Diagnosis and Treatment

The American Thoracic Society recommends that cessation of smoking is the most effective treatment for patients with smoking-related interstitial lung disease, with resolution of symptoms in up to 90% of cases and improvement of cough in 94-100% of patients within the first year 1
The American College of Chest Physicians suggests that Bronchiolitis-Interstitial Lung Disease (RB-ILD) is the most likely diagnosis in smokers with basal interstitial reticulation, characterized by ground-glass opacities and centrilobular nodules on HRCT 2, 3, 4
The American Journal of Respiratory and Critical Care Medicine states that Desquamative Interstitial Pneumonia (DIP) represents a histological spectrum with RB-ILD, with more extensive accumulation of macrophages 2, 5
The American Thoracic Society reports that the 10-year survival rate for DIP is approximately 70%, with resistance to treatment in a significant minority 2, 5
The American College of Chest Physicians recommends that Non-Specific Interstitial Pneumonia (NSIP) can present with bilateral reticular opacities in the lower zones, but subpleural sparing can help distinguish it 4

Treatment Approach

The American College of Chest Physicians suggests that combination therapy with nicotine replacement (patch + short-acting form) or varenicline, along with behavioral counseling, represents the first-line treatment 6
The American Thoracic Society recommends that at least 4 sessions of behavioral therapy during each 12-week course of pharmacotherapy are recommended 6
The American College of Chest Physicians states that avoiding occupational risks and environmental pollutants, including eliminating exposure to secondhand smoke, is crucial 1

The American Journal of Respiratory and Critical Care Medicine reports that the disease course is heterogeneous, with a significant minority presenting progression despite smoking cessation 2, 3
The American Thoracic Society suggests that most patients with RB-ILD have a substantially better prognosis than those with idiopathic pulmonary fibrosis 7, 1
The American College of Chest Physicians states that for DIP, the 10-year survival rate is approximately 70% 7, 2, 5

The American College of Chest Physicians recommends that follow-up imaging is recommended to monitor progression 8
The American Thoracic Society suggests that close follow-up with repeated CT scans at 3-6 months if the initial evaluation is non-diagnostic 8

In smokers presenting with characteristic HRCT findings (ground‑glass opacities and centrilobular nodules) and bronchoalveolar lavage that shows smoker’s macrophages without lymphocytosis, respiratory bronchiolitis‑associated interstitial lung disease (RB‑ILD) can often be diagnosed without surgical lung biopsy.  9, 10, 11

RB‑ILD generally carries a substantially better prognosis than idiopathic pulmonary fibrosis, yet a notable minority of patients experience disease progression despite successful smoking cessation. 10, 11
Desquamative interstitial pneumonia (DIP) has an approximate 10‑year survival rate of 70%; however, a significant subset of patients exhibits resistance to standard therapy. 11

Bronchoalveolar lavage showing lymphocytosis favors hypersensitivity pneumonitis, while HRCT demonstrating subpleural sparing is more typical of nonspecific interstitial pneumonia (NSIP); these features help distinguish these entities from smoking‑related ILDs. 9

Clinicians should not assume that smoking cessation alone will resolve RB‑ILD or DIP, because a proportion of patients progress despite abstinence. 9, 10, 11