This information is provided by the National Institutes of Health (NIH)
Genetic and Rare Diseases Information Center (GARD).
Mycobacterium avium complex (MAC) refers to infections caused by two types of bacteria: Mycobacterium avium and Mycobacterium intracellulare. MAC bacteria do not make most people sick. However, people with immune systems that do not work well (from HIV/AIDS or certain cancers for example) or people with lung disease (such as chronic obstructive pulmonary disease (COPD) or cystic fibrosis) are at the greatest risk for getting sick from MAC Infections. Elderly women are also at higher risk to get sick from MAC infections.
There are 3 types of MAC infections.
- Pulmonary MAC infections – Affect the lungs and are the most common type. These mainly affect elderly women and people who already have lung disease.
- Disseminated MAC infections – Have spread throughout the body. This type is usually seen in people with advanced AIDS.
- MAC-associated lymphadenitis – Causes swelling of the lymph nodes (especially in the neck) and is the most common in young children who have normal immune systems.
While the symptoms are different for each type of infection, general symptoms include fever, night sweats, weight loss, and fatigue. MAC bacteria are found in water, soil, and dust. They infect people when the bacteria are inhaled or swallowed. MAC bacteria are not usually spread from person to person. MAC infections are diagnosed by a combination of imaging scans and identifying the bacteria in cultures of cells from the infected area. Treatment for MAC infection depends on the type and may include antibiotics, antiviral medications, or surgery.
For more information, visit GARD.