Bone biopsy results and serum bone turnover parameters in uremic children

Abstract

The aim of the study was to evaluate the prevalence of renal osteodystrophy types in children undergoing haemodialysis and continuous ambulatory peritoneal dialysis and to assess the usefulness of biochemical parameters in diagnosis of renal osteodystrophy. Bone biopsy and measurements of serum parathormone (iPTH) level, alkaline phosphatase (AP), osteocalcin (OC), procollagen 1C, calcium and phosphorus levels were performed in 51 children aged 11.5 ± 2.9y with end-stage renal failure. Renal osteodystrophy (ROD) was diagnosed as follows: adynamic bone disease (ABD) in 14 (27%); normal bone histology (NB) in 19 (37%), osteomalacia (OM) in 1 (2%), mixed lesion (Mix) in 5 (10%) and hyperparathyroidism (HP) in 12 (24%) children. There was no difference in prevalence of ROD types between children on CAPD and HD. We found significant differences in the mean value of iPTH, OC levels and AP activity in HP vs NB and HP vs ABD. The prevalence of ABD was significantly higher in patients with PTH below 50 pg/ml than in patients with PTH above 50 pg/ml (p < 0.05). In 69% of children with NB the iPTH level was between 50 and 150 pg/ml. Most HP cases (75%) were diagnosed in patients with iPTH above 200 pg/ml. A high correlation between BFR and iPTH, BFR and OC, AP levels was found. Conclusion: The biochemical markers of bone turnover have only limited value in the differentiation of renal osteodystrophy types.