Description
Mycobacterium avium complex (MAC) is a group of mycobacteria comprising Mycobacterium intracellulare and Mycobacterium avium, that are commonly grouped together because they infect humans together.
M. avium, M. intracellulare, and M. chimaera are each saprotrophic organisms present in soil and water; entry into hosts is usually via the gastrointestinal tract, but also can be via the lungs.
MAC infection can cause chronic pulmonary disease and lymphadenitis, and can cause disseminated disease, especially in people with immunodeficiency.
MAC infections can cause fevers, diarrhea, malabsorption, as well as loss of appetite and weight loss, and can disseminate to the bone marrow.