Parathyroidectomy in chronic renal failure.

In order to establish whether parathyroidectomy altered the natural history of ectopic calcification in patients with renal failure we undertook a detailed analysis of 62 patients with hyperparathyroidism secondary to chronic renal failure who were submitted to parathyroidectomy. Biochemical data (61 patients) and radiological skeletal surveys (42 patients) were studied before and after parathyroidectomy. Transiliac bone biopsies were obtained at (or some time in the previous six months before) parathyroidectomy in 30 and in 36 patients after surgery. Paired bone biopsies were available from 17 of these patients. In the majority of patients secondary hyperparathyroidism was controlled after parathyroidectomy although in seven patients (11 per cent), who underwent subtotal parathyroidectomy, it relapsed after initial improvement. Non-visceral soft tissue calcification disappeared or decreased in 60 per cent of the patients after parathyroidectomy. However, despite marked improvement in subperiosteal erosions and histological osteitis fibrosa, with significant reductions in iPTH and Ca X P product after parathyroidectomy, small peripheral arterial calcification developed or progressed in 56 per cent of the patients. Histological osteomalacia after parathyroidectomy developed after operation in two patients. Both had positive aluminium stains for excess aluminium in their bone. Numbers of osteoclasts and the amount of marrow fibrosis declined in parallel following parathyroidectomy, but woven bone persisted for months or years.