[Molecular diagnosis of tuberculosis]

Area of Science:

• Microbiology and Infectious Diseases
• Molecular Diagnostics
• Genomic Medicine

Background:

• Tuberculosis (TB) diagnosis is often delayed due to the slow growth of Mycobacterium tuberculosis.
• Phenotypic diagnostic methods are time-consuming, impacting timely treatment initiation.
• Molecular biology offers rapid detection of M. tuberculosis complex and drug resistance.

Purpose of the Study:

• To review the impact of molecular diagnostics on tuberculosis and drug resistance detection.
• To highlight the advantages and limitations of current molecular tests.
• To discuss the potential of emerging genomic sequencing technologies.

Main Methods:

• Review of molecular diagnostic techniques for tuberculosis, including Xpert® MTB/RIF.
• Analysis of performance characteristics of molecular tests for drug resistance.
• Evaluation of the role of acid-fast bacilli microscopy in molecular test performance.

Main Results:

• Molecular tests like Xpert® MTB/RIF drastically reduce diagnostic time for TB and rifampicin resistance.
• Performance of molecular tests is compromised by negative microscopy results.
• Current resistance detection assays target known mutations, with varying drug-specific performance.

Conclusions:

• Molecular biology has revolutionized TB diagnosis and resistance testing, but remains a screening tool.
• Genomic sequencing presents a promising future for comprehensive TB diagnostics, pending workflow integration and standardization.
• Clinical suspicion remains critical for appropriate molecular test utilization; phenotypic methods are still essential for confirmation.