Smoking-Related Interstitial Lung Disease in a Non-Smoker

Abstract

SESSION TITLE: Fellow Case Report Poster - Diffuse Lung Disease I SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 25, 2016 at 01:30 PM - 02:30 PM INTRODUCTION: Pulmonary Langerhans cell histiocytosis (PLCH) is an uncommon diffuse cystic lung disease that occurs almost exclusively in young adult smokers. We present a case of PLCH in a non-smoker. CASE PRESENTATION: A 23-year-old male presented with acute onset of sharp, left-sided chest pain and shortness of breath. His past medical history was significant for two episodes of left-sided pneumothoraces, which were managed with chest tube placement. He did not have a history of current or prior cigarette smoking. He did not have a significant second-hand cigarette smoke exposure. On presentation, his vitals were stable. Physical examination revealed decreased breath sounds on the left side of the chest. Chest X-ray showed left-sided pneumothorax and bilateral diffuse interstitial infiltrates. He was treated with chest tube placement. CT of the chest revealed bilateral, multiple thick and thin walled cysts in the upper and middle lung fields with relative sparing of the bases. Video-assisted thoracoscopic lung biopsy (VATS) was obtained and mechanical pleurodesis was performed to treat his recurrent pneumothorax. Immunohistochemical staining for S-100 protein was positive in the Langerhans cells, consistent with PLCH. DISCUSSION: PLCH is a rare interstitial lung disease characterized by infiltration and proliferation of Langerhans cells. It occurs mostly in young adults, 20-40 years of age. Cigarette smoking is considered to be the inciting factor. There are no direct experimental data that support the role of cigarette smoke in the pathogenesis of PLCH. But, there are several observational studies, suggesting that the disease may be causally related to smoking. A history of current or previous cigarette smoking is identified in up to 97 percent of patients. PLCH has also been described in association with malignancy especially bronchogenic carcinoma and Hodgkin’s lymphoma. It is extremely rare in non-smokers and the etiology remains unknown. CONCLUSIONS: The overwhelming majority of adult patients with PLCH smoke cigarettes or were exposed to substantial second-hand smoke. PLCH has been described under the spectrum of smoking-related interstitial lung diseases. PLCH in non-smokers is not well studied. Reference #1: Suri H, Yi E, Nowakowski G, et al. Pulmonary langerhans cell histiocytosis. Orphanet J Rare Dis. 2012; 7: 16. doi: 10.1186/1750-1172-7-16 PMCID: PMC3342091 Reference #2: Abbott G, et al. Pulmonary Langerhans cell Histiocytosis1. Archives of the AFIP. DOI: http://dx.doi.org/10.1148/rg.243045005 DISCLOSURE: The following authors have nothing to disclose: Sathish Kumar Krishnan, Kumar Shah, Gurminder Dhillon No Product/Research Disclosure Information