ESPN 54th Annual Meeting

ESPN 2022


 
FGF23, iron status and anemia in children with chronic kidney disease
VASILIKI KARAVA 1 JOHN DOTIS 1 ANTONIA KONDOU 1 ATHANASIOS CHRISTOFORIDIS 2 ANNA TAPARKOU 3 EVANGELIA FARMAKI 3 MARINA ECONOMOU 4 NIKOLETA PRINTZA 1

1- PEDIATRIC NEPHROLOGY UNIT, 1ST DEPARTMENT OF PEDIATRICS, HIPPOKRATIO GENERAL HOSPITAL, ARISTOTLE UNIVERSITY OF THESSALONIKI, GREECE
2- PEDIATRIC ENDOCRINOLOGY UNIT, 1ST DEPARTMENT OF PEDIATRICS, HIPPOKRATIO GENERAL HOSPITAL, ARISTOTLE UNIVERSITY OF THESSALONIKI, GREECE
3- PEDIATRIC IMMUNOLOGY AND RHEUMATOLOGY REFERRAL CENTER, 1ST DEPARTMENT OF PEDIATRICS, HIPPOKRATIO GENERAL HOSPITAL, ARISTOTLE UNIVERSITY OF THESSALONIKI, GREECE
4- PEDIATRIC HEMATOLOGY UNIT, 1ST DEPARTMENT OF PEDIATRICS, HIPPOKRATIO GENERAL HOSPITAL, ARISTOTLE UNIVERSITY OF THESSALONIKI, GREECE
 
Introduction:

 This cross-sectional study investigates the association of fibroblast growth-factor 23 (FGF23) with iron status and anemia in children with moderate and advanced chronic kidney disease (CKD).

Material and methods:

 Serum calcium, phosphorus, 25(OH)D, intact parathormone, c-terminal FGF23 and a-Klotho were measured in 53 patients from 5 to 19 years old with GFR<60 ml/min/1,73m2. Serum iron (Fe), ferritin and unsaturated iron-binding capacity, blood Hb and red blood cell indices were measured the same day. Transferrin saturation (TS) was calculated for each patient.

Results:

 LnFGF23 was correlated to lnKlotho (rs=-0.321, p=0.020) after adjustment for CKD stage. In 36 patients with CKD stage 3-4, lnFGF23 was correlated to Fe (rs=-0.415, p=0.013) and TS (rs=-0.356, p=0.036) but not to ferritin (rs=0.062, p=0.725) after adjustment for CKD stage. In CKD stage 5 patients, no correlation was observed between lnFGF23 and iron parameters. No correlation was observed between lnKlotho and iron parameters in both patient groups. In CKD stage 3-4 patients, TS was correlated to Hb (rs=0.465, p=0.004), red blood cell mean corpuscular volume (rs=0.360, p=0.031) and distribution width (rs=-0.392, p=0.018). In this patient group, 10 patients presented low Hb, 8 of which also presented low TS (<16%). In multivariate backward logistic regression analysis, lnFGF23 was associated with low TS and low Hb, after adjustment for bone mineral parameters and CKD stage (OR 4.402, 95% CI 1.118-17.336, p=0.034 and OR 5.145, 95% CI 1.039-25.487, p=0.045 respectively).

Conclusions:

 In pediatric CKD stages 3-4, FGF23 is possibly implicated in the disturbed iron metabolism and consequent anemia, independently of Klotho.