Diseases & Conditions
Tuberculosis (TB) is infection with Mycobacterium tuberculosis, a type of bacterium. Tuberculosis infection typically occurs after repeated or prolonged exposure to the coughing of an actively infected person. Persons with HIV infection are at particularly high risk. Infection can involve any organ in the body, but the lungs are the most common site of damage. In active infection, there is damage to organs. In latent infection, the person carries the bacteria but does not have current signs of active infection. Latent TB infection is important to diagnose and treat because it can become active infection. Multidrug-resistant TB is resistant to (cannot be killed by) standard antibiotics. This type of TB arises from improper or incomplete treatment of TB infection or through exposure to a person infected with this type of bacterium.
Symptoms vary depending on the patient's age and which organs are infected.
Fever and sweating (particularly at night)
Unexplained weight loss
Loss of appetite
Persistent cough that may be associated with bloody sputum
Difficulty breathing or chest pain with breathing
In addition to a complete medical history and physical examination, your doctor will perform a test for TB by injecting under the skin of your forearm a small amount of protein derived from TB bacteria. This TB skin test must be examined 48 to 72 hours later by a doctor or nurse who will measure any reaction at the injection site. If you have an active cough, your doctor will obtain a sample of your sputum to examine for the bacteria. Your doctor may also order a chest x-ray (a picture of the lungs) to look for signs of the infection or blood tests to determine whether other organs are infected.
Appropriate treatment usually requires a regimen of 3 to 4 antibiotics taken daily for a minimum of 6 to 9 months. Treatment of multidrug-resistant TB requires additional medications and may last several years. Medications are given under close supervision to ensure that all doses are taken and to monitor for any adverse effects.
FOR MORE INFORMATION
American Lung Association
National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
Division of Tuberculosis Elimination
Source: JAMA. 2008;300(4):464.