A bacterium known as Mycobacterium tuberculosis causes the bacterial infection called tuberculosis. In the past this disease was greatly feared, as there was no cure for it. But antibiotics were developed in the 1950s and it was predicted that the disease would be eradicated as the number of cases continued to drop. Then with the spread of HIV and AIDS, tuberculosis again became a problem. However, due to aggressive public health efforts in the United States, it is not a major health problem. This is not true of third world countries. In these countries TB continues to be one of the leading causes of death.
TB is very contagious and is spread when an infected person coughs. The bacteria travel from their lungs into the air and are breathed in by other people. In most people the immune system can fight off the infection. However, the people that are highly susceptible to TB are those who have HIV, those living in crowded facilities such as prisons, nursing homes, and halfway houses, health care workers, alcoholics, homeless people and anyone with a suppressed immune system. Patients with rheumatoid arthritis are also at high risk for the disease as scientists have determined there is a link between TB and some of the drugs that are prescribed for the treatment of arthritis.
The most prominent symptom of TB is a chronic cough. Other symptoms include fever, night sweats, chest pain, bloodstained phlegm, and fatigue and weight loss. There are various tests used to determine if a person has TB. A common test is a skin test in which a small amount of the protein from a killed TB bacterium is injected under the skin of your forearm. If the test is positive, a small bump will appear in the next two to three days. This test will tell if you have ever been infected with TB but it will not determine whether or not you have an active infection. TB bacteria can lie dormant in the lungs over a long period of time. If a person with a positive skin test will not be contagious if the infection is not active.
Chest x-rays will show scars on the lungs and lymph nodes of the chest. This indicates that you were infected with TB in the past. A chest x-ray can reveal signs of an active infection. The doctor may also take a sample of your phlegm. This can be examined for presence of the TB bacterium. If it is present in your phlegm, you definitely have an active infection and are contagious. If the doctor is still unsure, after performing these tests, a bronchoscopy may be performed. In this procedure, a tiny sample of your lung tissue is removed for laboratory analysis.
Most incidences of TB can be cured by antibiotics. There are several different types available and patient usually takes a combination of three or sometimes even four different types daily for six months. However, there are some TB bacteria that are resistant to these antibiotics. In this case, the infection is labelled multi-drug resistant TB.