Non Invasive Diagnosis to Predict Adynamic Bone Disease in Haemodialysed Patients

Abstract

Precise evaluation of the underlying type of bone disease in hemodialysed patients frequently requires bone histomorphometry (including static and kinetic variables after double tetracycline labeling) which is an invasive and costly method. Due to the prevalence of adynamic bone disease in hemodialysis patients, different biochemical non invasive markers such as (serum intact osteocalcin, serum intact parathyroid hormone (iPTH) and bone specific alkaline phospha- tase (bAP) have been shown to be helpful in differentiation between low and high bone turnover. Our study was conducted to detect the usefulness of measuring serum intact osteocalcin and its correlation with serum iPTH and bAP to distinguish adynamic bone disease from other forms of renal osteodystrophy in hemodialysed patients. The study included 60 patients and 20 normal control subjects, presented at renal dialysis units, Ain Shams University hospitals. The hemodialysed patients were classified according to the results serum iPTH and bAP into two groups :  Group I : Included 18 patients (30%) with serum iPTH level 150 pg/ml and serum bAP  27 ng/ml.  Group II : Included 42 patients (70%) with serum iPTH level > 150 pg/ml and serum bAP > 27 ng/ml. The serum level of intact osteocalcin was measured for the control group and for all hemodialysed patients. The results revealed highly significant stastical differences in serum level of intact osteocalcin between all patients group and the control subjects being lower in control group. Also, the results revelaed that 30% of all patients group had adynamic bone disease and comparison between serum level of intact osteocalcin in adynamic bone disease group versus other patients group was highly significant, being higher in other patients group. There was no significant difference between adynamic bone disease patients and other patients as regard serum phosphorus, and serum calcium but there was a sigificant difference as regard age, while highly significant difference as regard sex, duration of hemodialysis, serum intact osteocalin, iPTH and bAP. These results suggest that combined estimation of serum iPTH, serum intact osteocalcin, and bAP can provide a useful information on the bone status in uremic patients and repesent reliable non invasive diagnostic tools for the prediction of adynamic bone disease.