Peribronchial Thickening on Chest X-ray: Clinical Significance

Pathophysiologic Basis

Peribronchial thickening reflects abnormalities in the peribronchovascular interstitium, which can manifest through collagen deposition and fibrosis of peribronchiolar alveolar septa, often accompanied by peribronchiolar metaplasia, as noted by the European Respiratory Review 2, 3

Acute bronchitis or early asthma exacerbation is the most common cause when peribronchial thickening appears with cough but without consolidation, pleural effusion, or cardiomegaly, according to Praxis Medical Insights 1, 4
Bronchiolocentric fibrosis, characterized by thickening of peribronchiolar alveolar septa, is particularly seen in hypersensitivity pneumonitis with a bronchiolocentric distribution pattern, as reported by the European Respiratory Review and Chest 2, 3, 5
Bronchiectasis, though chest radiography has poor sensitivity (69-71%) and may miss up to 34% of cases detected on CT, as noted by Praxis Medical Insights 1, 6

Chest radiography is relatively insensitive for airway abnormalities, with sensitivity for detecting bronchiectasis being only 66-69%, and up to 34% of radiographs appearing normal despite CT-confirmed disease, according to Praxis Medical Insights 1, 6
In patients with chronic cough and normal chest radiographs, CT identified bronchiectasis in 27% and bronchial wall thickening in 21%, as reported by Praxis Medical Insights 1

The American College of Chest Physicians and American College of Radiology guidelines recommend not routinely ordering chest CT as initial evaluation for acute cough with peribronchial thickening, as noted by Praxis Medical Insights 1, 4
Empiric treatment with first-generation antihistamine-decongestant combination should be initiated for suspected upper airway cough syndrome, expecting improvement within days to 1-2 weeks, according to Praxis Medical Insights 1
Spirometry with bronchodilator response should be performed if symptoms persist beyond 2-3 weeks to assess for underlying asthma, as recommended by Praxis Medical Insights 4
High-resolution CT with 1.5mm thin slices should be reserved for symptoms persisting beyond 8 weeks despite appropriate therapy, recurrent episodes, or concerning features, as noted by Praxis Medical Insights 1, 4