本研究针对为期2年的临床周期，评估了线探针检测（line probe assay，Genotype MTBDRplus）每周1次的常规应用方案，用于结核分枝杆菌耐药性的早期诊断以及相关主要危险因素的筛查。本次研究共检测170份样本：其中15份（8.8%）呈现耐药性，10份（5.9%）检出耐多药结核分枝杆菌。该检测的全流程周转时长为3周，其中培养阶段耗时2周，快速检测环节耗时1周。本研究观察到的主要危险因素包括：既往结核治疗史，以及接受督导治疗4个月后抗酸涂片（acid-fast smears）仍持续呈阳性。该分子检测技术的应用实现了耐药结核分枝杆菌的早期诊断，并确保患者接受了规范恰当的治疗。该研究结果有望阻断耐药结核分枝杆菌的传播链条。