What Is TB Disease?
TB bacteria become active if the immune system can't stop them from growing. The active bacteria begin to multiply in the body and cause TB disease.
Some people develop TB disease soon after becoming infected, before their immune system can fight the TB bacteria. O
ther people may get sick later, when their immune system becomes weak for some reason. Babies and young children often have weak immune systems.
People infected with HIV, the virus that causes AIDS, have very weak immune systems.
Other people can have weak immune systems, too, especially people with any of these conditions:
* substance abuse
* diabetes mellitus
* cancer of the head or neck
* leukemia or Hodgkin's disease
* severe kidney disease
* low body weight
* certain medical treatments (such as corticosteroid treatment or organ transplants)
Symptoms of TB depend on where in the body the TB bacteria are growing. TB bacteria usually grow in the lungs. TB in the lungs may cause a bad cough that lasts longer than 2 weeks, pain in the chest, and coughing up blood or sputum (phlegm from deep inside the lungs).
Other symptoms of TB disease are:
* weakness or fatigue
* weight loss
* no appetite
* sweating at night
For information on how TB disease is treated, see the section on TB disease.
Taken from here.