Introduction: Smoking can cause a variety of pulmonary interstitial diseases. Pulmonary fibrosis has traditionally been considered a non-smoking-related disease. Recently, however, evidence of smoking-induced fibrosis has emerged.
Subjects and methods: A group of eight patients from the pulmonary clinic in Rabin Medical Center with a combine presentation of fibrosis and emphysema was identified retrospectively. All patients underwent chest computed tomography and pulmonary function tests. One patient underwent lung-heart transplantation and a complete review of his lung pathology was obtained. Transbronchial biopsy was performed in 3 additional patients and echocardiography was performed to evaluate the pulmonary vasculature.
Results: Upper-lobe emphysema with bulluos changes was found in all patients. In addition, a basal interstitial process was recognized, ranging from ground glass opacities to severe pulmonary fibrosis, with honeycombing. The radiological findings matched the pathological results of combined emphysema and usual interstitial pneumonia. Pulmonary function tests were also in accord, showing severe hypoxemia with mild obstruction, normal-to-mildly reduced lung volumes and a severe decrease in diffusion capacity. Most of the patients had moderate-to-severe pulmonary hypertension as well as diffuse coronary artery disease.
Conclusion: Our findings are in line with emerging evidence that the spectrum of interstitial damage caused by smoke includes not only Langerhans cell hystiocytosis, respiratory bronchiolitis or desquamative interstitial pneumonia but also advanced usual interstitial pneumonitis as well. We believe that in some patients smoking plays a destructive role by a variety of mechanisms and can cause emphysema, lung fibrosis as well as pulmonary vasculopathy and hypertension. Future studies are needed to define the genetics and pathophysiology of this uncommonly reported clinical syndrome.