Lumbosacral extradural extramedullary hematopoiesis in thalassemia major causing spinal canal stenosis

Abstract

Background: Extramedullary hematopoiesis (EH) is common in patients with ineffective erythropoiesis like thalassemia major (TM). EH commonly involves intra-abdominal organs (e.g., spleen and liver), but rarely involves vertebral bodies. Here, we reviewed images of EH contributing to spinal canal stenosis.

Case description: A 19-year-old male with beta-thalassemia major (TM) presented with pain and bilateral lower extremity neurogenic claudication. Bilaterally, on examination, he had positive straight leg raising to 30°, a loss of the Achilles responses, and decreased pain appreciation in the L5S1 distributions. The lumbar MR showed anterior epidural lobulated mass lesions at L5 and S1, contributing to marked canal stenosis. Following an L5/S1 laminectomy for decompression, the biopsy revealed extramedullary hematopoietic tissue.

Conclusion: Patients presenting with the lower extremity symptoms/signs, ranging from low back pain to neurogenic claudication and even paraplegia, may have EH secondary to TM. Treatment options include hypertransfusion, local radiation therapy, and/or surgical decompression.

Keywords: Beta-thalassemia; Extramedullary hematopoiesis; Radiculopathy; Spinal stenosis.

Figure 1:

(a and b) Sagittal T2-weighted images showing L5, S1 level anterior epidural hypointense lobulated mass lesion attached to the posterior surface of the vertebral body with severe canal stenosis. (c and d) Axial T2-weighted images showing bi-lobulated lesion protruding from the vertebral body with near total canal stenosis.