Agnogenic myeloid metaplasia and spinal cord compression.

A 55-year-old White male with agnogenic myeloid metaplasia, proved on bone marrow trephine biopsy, underwent splenectomy for abdominal discomfort. Six months later he developed paraparesis and on myelography multiple extradural obstructions were seen. In the absence of other obvious diagnostic possibilities, these were attributed to areas of extramedullary haematopoiesis, and he was treated with local radiotherapy. However, the neurological deficit progressed and emergency laminectomy and decompression were undertaken. Tissue obtained at this time confirmed the diagnosis of agnogenic myeloid metaplasia. A repeat myelogram showed complete relief of the obstruction, but the patient developed fulminating septicaemia and died. These findings are reported in view of the great rarity of spinal cord compression due to multiple areas of extramedullary haematopoiesis.