Tuberculosis is a communicable disease caused by various strains of mycobacteria, most frequently Mycobacterium tuberculosis. The disease usually affects the lungs (pulmonary tuberculosis), but it can manifest anywhere outside the lungs as well (extrapulmonary tuberculosis). Tuberculosis spreads through person-to-person transmission, such as when individuals with pulmonary tuberculosis release bacteria through coughing. There are two main forms of TB—latent TB infection (LTBI), and active TB. People with LTBI are asymptomatic and cannot infect others; however, when those with LTBI develop active TB, they can then infect other people.

Tuberculosis remains a major global public health problem and one of the leading causes of death worldwide, with nearly 4,000 lives lost every day.^1,2 Over 10 million new cases are recorded each year. Additionally, a quarter of the global population is infected with latent tuberculosis, making LTBI a large reservoir for TB, which is why managing LBTI is critical for reducing and eliminating TB worldwide.

Treatment for TB involves taking a combination of drugs for several months, which is costly and frequently causes side effects. As a result, patients can find it difficult to adhere to treatment regimens. Unfortunately, incomplete or incorrectly administered treatment can lead to antimicrobial resistance. Multidrug resistant and extensively drug-resistant TB variants are more difficult and costly to treat, and they have higher mortality rates.

With prompt diagnosis and appropriate antibiotic treatment, most people with TB can be cured. However, diagnosis of TB is often delayed, due to multiple factors including a lack of knowledge or awareness of TB, non-specific symptoms, and inadequate access to healthcare. Additionally, diagnosing active TB and latent TB involve different approaches.

Methods for diagnosing active TB include bacteriological confirmation and clinical diagnosis. Bacteriological confirmation, including traditional microbial culture, lateral flow urine lipoarabinomannan (LF-LAM) assays, sputum smear microscopy, or rapid molecular tests, is a necessary step for identifying TB that is resistant to antimicrobials.

Methods for diagnosing latent TB include the tuberculin skin test (TST) and interferon-gamma release assays (IGRA). Adequate diagnosis and treatment of latent tuberculosis infection is one of the critical components of the World Health Organization’s End TB Strategy, essential to prevent the development of active tuberculosis disease and stop the spread of tuberculosis.

For active tuberculosis infections, our RAL STAINER helps standardize AFB (Acid-fast bacteria) staining for sputum smear microscopy. WHO guidelines recommend fluorescence as the reference method for staining and notes that Thiazine Red makes reading easier. The RAL STAINER and its reagents help ensure your lab meets these guidelines. 

Our VITEK^® MS and VITEK^® MS PRIME database includes Mycobacterium tuberculosis complex and is consistently expanding to add new emerging pathogens and clinically relevant species.

bioMérieux offers solutions for diagnosing both active and latent tuberculosis.