Related Experiment Video
Updated: Feb 15, 2026

Intradermal Inoculation of Mycobacterium avium in the Mouse Ear
Published on: July 3, 2025
Pathological findings of bronchiectases caused by Mycobacterium avium intracellulare complex
Jiro Fujita1, Yuji Ohtsuki, Eriko Shigeto
1First Department of Internal Medicine, Kagawa Medical University, 1750-1 Miki-cho Kita-gun, Kagawa 761 0793, Japan. jiro@kms.ac.jp
Abstract:
It has been argued whether bronchiectasis is truly caused by MAC infection or just a predisposed condition in which MAC colonizes. Our present study was designed to evaluate the pathological findings of bronchiectases caused by Mycobacterium avium intracellulare complex (MAC) lung infection and to demonstrate MAC in the lesion of bronchiectases. A retrospective study was performed in nine cases with positive cultures for MAC in whom lung resections were performed. A determination of whether or not MAC caused pulmonary disease was made using the 1997 criteria required by the American Thoracic Society. In addition, MAC were cultured from all nine lung specimens. Pathological findings of bronchiectases were evaluated in these nine patients. Destruction of bronchial cartilage and smooth muscles layer, obstruction of airway by granulomas, and ulceration of bronchial mucosa were frequently observed. Our present study demonstrates that destruction of fundamental bronchial structure due to extensive granuloma formation throughout the airways was likely the main cause of bronchiectases in MAC infection.
Related Concept Videos
Intracellular Signaling Cascades
Finding the Center of Gravity
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Cardiovascular System Abnormal Findings I: Inspection and Palpation
Abnormal findings observed during an inspection
Respiratory System Abnormal Finding I: Inspection and Percussion
Inspection Findings
During an inspection, several findings may suggest the presence of respiratory distress or disease. Pursed-lip breathing, where exhalation is slowed by...
Finding Electric Potential From Electric Field

