Four cases of pulmonary Mycobacterium avium intracellulare complex presenting as a solitary pulmonary nodule and a review of other cases in Japan.
OBJECTIVE
To evaluate clinical findings of patients with a solitary pulmonary nodule in Japan caused by pulmonary Mycobacterium avium complex (MAC) disease.


METHODS
The authors investigated the clinical features of 12 patients diagnosed as having pulmonary MAC disease who had presented with a solitary pulmonary nodule.


RESULTS
The causative microorganisms were M. avium in seven patients, Mycobacterium intracellulare in two and MAC in three. The diagnostic methods were bronchoscopic biopsy or percutaneous lung biopsy in three patients and surgical operations in the remaining nine. Eleven patients had a complete surgical resection of the nodule and antituberculous drugs were administered to eight. On X-ray, there was an absence of calcification, satellite lesions, cavities, or bronchoectasis that are often thought to be characteristic of pulmonary mycobacterial disease. Differentiation from lung cancer was thought necessary in five patients. There was no microbiological or radiological relapse in those who underwent complete surgical resection.


CONCLUSIONS
Because treatment is often poorly effective for patients with pulmonary non-tuberculous mycobacterial disease, it is important to identify the causative microorganisms by performing a culture examination of resected lung tissue especially if there is a solitary pulmonary nodule.
Kobashi
Yoshihiro
Y
Department of Medicine, Division of Respiratory Diseases, Kawasaki Medical School, Kawasaki, Japan. yoshihiro@med.kawasaki-m.ac.jp
Fukuda
Minoru
M
Yoshida
Kouichiro
K
Miyashita
Naoyuki
N
Niki
Yoshihito
Y
Oka
Mikio
M
D000328:Adult; D000368:Aged; D001706:Biopsy; D001999:Bronchoscopy; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015269:Mycobacterium avium Complex / Q000302:isolation & purification*; D015270:Mycobacterium avium-intracellulare Infection / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D011379:Prognosis; D012189:Retrospective Studies; D003074:Solitary Pulmonary Nodule / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery; D020775:Thoracic Surgery, Video-Assisted