Treatment of Mycobacterium avium complex pulmonary disease

Abstract

Background: Nontuberculous mycobacteria are mycobacteria other than those that cause tuberculosis and leprosy and can cause infections in various parts of the body, predominantly the lungs. Of approximately 200 species of nontuberculous mycobacteria, only about 10 are linked to pulmonary infections, with <i>Mycobacterium avium</i> complex (MAC) being the most common.Current Concepts: The standard treatment for pulmonary diseases caused by the MAC is combination therapy, including macrolide antibiotics and other antibiotics such as ethambutol and rifampin. Among macrolide antibiotics, azithromycin and clarithromycin are commonly used for managing MAC pulmonary diseases, and in cases with extensive lesions, amikacin injections are administered concurrently during the initial stages of treatment. Ensuring an overall treatment duration of an additional 12 months after negative culture conversion is recommended in affected patients. However, despite an extended treatment period, the cure rate remains at 60~70%. Recently, an inhalable liposomal form of amikacin, marketed as ARIKAYCE, has been developed. It has been approved by the US Food and Drug Administration as an effective treatment for refractory MAC pulmonary diseases. When ARIKAYCE was used for an additional 6 months or more in patients with refractory MAC pulmonary diseases, approximately 29% of patients achieved additional treatment success. However, it has yet to be officially imported into South Korea, and a high monthly cost restricts its practical use in the country. Therefore, the treatment of MAC pulmonary disease in South Korea will remain a challenge, unless a more effective treatment emerges.Discussion and Conclusion: MAC pulmonary disease requires long-term combination antibiotic therapy, usually with macrolides, ethambutol, and rifampin, and amikacin injections are recommended for cases with extensive lesions. The lack of effective drugs hampers treatment, increasing the burden of antibiotic side effects. Therefore, more research is urgently needed for better treatment of MAC pulmonary disease.