Mycobacterium avium intracellulare (MAI) infections, also known as nontuberculous mycobacterial (NTM) infections, are a type of chronic bacterial infection caused by the Mycobacterium avium complex (MAC). This complex consists of two closely related species: Mycobacterium avium and Mycobacterium intracellulare. These bacteria are found in the environment, including water, soil, and biofilms.
MAI infections most commonly affect individuals with a compromised immune system, such as those with HIV/AIDS, certain cancers, organ transplant recipients, or individuals on immunosuppressive therapy. However, they can also occur in individuals with a normally functioning immune system, particularly those with existing lung diseases such as bronchiectasis or chronic obstructive pulmonary disease (COPD).
Infections caused by MAI typically target the lungs, but they can also affect other parts of the body, such as the lymph nodes, skin, joints, and intestines. Symptoms may include persistent cough, shortness of breath, fatigue, weight loss, night sweats, fever, abdominal pain, and diarrhea.
Diagnosis of MAI infections involves a combination of clinical evaluation, identification of typical radiographic patterns, and laboratory tests, such as sputum culture or biopsy. Treatment of MAI infections usually requires a combination of antibiotics for an extended duration, often lasting months to years, due to the slow-growing and intracellular nature of the bacteria.
Prevention and management of MAI infections involve reducing exposure to MAC organisms by avoiding environmental sources, maintaining good hygiene practices, and appropriately managing underlying conditions that can increase susceptibility to infections.
