Bronchiolitis Obliterans Diagnosis and Management

Radiographic Findings

Chest X-ray findings in bronchiolitis obliterans may include bilateral interstitial patterns, ground-glass opacities, and occasionally irregular linear or nodular interstitial infiltrates, as reported by the American Thoracic Society 2, 3
X-ray may appear normal in early disease stages, making it an insensitive tool for early diagnosis, according to the World Journal of Emergency Surgery 4
CT scan is more sensitive than X-ray and typically shows patchy airspace consolidation, ground-glass opacities, small nodular opacities, bronchial wall thickening and dilation, and mosaic attenuation pattern on expiratory imaging, as described by the European Respiratory Society 1, 3, 5

Military deployment to Iraq/Afghanistan has also been associated with constrictive bronchiolitis, as noted by the American College of Radiology 1

Patients typically present with progressive shortness of breath, dry cough, decreased exercise tolerance, and inspiratory crackles on chest examination, as reported by the American College of Radiology and the American Thoracic Society 1, 2, 3
Pulmonary function tests usually show restrictive pattern defects and resting and exercise arterial hypoxemia is common, according to the American Thoracic Society 2

Bronchiolitis obliterans must be differentiated from other obstructive lung diseases including COPD, asthma, bronchiectasis, and tuberculosis, as recommended by the European Respiratory Society 1, 5
Tissue biopsy may be necessary when imaging is negative but clinical suspicion remains high, as suggested by the American College of Radiology 1
High-resolution CT (HRCT) is the preferred imaging modality when bronchiolitis obliterans is suspected, and expiratory CT imaging is particularly important to identify air trapping, which is characteristic of small airway disease, as described by the American College of Radiology 1

Mortality from acute interstitial pneumonitis, which may have similar radiographic findings, can exceed 60%, as reported by the American Thoracic Society 2