Prevalence of Hyperparathyroidism, Mineral and Bone Disorders in Children with Advanced Chronic Kidney Disease

Objective To identify the prevalence and risk factors for secondary hyperparathyroidism in children with advanced stages of chronic kidney disease (CKD). Methods A retrospective cross-sectional observational study of clinical and laboratory data of pediatric patients with CKD stage 3, 4 was conducted from 2005 through 2013 at a single center in the Kingdom of Saudi Arabia. Results One hundred nineteen children (60.5 % boys) with mean age of 10.1 +/- 5.1 y were included in the study. The mean eGFR (estimated Glomerular Filtration Rate) was 18.3 +/- 15.4 ml/min/1.73m(2) and the mean intact parathyroid hormone (iPTH) level was 62.2 +/- 89.4 pmol/L. Patients with a high iPTH had lower eGFR than those who were euparathyroid (16 +/- 13.4 vs. 29.7 +/- 19 ml/min/1.73m(2), respectively; p = 0.006), had lower calcium levels (2.2 +/- 0.3 vs. 2.4 +/- 0.3 mmol/L; p = 0.03) and a lower bicarbonate level (21.2 +/- 4.2 vs. 23.3 +/- 3.2 mmol/L; p = 0.04). Three children with hyperparthyrodism (4.9 %) had fractures, 16 (26.2 %) had bone deformities compared to 5 in the euoparathyroid group (p = 0.012). Parathyroid hormone negatively correlated with the patient's eGFR (r = -0.55), serum calcium (r = -0.43), and positively correlated with serum phosphate (r = 0.38). Conclusions The single most important predictor of hyperparathyroidism in children in the present sample was eGFR.