Neurodegenerative central nervous system disease as late sequelae of Langerhans cell histiocytosis. Report from the Japan LCH Study Group.

Clinical features, brain magnetic resonance imaging findings and EDSS scores of 11 patients with neurodegenerative central nervous system Langerhans cell histiocytosis were analyzed in Japan. All patients initially had multi-system-type Langerhans cell histiocytosis; 8 at 1-2 years of age and 3 at a later age. Neurodegenerative central nervous system Langerhans cell histiocytosis disease developed after a median time interval of 3.9 years from initial diagnosis. With a median follow-up of 4.5 years, 6 patients showed progression of disease with an EDSS score >3. This study demonstrates the importance of early detection of neurodegenerative central nervous system Langerhans cell histiocytosis by brain magnetic resonance imaging, particularly in the follow-up of patients who developed multi-system-type Langerhans cell histiocytosis in early infancy.