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Updated: May 10, 2026

Intradermal Inoculation of Mycobacterium avium in the Mouse Ear
Published on: July 3, 2025
Mucoid impaction of the bronchi caused by Mycobacterium avium
Yoshihiro Kobashi1, Keiji Mouri, Yasushi Obase
1Department of Respiratory Medicine, Kawasaki Medical School, Japan. yoshihiro@med.kawasaki-m.ac.jp
Abstract:
A 25-year-old woman with a past history of congenital adrenal cortex hypertrophy visited our hospital complaining of a continuous cough. On chest CT, a localized bronchiectatic lesion was recognized with mucoid impaction in the right lower lobe. Because we obtained a positive smear test for acid-fast bacilli and polymerase chain reaction (PCR) of the bronchoscopic specimens was positive for M. avium, we administered combined chemotherapy; however, the clinical effect was poor and video-assisted thoracoscopic surgery (VATS) was performed. As the histological findings revealed a granuloma with caseating necrosis and mucous plugs containing M. avium in the respiratory bronchioles, we diagnosed the patient with mucoid impaction of the bronchi (MIB) due to M. avium.
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