[Pathological analysis of renal osteodystrophy in 194 cases]

Renal osteodystrophy is a metabolic bone disease resulted from chronic renal failure. The long-standing alterations in a mineral metabolism generated by renal failure have a profound effect on the skeleton and induce severe systemic metabolic bone disease. Iliac crest biopsies of 194 patients of chronic renal failure were taken and among them 10 cases were examined for Calcium(Ca), phosphorus (p), parathyroid hormone (PTH), 1,25(OH)2D3 and aluminium (Al). The histological bone changes are characterized by development of osteitis fibrosa, increase of bone resorption and the number of osteoclast, increase of osteoid volume (osteoblastic osteoid and acellular osteoid), active remodelling of bone and aluminum deposition in the bone. According to histological appearance, advanced renal bone disease could be subdivided into three groups namely: Secondary hyperparathyroid bone disease (high turnover uremic osteodystrophy), osteomalacia (low turnover uremic osteodystrophy) and mixed uremic osteodystrophy consisting of mild to moderate hyperparathyroid bone disease and defective mineralization. Aluminum-related bone changes might be obtained in various extent in all these groups. Although this classification does not fully represent all the separated entities, and there is also transformation from one form to another, it seems no less significant as a reference for clinical considerations.