Dialysis osteomalacia: clinical aspects and physiopathological mechanisms

Dialysis osteomalacia is characterized by distinctive, although not pathognomonic, clinical and biochemical features. Symptoms and signs may include musculoskeletal pain, arthralgias, proximal muscle weakness, and spontaneous fractures. Biochemical characteristics may be hypercalcemia and normal serum alkaline phosphatase activities. Vitamin D administration may induce early severe hypercalcemia. Plasma phosphate and immunoreactive parathyroid hormone concentrations may be at any level. Only bone histology allows to establish the diagnosis of dialysis osteomalacia with certainty. Diphosphonate bone scan, however, enables to distinguish between severe osteitis fibrosa and dialysis osteomalacia. The diagnostic value of desferrioxamine administration with subsequent measurement of plasma aluminium remains to be determined. The complex interactions existing between parathyroid hormone and aluminium are not yet fully understood.