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.