Is aluminum related bone disease common in hemodialysis units using aluminum based phosphate binders?

The extent of aluminum related bone disease was evaluated in 41 patients on regular maintenance hemodialysis in two dialysis centers in Riyadh, Saudi Arabia. There were 22 males and 19 females aged 20 to 70 years (mean 35.5+11.2 years). Thirty eight of the patients were on aluminum based oral phosphate binders. Investigations performed included serum calcium, magnesium, aluminum and parathormone and radiological investigations including skeletal survey and dual photon absorptiometry. All the patients underwent bone biopsy and the biopsy material was subjected to morphometric studies, including staining for aluminum deposits. The patients were divided into two groups: group 1, (16 patients, 39%) with negative aluminum staining in the bone biopsy tissue, and group 2, (25 patients, 61%) with positive aluminum staining. Bone pain and its distribution as well as fractures were similarly prevalent in both groups. The levels of aluminum in the blood was significantly higher in group 2 (32.9 + 20.2 vs 17.9 + 11.2 ug/L P< 0.05), though it was lower than the lowest accepted toxic level (40 ig/L). There was no significant difference between the two groups in the biochemical or hormonal data, frequency of abnormal radiological signs and pattern of bone histology. Our study indicates that increased aluminum deposition in the bone is prevalent in patients on maintenance hemodialysis using aluminum based phosphate binders, but adynamic bone disease is not prevalent. Further studies may be needed on a larger scale to assess the magnitude of the problem.