Abstract
The case of a boy aged 4 yrs and 7 months, with isolated pulmonary involvement by Langerhans' cell histiocytosis is reported. The presentation of the disease was a sudden pneumothorax, with no previous signs of respiratory disease. The case was confirmed by S-100 and MT1 antibody staining, and was treated with pulse steroids and several pleural drainages, until the boy died after a large bilateral pneumothorax.