Bone histologic response to deferoxamine in aluminum-related bone disease

We have examined the changes in bone histology in 28 uremic patients after long-term treatment with the aluminum chelator, deferoxamine. Marked declines in stainable bone-surface aluminum were associated with increases in bone formation rate and osteoblastic osteoid following deferoxamine. The increased bone formation resulted from increases in bone apposition and length of double-tetracycline labels, the latter being highly correlated with the increase in osteoblastic osteoid (r = 0.85). While bone surface aluminum was highly correlated with bone formation rate (r = .69, p less than .001), bone aluminum content did not correlate with bone formation (r = 0.13) and was often elevated after treatment despite an improvement in bone histology. Patients who had undergone prior parathyroidectomy were less likely to have improved bone histology than those with intact parathyroid glands. We conclude that aluminum chelation therapy with deferoxamine is effective in ameliorating the bone histology of patients with chronic renal failure and bone aluminum accumulation, and that the change in stainable bone-surface aluminum is a more sensitive indicator than the change in bone aluminum content in assessing adequacy of chelation therapy. Patients who need deferoxamine treatment but have undergone a prior parathyroidectomy will probably require a more intensive treatment schedule than those who have intact parathyroid glands.