[Somatotropic axis and molecular markers of mineral metabolism in children undergoing chronic peritoneal dialysis].

Growth failure is one of the most relevant complications in children with chronic kidney disease (CKD). Among others, growth hormone (GH) resistance and bone mineral disorders have been identified as the most important causes of growth retardation.

OBJECTIVES: 1. To characterize bone mineral metabolism and growth hormone bio-markers in CKD children treated with chronic peritoneal dialysis (PD). 2. To evaluate height change with rhGH treatment.

PATIENTS AND METHOD: A longitudinal 12-month follow-up in prepuberal PD children.

EXCLUSION CRITERIA: Tanner stage >1, nephrotic syndrome, genetic disorders, steroids, intestinal absorption disorders, endocrine disturbances, treatment with GH to the entry of the study. Demographic and anthropometric data were registered. FGF23, Klotho, VitD, IGF-1, IGFBP3, and GHBP were measured to evaluate mineral and growth metabolism.

RESULTS: 15 patients, 7 male, age 6.9±3.0 y were included. Time on PD was 14.33±12.26 months. Height/age Z score at month 1 was -1.69±1.03. FGF23 and Klotho: 131.7±279.4 y 125.9±24.2pg/ml, respectively. 8 patients were treated with GH during 6-12 months, showing a non-significant increase in height/age Z-score during the treatment period. Bivariate analysis showed a positive correlation between Klotho and delta ZT/E, and between GHBP vs growth velocity index (p<.05).

CONCLUSIONS: FGF23 values were high and Klotho values were reduced in children with CKD in PD, comparing to healthy children. Somatotropic axis variables were normal or elevated. rhGH tends to improve height and there is a positive correlation of GHBP and growth velocity in these children.