Variable presenting features including chronic cough, weight loss, and fevers.
Increased incidence in patients with underlying lung disease, heavy smoking, and excessive alcohol consumption.
HIV-infected patients with CD4 cell count <50 cells/microlitre also at increased risk of infection.
Diagnosis of pulmonary disease in non-HIV-infected individuals requires repeated isolation of the organism from respiratory secretions, in addition to compatible symptoms and radiographical presentation.
Combination treatment with at least two drugs is essential.
Mycobacterium avium complex (MAC), also known as mycobacterium avium-intracellulare (MAI), consists of two mycobacterium species, M avium and M intracellulare. Although MAC isolates can be identified as M avium or M intracellulare by molecular techniques, there is no prognostic or treatment advantage for doing so. In humans, MAC traditionally causes three disease syndromes: pulmonary disease, cervical lymphadenitis, and disseminated disease. A fourth syndrome, a hypersensitivity pneumonitis associated with hot tub use, has also been described.
History and exam
Professor of Medicine
Mayo Clinic Center for Tuberculosis
Global HIV Education Initiative
ZT declares that he has no competing interests.
Dr Temesgen would like to gratefully acknowledge Dr Dereje S. Ayo, a previous contributor to this topic.
DSA declares that he has no competing interests.
Division of Pulmonary, Allergy, Critical Care and Sleep Medicine
Ohio State University Medical Center
JPP declares that he has no competing interests.
Infectious Diseases Unit
SV declares that he has no competing interests.
Use of this content is subject to our disclaimer