Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Tuberculous Bronchiolitis
- Radiologic Findings
- Chest radiograph at presentation shows diffuse multiple nodules in the whole lung. CT scans demonstrate multiple scattered nodules with tree-in-bud pattern. Some bronchi/bronchioles appear dilated and thickened. Also note mosaic attenuation of the lung. At this time, sputum examination did not reveal any infectious organism. Chest radiograph obtained 3 months later shows aggravation of the lung lesions, when acid-fast bacilli were identified from sputum exam.
- Brief Review
- On HRCT, pulmonary tuberculosis may show centrilobular distributed, small rounded areas of high attenuation, branched linear areas of high attenuation contiguous to the small rounded areas, dilated airways with thick walls, and decreased lung attenuation in the peripheral areas, mimicking DPB. In cases with such tuberculous bronchiolitis, centrilobular nodules and linear branching shadows are caused by peribronchiolar granulomatous inflammation.
There are two main theories concerning the development of tuberculous endobronchial lesion. One holds that the bronchial changes originate from the contact of the mucosa with the infected sputum from the lesions in the distal lung parenchyma, particularly those with cavities (1). This theory cannot explain the mechanism in patients who have few acid-fast bacilli in the sputum or have noncavitary parenchymal lesions as in our cases. The other more recent theory suggests a submucosal spread of tubercle bacilli through lymphatics to the peribronchial region from the lung parenchyma (2-4). A detailed postmortem study of endobronchitis by Myerson (3) showed evidence for retrograde passage of tubercle bacilli via lymphatics from the bronchioles and subsegmental bronchi to the main stem bronchus. Another possibility is the direct extension of the tuberculous process from an adjacent parenchymal lesion or tuberculous lymphadenitis (4).
- References
- 1. Salkin D, Cadden AV, Edson RC. The natural history of tuberculous tracheobronchitis. Am Rev Tuberc 1943;47:351-359
2. Albert RK, Petty TL. Endobronchial tuberculosis progressing to bronchial stenosis. Chest 1976; 70:537-539
3. Myerson MC. Tuberculosis of the trachea and bronchus. Springfield, Illinois: Charles C Thomas, 1944:250-275
4. Smith LC, Schillaci RF, Sarlin RF. Endobronchial tuberculosis. Serial fiberoptic bronchoscopy and natural history. Chest 1987;91:644-647
- Keywords
- Lung, Airway, Infection,