Assessment of serum osteocalcine level in pre-dialysis patients with chronic renal failure.
The application of serum osteocalcine as a marker of osseous synthesis in patients with renal osteodystrophy is still disputable because of its predominantly renal excretion. The aim of the present study was to investigate the level of serum osteocalcine in pre-dialysis patients with chronic renal failure (CRF).


METHODS
47 patients aged 22-60 years (26 males and 22 females) with chronic renal failure were studied. 23 of them were stage I CRF patients (creatinine up to 353.6 mumol/l) and 24 were stage II and III CRF patients (creatinine up to 800 mumol/l). 35 healthy subjects (15 males and 20 females) were used as controls. Serum osteocalcine was measured by a radioimmunologic assay (ELSA-OSTEO-CIS, France). Serum creatinine, calcium, phosphorus and alkaline phosphatase were detected on a biochemical analyzer "Optima" (Kone Instruments, Finland) using the standard techniques recommended by IFCC.


RESULTS
Serum osteocalcine was significantly elevated in patients with stage I CRF (45.61 +/- 7.75 ng/ml), compared to the control group (14.61 +/- 1.02, p < 0.001; u = 3.96). A significant increase was also found in patients with stage II and III CRF (120.48 +/- 15.96 ng/ml, p < 0.001; u = 4.22). No significant difference in osteocalcine level was found between male and female patients (83.77 +/- 15.09 vs. 94.52 +/- 16.88). 32 (68%) patients of the entire sample had osteocalcine above the reference values. These included 11 out of 23 patients with stage I CRF (47%) and 21 out of 24 patients with stage II and III CRF (87%). A moderately positive correlation was established between osteocalcine level and the duration of CRF (0.57), as well as between serum creatinine (0.39) and phosphorus (0.34). A moderately negative correlation was discovered between creatinine clearance (-0.42) and total serum calcium (-0.37).


CONCLUSIONS
Serum osteocalcine could be used as a marker for bone synthesis in pre-dialysis patients with CRF. Our results indicate that more than 50% of the patients show evidence for renal osteodystrophy.
Kumchev
E P
EP
Department of Nephrology, Higher Medical Institute-Plovdiv, Bulgaria.
Stanchev
V L
VL
Yaneva
M P
MP
Botushanova
A D
AD
Dimitrova
R H
RH
Dimitrakov
D J
DJ
D000328:Adult; D002118:Calcium / Q000097:blood; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood*; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood*; D010758:Phosphorus / Q000097:blood; D012016:Reference Values
D015675:Osteocalcin; D010758:Phosphorus; D003404:Creatinine; D002118:Calcium