[A case of multisystem Langerhans' cell histiocytosis with lung deterioration over 15 years].

We report a case of multisystem Langerhans cell histiocytosis (LCH) with lung, bone and pituitary involvement. A 20-year-old man developed thirst, polydipsia and polyuria in 1983. He had right femur pain from 1988 and osseous LCH was diagnosed based on the operated specimen in 1989. From July 1990, he had right chest pain on coughing and dyspnea and was admitted in November 1990. LCH involving the lungs was diagnosed by CT images and diabetes insipidus was also detected. Steroid therapy was started from 1991, but he discontinued it in 1998. Though he stopped smoking, his clinical symptoms worsened and he experienced bilateral pneumothoraces in 2002 and since then he has been receiving home oxygen therapy. Pulmonary LCH is thought to have a good prognosis, but in recent studies, its survival rate appears low. We report a case of multisystem LCH with lung deterioration over about 15 years.