Title |
Lessons from Mycobacterium avium complex-associated pneumonitis: a case report
|
---|---|
Published in |
Journal of Medical Case Reports, May 2008
|
DOI | 10.1186/1752-1947-2-152 |
Pubmed ID | |
Authors |
Victor Zota, Sheryn M Angelis, Armando E Fraire, Ciaran McNamee, Shasta Kielbasa, Daniel H Libraty |
Abstract |
Mycobacterium avium complex (MAC) is an increasingly recognized cause of pulmonary disease in immunocompetent individuals. An acute form of MAC lung disease, MAC-associated pneumonitis, has generally been associated with the use of hot tubs. There is controversy in the literature about whether MAC-associated pneumonitis is a classic hypersensitivity pneumonitis or is a direct manifestation of mycobacterial infection. We report the second case in the literature of MAC-associated pneumonitis not related to the use of hot tubs. The source of MAC in a 52-year-old immunocompetent patient was an intrapulmonary cyst containing numerous acid-fast bacilli. The patient developed disseminated miliary nodules throughout both lung fields. Histological examination of resected lung tissue revealed well-formed, acid-fast negative granulomas composed predominantly of CD4+ T-cells and CD68+ histiocytes. The granulomas were strongly positive for tumor necrosis factor-alpha, a pro-inflammatory cytokine. The attempt to classify MAC-associated pneumonitis as either a classic hypersensitivity pneumonitis or a direct manifestation of mycobacterial infection is not particularly useful. Our case demonstrates that MAC-associated pneumonitis is characterized by a vigorous T-helper 1-like, pro-inflammatory, immune response to pulmonary mycobacterial infection. The immunopathology provides a rationale for clinical studies of anti-MAC therapy with the addition of anti-inflammatory agents (for example, corticosteroids) to hasten the resolution of infection and symptoms. |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Unknown | 17 | 100% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Student > Bachelor | 7 | 41% |
Student > Master | 4 | 24% |
Student > Doctoral Student | 1 | 6% |
Researcher | 1 | 6% |
Unknown | 4 | 24% |
Readers by discipline | Count | As % |
---|---|---|
Medicine and Dentistry | 9 | 53% |
Computer Science | 1 | 6% |
Veterinary Science and Veterinary Medicine | 1 | 6% |
Immunology and Microbiology | 1 | 6% |
Neuroscience | 1 | 6% |
Other | 0 | 0% |
Unknown | 4 | 24% |