Journal of Medical Diagnostic Methods
Open Access

Comprehension Tuberculosis Diagnosis: A Comprehensive Guide

Sabina Prajwal^{* *}Correspondence: Sabina Prajwal, Department of Medicine, Capital Medical University of Beijing, Beijing, China, Email:

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Description

Tuberculosis (TB) remains one of the most significant global health challenges, with millions of new cases and deaths each year. Accurate and timely diagnosis is critical in controlling the spread of TB, a bacterial infection primarily affecting the lungs. This article provides an overview of TB diagnosis, including the methods used, challenges faced, and advancements in diagnostic techniques. Tuberculosis is caused by the bacterium Mycobacterium tuberculosis. It spreads through the air when an infected person coughs or sneezes. TB can affect various organs, but pulmonary TB, which affects the lungs, is the most common and contagious form. Symptoms of pulmonary TB include persistent cough, chest pain, fever, night sweats, and weight loss. The diagnostic process typically begins with a detailed medical history and physical examination. Health professionals ask about symptoms, potential exposure to TB, and any previous TB infections or treatments. A physical examination helps identify signs of TB, such as abnormal lung sounds. The Tuberculin Skin Test, also known as the Monteux test, is a widely used diagnostic tool. It involves injecting a small amount of Purified Protein Derivative (PPD) under the skin. After 48-72 hours, the test site is examined for a reaction.

A significant induration indicates a possible TB infection. However, the Tuberculin Skin Tests (TST) cannot distinguish between latent TB infection and active TB disease, and false positives or negatives can occur, particularly in individuals who have had previous TB or are immunocompromised. Interferon- Gamma Release Assay are blood tests that measure the immune response to specific TB antigens. They are more specific than the TST and are particularly useful in people who have had the Bacillus Calmette Guerin vaccine or are unlikely to return for

TST reading. These tests are generally more accurate but are more expensive and less widely available than the TST. A chest Xray is an essential tool in the diagnosis of pulmonary TB. It helps visualize lung abnormalities such as cavitary lesions or nodules that are characteristic of TB.

It involves growing Mycobacterium tuberculosis from sputum samples on specialized media. Cultures are highly sensitive and specific but take several weeks to yield results. Cultures are also used to test for drug resistance by exposing the bacteria to various antibiotics. In many low- and middle-income countries, access to advanced diagnostic tools is limited. Traditional methods like sputum smear microscopy remain the primary diagnostic approach due to their lower cost and simpler requirements. However, these methods may miss a significant number of TB cases, particularly in individuals with Human immunodeficiency viruses co-infection or extra pulmonary TB. Drug-resistant TB poses a major challenge. Diagnosing Latent TB Infection (LTBI), where the person is infected but asymptomatic, is crucial for TB control but can be challenging. Interferon Gamma Release Assay (IGRAs) are often used, but distinguishing between LTBI and active TB can be complex and may require additional testing and clinical evaluation. Accurate diagnosis is fundamental to TB control and treatment. While traditional methods like the Tuberculin Skin Test and sputum smear microscopy remain important, advancements in diagnostic technologies are enhancing our ability to detect TB quickly and accurately. Addressing the challenges in TB diagnosis, particularly in resource-limited settings and for drugresistant strains, is crucial for reducing the burden of TB globally. Continuous study and innovation are essential to improve diagnostic tools and strategies, ultimately contributing to the global fight against tuberculosis.