Abstract
Childhood interstitial lung diseases are a heterogeneous group of rare chronic respiratory disorders characterized by variable types and degree of interstitial and alveolar inflammation. The etiology is various, some of these diseases are very rare and sometimes etiology can not be found.We presented four patients with unusual presentation of ILD.First one is a 18 month-old girl with surfactant protein C deficiency, presented unexpected, life-threatening pneumatoceles in the course of the disease. Second one is 11 year-old boy with respiratory bronchiolitis associated interstitial lung disease due to heavy passive smoking exposure and he is the first child case in the literature. Third one is 4 month-old boy and had neuroendocrine cell hyperplasia with clinical, radiological and pathological diagnosis. Although his brother had the same clinical and radiological findings, he was died at the age of 18 months as death was not reported due to NEHI before. Forth one is 8 year-old girl with systemic lupus erythematosus. She had only interstitial lung involvement without arthritis, rash, hematuria, hematological abnormalities, proteinuria, eye or any other organ involvement of SLE.The diagnosis of ILD is often difficult and reqiures detailed history and physical examination, diagnostic imaging, pulmonary function testing, wide laboratory testing and even invasive procedures such as bronchoscopy and in most cases open lung biopsy. Diagnose of ILD requires to suspect and elaborate in children and could be more difficult in unusual presentations.