Brandao Angela Pires, Ferreira Fabiane Maria de Almeida, Simeao Fernanda Cristina Dos Santos, Ferrazoli Lucilaine, Chimara Erica, de Oliveira Rosângela Siqueira, Pinhata Juliana Maira Watanabe
Núcleo de Tuberculose e Micobacterioses, Centro de Bacteriologia, Instituto Adolfo Lutz (IAL), São Paulo, Brazil.
Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil.
J Clin Microbiol. 2025 Sep 23:e0091225. doi: 10.1128/jcm.00912-25.
Drug-resistant tuberculosis (TB) remains a primary global health concern. Multidrug-resistant TB is defined by resistance to at least rifampicin (RIF) and isoniazid (INH), the two key drugs used in TB treatment. The BD MAX Multi-Drug Resistant Tuberculosis (BD MAX) assay is a fully automated real-time PCR platform recommended by the World Health Organization for the initial diagnosis of TB and RIF and INH resistance (RIF-R and INH-R) directly from pulmonary clinical samples. This study aimed to assess the off-label performance of BD MAX in clinical complex (MTBC) isolates under routine laboratory conditions. The assay was first validated using non-tuberculous mycobacteria (NTM) and MTBC isolates with known mutations. For real-world validation, it was compared to the GenoType MTBDR by testing 1,440 clinical isolates prospectively. The BD MAX assay correctly excluded MTBC from all NTM cultures. Among MTBC isolates with known mutations, it identified 19 of 20 RIF-R isolates and 14 of 15 INH-R isolates. In prospective testing, BD MAX achieved 99.6% sensitivity (1,403/1,409), 96.8% specificity (30/31), and 99.5% overall accuracy (1,433/1,440) for MTBC detection. For drug resistance detection, it showed 95.2% (40/42) concordance for RIF, 96.8% (30/31) for INH, and 81.3% (13/16) for MDR when compared to MTBDR. Discrepancies between MTBDR and BD MAX included heteroresistant cases and unreportable resistance results by BD MAX due to infrequent mutations or low bacterial load. Overall, this study confirms BD MAX as an accurate and reliable tool for MTBC detection and drug resistance profiling in clinical isolates in high-volume TB laboratories.IMPORTANCEThis study highlights the importance of the BD MAX Multi-Drug Resistant Tuberculosis assay (BD MAX) applied in clinical isolates for the detection of multidrug-resistant tuberculosis (MDR-TB), i.e., resistance to rifampicin and isoniazid. TB is a global health issue, and drug-resistant TB makes treatment more difficult, favoring transmission and disease amplification. The BD MAX platform offers a faster and more automated way to detect TB and drug resistance. The study showed that BD MAX, applied off-label in clinical isolates, accurately identified TB and resistance to rifampicin and isoniazid, with results comparable to those of the widely used line probe assay. This is significant in a high-volume laboratory because it is more straightforward and more rapid than the line probe assay. BD MAX showed some limitations, especially in detecting rare mutations and in cases of low bacterial levels. Overall, this tool could improve TB care, especially in high-volume laboratories.
耐多药结核病仍然是全球主要的健康问题。耐多药结核病的定义是对至少利福平（RIF）和异烟肼（INH）耐药，这两种药物是结核病治疗中的关键药物。BD MAX 多药耐药结核病检测（BD MAX）是世界卫生组织推荐的一种全自动实时聚合酶链反应平台，可直接从肺部临床样本中对结核病以及利福平和异烟肼耐药性（利福平耐药和异烟肼耐药）进行初步诊断。本研究旨在评估 BD MAX 在常规实验室条件下对临床复杂结核分枝杆菌复合群（MTBC）分离株的超说明书使用性能。该检测首先使用非结核分枝杆菌（NTM）和具有已知突变的 MTBC 分离株进行验证。为进行实际验证，通过前瞻性检测 1440 株临床分离株，将其与 GenoType MTBDR 进行比较。BD MAX 检测正确地从所有 NTM 培养物中排除了 MTBC。在具有已知突变的 MTBC 分离株中，它鉴定出 20 株利福平耐药分离株中的 19 株以及 15 株异烟肼耐药分离株中的 14 株。在前瞻性检测中，BD MAX 对 MTBC 检测的灵敏度达到 99.6%（1403/1409），特异性为 96.8%（30/31），总体准确率为 99.5%（1433/1440）。对于耐药性检测，与 MTBDR 相比，其利福平的一致性为 95.2%（40/42），异烟肼为 96.8%（30/31），耐多药为 81.3%（13/16）。MTBDR 和 BD MAX 之间的差异包括异质性耐药病例以及由于罕见突变或细菌载量低导致 BD MAX 无法报告耐药结果的情况。总体而言，本研究证实 BD MAX 是大容量结核病实验室中用于临床分离株 MTBC 检测和耐药性分析的准确可靠工具。重要性本研究强调了将 BD MAX 多药耐药结核病检测（BD MAX）应用于临床分离株以检测耐多药结核病（MDR - TB）（即对利福平和异烟肼耐药）的重要性。结核病是一个全球健康问题，耐多药结核病使治疗更加困难，助长了传播和疾病扩散。BD MAX 平台提供了一种更快且更自动化的方法来检测结核病和耐药性。该研究表明，BD MAX 在临床分离株中超说明书使用时，能够准确识别结核病以及对利福平和异烟肼的耐药性，其结果与广泛使用的线性探针检测法相当。这在大容量实验室中具有重要意义，因为它比线性探针检测法更直接、更快速。BD MAX 显示出一些局限性，尤其是在检测罕见突变和细菌水平较低的情况下。总体而言，该工具可改善结核病护理，特别是在大容量实验室中。
