A31.0

Clinical Causes: Infection by Mycobacterium avium complex (MAC), which includes Mycobacterium avium and Mycobacterium intracellulare. Infection due to Mycobacterium kansasii. Exposure to contaminated environments, such as soil or water sources where these bacteria are present. Pre-existing lung conditions, like chronic obstructive pulmonary disease (COPD), bronchiectasis, or previous lung damage, which can make the lungs more susceptible to infection. Weakened immune system, including conditions such as HIV/AIDS, use of immunosuppressive medications, or chemotherapy. Inhalation of aerosolized bacteria from environmental sources.

Key Symptoms: Chronic cough, often persistent and sometimes producing mucus or sputum. Shortness of breath or wheezing. Chest pain or discomfort. Fatigue and malaise. Unintentional weight loss. Occasional fever and night sweats. General feeling of being unwell. Hemoptysis, or coughing up blood, in advanced cases.

Diagnosis Path: Chest X-rays or computed tomography (CT) scans to identify lung abnormalities such as nodules, cavities, or infiltrates. Sputum samples or bronchoalveolar lavage to test for the presence of Mycobacterium species. Nucleic acid amplification tests (NAAT) for rapid detection of bacterial DNA. Culture tests that allow identification of specific bacterial strains. Assessment of immune status, particularly in immunocompromised individuals.

Treatment Protocols: Prolonged courses of specific antibiotics such as macrolides (e.g., azithromycin or clarithromycin). Addition of ethambutol or rifamycins depending on bacterial sensitivity. Monitoring for drug side effects, as therapy often extends over months to years. In some cases, corticosteroids are used if inflammation is severe. Surgical intervention may be considered in rare circumstances, such as removing localized lung damage.