Spinal epidural extramedullary hematopoiesis with cord compression in a patient with refractory sideroblastic anemia. Case report.

Spinal cord compression by epidural extramedullary hematopoiesis (EMH) is a rare phenomenon. A case of acute compressive myelopathy is reported in a 72-year-old man with EMH secondary to sideroblastic anemia. Technetium colloid scanning was used to document extensive ectopic marrow formation. The patient improved following surgery and radiotherapy. A review of the literature revealed 23 other cases of symptomatic spinal epidural EMH. The underlying hematological disorder varied but was always of long duration. Eighty-eight percent of the patients were males. Symptoms lasted longer than 1 week in 90% of cases, and 91% demonstrated incomplete neurological deficits. Plain x-ray films were rarely helpful in establishing the diagnosis. Technetium sulfur colloid bone marrow scanning has been used successfully to detect EMH and has led to preoperative diagnosis in one case. Decompressive laminectomy with or without postoperative irradiation is the suggested therapy, although there is evidence that radiotherapy alone may be adequate in some cases. Good recovery is the rule despite long-standing neurological deficits.