Tuberculosis Diagnosis: Current, Ongoing, and Future Approaches

Abstract

Tuberculosis (TB) remains an impactful infectious disease, leading to millions of deaths every year. Mycobacterium tuberculosis causes the formation of granulomas, which will determine, through the host-pathogen relationship, if the infection will remain latent or evolve into active disease. Early TB diagnosis is life-saving, especially among immunocompromised individuals, and leads to proper treatment, preventing transmission. This review addresses different approaches to diagnosing TB, from traditional methods such as sputum smear microscopy to more advanced molecular techniques. Integrating these techniques, such as polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP), has significantly improved the sensitivity and specificity of M. tuberculosis identification. Additionally, exploring novel biomarkers and applying artificial intelligence in radiological imaging contribute to more accurate and rapid diagnosis. Furthermore, we discuss the challenges of existing diagnostic methods, including limitations in resource-limited settings and the emergence of drug-resistant strains. While the primary focus of this review is on TB diagnosis, we also briefly explore the challenges and strategies for diagnosing non-tuberculous mycobacteria (NTM). In conclusion, this review provides an overview of the current landscape of TB diagnostics, emphasizing the need for ongoing research and innovation. As the field evolves, it is crucial to ensure that these advancements are accessible and applicable in diverse healthcare settings to effectively combat tuberculosis worldwide.

Keywords: Mycobacterium tuberculosis; diagnostic techniques; molecular techniques; pulmonary tuberculosis diagnosis.

Figure 1

This figure illustrates relevant diagnostic techniques employed for pulmonary tuberculosis diagnosis. Sputum is collected and examined under a microscope for acid-fast bacilli (AFB). Chest radiography assesses lung abnormalities such as infiltrates, cavities, or pleural effusions. Molecular techniques detect the genetic material of MTBC using methods like NAATs, LAMP, MALDI-TOF MS, biosensors, and sequencing. Immunological tests, such as IGRAs, TST, and TBSTs, measure the body’s immunity in response to mycobacterial proteins. Culture involves growing the mycobacteria in a laboratory for identification and further antimicrobial susceptibility testing. These techniques collectively aid in the diagnosis of pulmonary tuberculosis. Created with BioRender.com.