Indirect methods for the diagnosis of aluminum bone disease: Plasma aluminum, the desferrioxamine infusion test, and serum iPTH

The diagnosis of aluminum bone disease is currently based on bone histomorphometry, which requires a bone biopsy. This procedure is invasive, has potential risk, albeit small, and may not be available for all dialysis patients. Therefore, the authors have evaluated a noninvasive test based upon the ability of desferrioxamine (DFO) to chelate tissue aluminum. A desferrioxamine chelation test, whereby urinary iron excretion is measured after the intravenous administration of desferrioxamine, has been used to estimate tissue levels of iron and has proven useful to identify patients with iron storage disease. An intravenous infusion of desferrioxamine can increase plasma aluminum levels by mobilizing tissue aluminum and may provide an index of tissue aluminum stores, particularly the bone aluminum content. The authors' results confirm their earlier observations that the DFO infusion test, which is easily performed, is noninvasive and well tolerated, can be useful in identifying patients with ABD. In certain cases, the test might obviate the need for a bone biopsy. Sequential DFO infusion tests during chronic chelation therapy may prove to be a useful index to monitor the decrease in tissue stores of aluminum.