Tuberculosis is caused by the Mycobacterium tuberculosis bacterium, which can infect the lungs and other parts of the body. Common symptoms include cough, sputum, fever, fatigue, weight loss and night sweats. Diagnosis involves tests like the tuberculin skin test, blood tests, chest X-rays and sputum examinations. Treatment consists of a combination of antibiotics over a period of 6-9 months to fully cure the infection.