Interstitial Lung Disease, Respiratory Bronchiolitis-Associated

Key Features

• Presentation similar to usual interstitial pneumonitis (UIP) but occurs in younger patients

• Patients are invariably heavy smokers

• Usually occurs without symptoms or physiologic evidence of lung disease

• Prognosis is better than in UIP; median survival > 10 years

Clinical Findings

• Age 40–45 years

• Insidious dry cough with exertional dyspnea over months to years

• Diffuse parenchymal infiltrates

Diagnosis

• High-resolution CT shows nodular or reticulonodular pattern, more likely to reveal diffuse ground-glass opacities

• Honeycombing is rare

• May also show upper lobe emphysema

Treatment

• Spontaneous remission occurs in up to 20% of patients

• Smoking cessation is crucial

• Corticosteroids thought to be effective, but there are no randomized clinical trials to support this view