Tuberculosis, commonly known by its short form TB is an infectious disease that is caused by the bacterium Mycobacterium tuberculosis or MTB. TB affects the lungs generally but it can also affect other body parts. Most TB infections do not show any symptoms and this is called latent tuberculosis. Only about 10% of latent infections progress to active disease. But, if left untreated it can be fatal in 50% of the cases. The classis TB symptoms are chronic cough with sputum that contains blood, night sweats, fever and weight loss. It is because of the weight loss that TB was historically known as ‘consumption’. If other organs are affected, a wide range of symptoms are also seen.