Smoking related interstitial lung disease Inhalation of tobacco smoke is a risk factor for developing respiratory diseases as chronic obstructive pulmonary disease, lung cancer and many cardiovascular diseases. Recently, a new group of interstitial lung diseases (ILD) related to cigarette smoking (SR-ILD) have been described. This group includes pulmonary Langerhans cell histiocytosis, respiratory bronchiolitis, smoking-associated interstitial fibrosis, desquamative interstitial pneumonia. The diagnosis is usually difficult, and the use of some clinical clues, high-resolution computerized tomography, and histopathologic findings in lung biopsy could help to differentiate between the various entities. We present a report of clinical cases of patients with SR-ILD seen in our center, and a review of the literature of the above entities.