Tuberculosis (TB) is an infectious disease caused by bacteria in the Mycobacterium genus, especially Mycobacterium tuberculosis. TB usually affects your lungs, but it can attack any part of your body.
TB affects only the lungs in 75 percent of cases. Specific symptoms of pulmonary TB include a productive cough that persists longer than three weeks, bloody sputum and chest pain.
Pulmonary TB also causes general, systemic symptoms such as chronic fatigue, fever and chills. It also frequently causes a loss of appetite, weight loss and a pale complexion.
TB moves out of the lungs in 25 percent of cases and may affect virtually any part of your body. For example, TB of the nervous system can cause meningitis.
Additional Infection Sites
Extrapulmonary TB can cause other symptoms based on the specific area affected. TB of the lymphatic system can cause scrofula, TB of the pleura causes tuberculosis pleurisy, and TB in the bones is known as Pott's disease.
Disseminated TB occurs when it becomes widely distributed throughout your body. This form of TB generally has nonspecific symptoms, with the most common specific symptoms being an enlarged liver and an enlarged spleen.