Desquamative interstitial pneumonia in a child related to cigarette smoke

An 8-year-old white male was referred to our clinic for a 1-year history of decreased appetite and no weight gain. His entire workup failed to demonstrate cystic fibrosis, or any infectious or immune-related diseases. Chest imaging and clinical picture suggested parenchymal lung disease. Histopathology examination of the video-assisted thoracoscopic biopsy of his lungs showed a desquamative interstitial pneumonia (DIP)-like pattern that resembled that of adult smokers with the same disease. Genes for surfactant proteins B and C and the transporter ABCA3 were all negative. Furthermore, lack of any genetic disorder for surfactant proteins, along with his history of heavy exposure to 10 pack-years of indoor secondhand smoke suggests that this child's DIP is due to secondhand cigarette exposure. He had nearly complete resolution of his symptoms after a year of treatments with pulse steroid and hydroxycholoroquine. To the best of our knowledge this is the first case of cigarette smoke-related DIP reported in a child.