Extrapulmonary TB can affect organs other than the lungs

The most common type of tuberculosis is the one that affects the lung popularly referred to as Pulmonary Tuberculosis. Pulmonary tuberculosis is caused predominantly by Mycobacterium tuberculosis when droplet nuclei with bacilli are inhaled.

However, TB bacilli can involve any organ system in the human body. TB most commonly affects the lungs — what’s known as the body’s pulmonary system. But it affects other organs too, what’s known as extrapulmonary TB.

All those who get infected do not necessarily develop TB disease. The lifetime risk of breaking down to disease among those infected with TB is 10-15 per cent. TB is the leading cause of death in the world from a bacterial infectious disease.

Among extrapulmonary TB, Lymphadenopathy TB (involvement of lymph nodes) is the most common manifestation. The Lymph nodes are oval-shaped structures and are part of the human adaptive immune system. The Lymph node involvement is generally noted in the nodes around the neck.

However, in the last few decades with the advancement in the field of medical science and accessibility to CAT (CT of the Thorax) scans, more and more isolated mediastinal lymphadenopathy is being recognised. Mediastinum is the middle portion of the chest which holds your heart and the lungs. In the old, surgical procedures like mediastinoscopy were used to sample these nodes. Just like any other diagnostic tool such as Endoscopy, Colonoscopy, or Coronary Angiogram, EBUS-TBNA is a semi-invasive procedure performed by Interventional Pulmonologists by manoeuvring the flexible EBUS Scope through the mouth/ nasal cavity into the trachea (windpipe) to visualize the lesion using low frequency (5-15Hz) real-time ultrasound probe with great accuracy.

It further enables us to perform an FNA or biopsy without obvious pain or any other major complications that we may usually encounter in mediastinoscopy or other invasive thoracic procedures. It is extremely safe 99.3 per cent with minimal complications such as minor bleeding, cough, fever, and in rare cases mediastinitis.