This article was reviewed by the Bronchiectasis and NTM Content Review and Evaluation Committee.

Mycobacterium avium complex (MAC) is a type of nontuberculous bacteria that occurs naturally in our environment. It can be found in soil, dust, and water including naturally occurring water sources (e.g., lakes, streams, and rivers) and municipal water sources (e.g., water from a faucet or shower).¹ In most people, MAC does not cause illness. However, people with immune systems that do not work well or have lung disease, such as chronic obstructive pulmonary disease (COPD) and/or bronchiectasis are at a higher risk for developing MAC lung infections.² MAC lung infections can cause fever, cough, fatigue, weight loss and shortness of breath.

MAC lung infections are diagnosed by a combination of physical exam findings, specialized imaging (chest CT scan or lung X-ray), and laboratory tests to identify MAC in cultures of mucous spit up from the lungs.² Primary treatment for MAC typically includes antimicrobial therapy.³ A combination of different medicines are used because some MAC infections can be resistant to certain types of antibiotics.² Using multiple antibiotics reduces the chance that MAC can become resistant to the antibiotics. The decision to start antimicrobial therapy for MAC should be individualized based on a variety of clinical factors, individual patient priorities, and potential side effects.³

Researchers are currently conducting two (2) clinical trials to study a treatment and patient outcomes for newly diagnosed MAC lung disease patients:

• The ENCORE study will assess a study drug as a potential treatment option for patients newly diagnosed with a MAC lung infection.
• ARISE is a study looking to validate patient-reported outcome instrument(s) for use in newly diagnosed MAC lung disease patients. Patient-reported outcome instruments are important to accurately assess the impact of a disease and/or treatment on patients’ quality of life. ARISE is hoping to investigate which patient-reported outcomes instrument will be responsive and reliable for use among MAC patients.

In order to be considered for either one of these clinical trials participants must be at least 18 years old and recently diagnosed with MAC and have not started treatment. Participants must have a positive sputum culture for MAC within 6 months prior to screening. Those who have received treatment for their current MAC infection or have a history of more than 3 prior MAC lung infections will not be eligible.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. We recommend that you talk to your healthcare provider before choosing to participate in a clinical study. If you are interested in participating in either one of these studies, please click here to learn more.

References:

1. Centers for Disease Control and Prevention. Nontuberculous Mycobacteria (NTM) Infections | HAI | CDC. https://www.cdc.gov/hai/organisms/nontuberculous-mycobacteria.html. Accessed June 11, 2021.
2. National Institute of Health. Mycobacterium Avium Complex infections | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program (nih.gov). https://rarediseases.info.nih.gov/diseases/7123/mycobacterium-avium-complex-infections. Accessed June 14, 2021.
3. Daley CL, Iaccarino JM, Lange C, Cambau E, Wallace RJ, Andrejak C, Böttger EC, Brozek J, Griffith DE, Guglielmetti L, Huitt GA, Knight SL, Leitman P, Marras TK, Olivier KN, Santin M, Stout JE, Tortoli E, van Ingen J, Wagner D, Winthrop KL. Treatment of Nontuberculous Mycobacterial Pulmonary Disease: An Official ATS/ERS/ESCMID/IDSA Clinical Practice Guideline. Clin Infect Dis. 2020 Aug 14;71(4):905-913. doi: 10.1093/cid/ciaa1125. PMID: 32797222; PMCID: PMC7768745.