FIBROBLAST GROWTH FACTOR 23 AS EARLY MARKER OF MINERAL AND BONE DISORDER IN PATIENTS WITH CHRONIC KIDNEY DISEASE

The aim: to study the state of regulation of mineral metabolism in CKD by evaluating the serum concentration of c-terminal FGF-23, PTH, Ca, P, and to investigate the relationship between FGF-23 and PTH in CKD. Materials and methods. The study involved 106 people with CKD, 47women (44%) and 59men (56%) aged (49.6 ± 13.9) years. The C-terminal FGF-23 fragment was determined using a set of reagents for the enzyme immunoassay «Biomedica». The glomerular filtration rate (GFR) was calculated using the CKD EPI formula (KDIGO 2012). Results. A progressive increase in PTH levels was observed in parallel with the development of renal insufficiency in patients with CKD. Beginning with the CKD stage III, a significant increase above the norm (p <0.05) in the level of PTH ((85.79 ± 29.3) pg / ml) was observed. A progressive increase in the serum concentration of the c-terminal fragment of FGF-23 in patients with CKD was observed along with the GFR decrease. Statistically significant (p <0.05) increase in the concentration of FGF-23 was observed in CKD stage II ((1.29 ± 0.08) pmol / L) compared with CKD I ((0.76 ± 0.07) pmol / L). A strong negative association was found between FGF-23 and GFR (r = -0.87, p <0.05) in CKD. The existence of a strong direct association (r = 0.84, p <0.05) between the level of PTH and FGF-23 in CKD was established. Conclusions. Growth of the level of FGF-23 outstrips the increase in PTH in the time interval by 1 stage of CKD. C-terminal FGF-23 can be used as an early marker of the development of mineral disturbances in patients with CKD.