Primary intramedullary Langerhans cell histiocytosis of the thoracic spinal cord.

A 28-year-old male presented with a rare case of primary intramedullary spinal Langerhans cell histiocytosis (LCH) manifesting as the chief complaint of a 6-month history of gait disturbance and back pain, and difficulty with sphincter control. Serial T2-weighted magnetic resonance imaging of the thoracic spine revealed enlargement and intramedullary hyperintensity of the spinal cord at T2 to T4. Biopsy of the lesion was performed. Histological examination of the biopsy specimens verified vascular proliferation and remarkable infiltration of histiocytes that were positive for CD1a, suggesting a diagnosis compatible with LCH. The patient was treated successfully by steroid pulse therapy. LCH is a rare disease that occurs mainly in children and may cause a broad range of manifestations, from a single osseous lesion to multiple lesions involving more than one organ or system. The present case illustrates the unexpected occurrence and important differential diagnosis of primary intramedullary spinal LCH of the thoracic spine in adult patients presenting with progressive paraparesis and back pain.