Sarcoidosis with pulmonary fibrosis: CT patterns and correlation with pulmonary function

Area of Science:

• Pulmonary Medicine
• Radiology
• Immunology

Background:

• Sarcoidosis is an inflammatory disease that can cause pulmonary fibrosis.
• Identifying patterns of fibrosis is crucial for understanding disease progression and patient outcomes.

Purpose of the Study:

• To identify computed tomography (CT) patterns of pulmonary fibrosis in patients with sarcoidosis.
• To correlate these CT patterns with pulmonary function test (PFT) results.

Main Methods:

• Retrospective review of CT scans from 80 patients with proven sarcoidosis and fibrotic changes on chest radiographs.
• Classification of CT findings into three main patterns: bronchial distortion, honeycombing, and linear.
• Correlation of CT patterns with PFTs, including lung volumes, diffusing capacity, and airflow rates.

Main Results:

• Three predominant CT patterns were identified: bronchial distortion (47%), honeycombing (29%), and linear (24%).
• The honeycomb pattern was associated with restrictive lung disease and reduced diffusing capacity for carbon monoxide.
• Bronchial distortion correlated with decreased expiratory airflow, while the linear pattern showed the least functional impairment.

Conclusions:

• CT is valuable for categorizing patients with fibrotic pulmonary sarcoidosis into distinct subgroups.
• The identified CT patterns may represent different distributions of fibrotic lesions and associated functional impairments.
• Nodular lesions, suggestive of active disease, were frequently observed with linear and distorted patterns.