The World Health Organization (WHO) has released updated guidelines for the rapid diagnosis of tuberculosis (TB), emphasizing the utilization of targeted next-generation sequencing (NGS) tests for detecting drug-resistant TB strains. These guidelines advocate for the use of NGS on respiratory samples in individuals with confirmed pulmonary TB to diagnose resistance to key drugs such as rifampicin, isoniazid, fluoroquinolones, pyrazinamide, and ethambutol, surpassing traditional culture-based methods.
Three specific NGS tests have been highlighted: Deeplex Myc-TB from Genoscreen in France; AmPORE-TB from Oxford Nanopore Diagnostics in the UK; and Tbseq from Hangzhou ShengTing Medical Technology in China. The WHO stresses the need for continuous improvement in these tests, ensuring they meet stringent requirements before clinical use. Additionally, the guidelines endorse other molecular technologies like nucleic acid amplification tests (NAATs) for TB detection and resistance profiling, lateral flow antigen detection tests, and line-probe assays.
Accompanying the guidelines is a comprehensive operational handbook providing detailed instructions for laboratory personnel, clinicians, and stakeholders on implementing targeted NGS tests. This includes protocols, algorithms, and steps for scaling up these tests effectively. Furthermore, the WHO has launched a TB sequencing portal in collaboration with FIND and Unitaid, housing over 56,000 sequences and serving as a robust knowledgebase for Mycobacterium tuberculosis. The portal offers a dashboard for visualizing data from the WHO mutation catalog, facilitating the exploration of mutation frequencies and their correlation with drug resistance.
Tereza Kasaeva, director of WHO’s Global TB Programme, underscores the importance of advancing diagnostic options for drug-resistant TB, highlighting manufacturer engagement and research as pivotal in generating new evidence. The aim is to ensure equitable access to accurate and rapid diagnostic technologies, ultimately bolstering efforts to prevent and eradicate TB globally.