Tuberculosis (TB) is a very common serious infection caused by bacteria called Mycobacterium tuberculosis. Less often, other kinds of mycobacteria cause diseases.
What is a MAC infection?
After TB, the most common mycobacterial disease is caused by a group of bacteria called Mycobacterium avium complex (MAC).
Healthy people rarely get MAC infections
MAC infections usually happen to frail elderly people, people with a weak immune system, and people with lung damage from emphysema or TB
MAC infections usually affect your lungs, but they can also involve your lymph nodes, bones, skin, and other tissues
MAC infections are hard to treat
You'll usually have to take antibiotics for 1 or 2 years
MAC infections of the lungs
MAC infections of the lungs start slowly. Symptoms are like those of TB in the lungs and include:
Cough
Spitting up blood or mucus
Tiredness
Weight loss
Fever
Trouble breathing
Doctors test your sputum (what you cough up from deep in your lungs). If you have a MAC infection, doctors treat it with antibiotics.
MAC infections of the lymph nodes
Lymph nodes are tiny bean-shaped organs that help fight off infection. Children can get a MAC infection in their lymph nodes by eating dirt or drinking water infected with mycobacteria.
Doctors treat these infections with surgery to take out the infected lymph nodes.
MAC infection throughout the body
People with AIDS or another health problem that weakens the immune system can get a whole body MAC infection.
Symptoms include:
Fever
Anemia (a low number of red blood cells)
Diarrhea
Belly pain
If they suspect a MAC infection throughout your body, doctors will take a sample of blood or tissue to test.
Doctors treat you with 2 or 3 antibiotics at the same time.
What other types of mycobacteria infection do people get?
Other types of mycobacteria cause:
Skin infections from swimming pools or aquariums—you get red bumps on your arms and legs which usually go away without treatment, though some people may need antibiotics
Buruli ulcer—swelling of the arms, legs, or face that turns into open sores—doctors treat you with antibiotics and often surgery
Infection of wounds, tattoos, and artificial body parts (such as breast implants)—doctors treat you with antibiotics and surgery
