Vertebral compression fractures at the onset of acute lymphoblastic leukemia in a child.

Abstract

A child with acute lymphoblastic leukemia, spinal osteoporosis with vertebral compression fractures, and hypercalcemia appearing early in the course of the hematologic disease was followed for two and a half years. Bone mineral density (BMD), measured by single photon absorptiometry at the radial shaft, was within normal limits for age and sex. However, x-rays of vertebrae and vertebral BMD, measured by dual photon absorptiometry, showed marked demineralization. Despite leukemic remission, the spinal osteoporosis became worse and the patient required aggressive treatment for eight months. Treatment included 50 units of calcitonin subcutaneously every other day, 1,000 mg/day of oral calcium, and 3,000 IU/day of vitamin D. The back pain disappeared quickly, and laboratory controls showed a significant diminution of bone turnover. No new compression fractures occurred. Eighteen months later, the patient continued in remission and menarche had occurred. Dual photon absorptiometry revealed a significant "catch up" of the lumbar spine BMD. X-ray examination showed a marked remodeling of the vertebral bodies. BMD measurements in this child indicate that bone loss affected the trabecular bone compartment or occurred only at active bone marrow sites. The rapid clinical amelioration and objective biochemical, densitometric, and radiologic evidence of bone improvement warrant further clinical trials on similarly affected patients.