Ghrelin and Obestatin in CKD Children

This is a cross-sectional case-control study. Between January 2013 and June 2015 children and adolescents aged 5-20 years, referred to the Pediatric Nephrology, Dialysis and Transplant Unit of Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico - Milan, Italy were enrolled. Subjects with CKD stages II-V under conservative treatment (CKD-CT), or undergoing hemodialysis treatment (CKD-HD), or being renal transplant recipients (RTx) were included in the study. Data about age, primary renal disease and concomitant medications were collected for each subject. CKD stages were defined using the K/DOQI criteria of the US National Kidney Foundation. Control subjects were outpatients of the Pediatric Surgery Unit of the Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico - Milan, Italy, aged 1-20 years, who underwent a blood sample collection before a surgical intervention for the treatment of minor diseases that did not impair renal or endocrine function (i.e. phimosis, hydrocele, inguinal hernia). Biochemical and hormonal parameters Blood samples were collected between 7:00 and 8:00 a.m. after an overnight fast, and before dialysis in CKD-HD patients. Routine biochemical parameters \[creatinine, urea\] were measured in all subjects. Glomerular filtration rate was estimated (eGFR) by the Schwartz formula, with k = 0.413, as appropriate for standardized creatinine. In all subjects, plasma AG and UAG concentrations were measured by the Human Acylated / Unacylated Ghrelin ELISA kit (BioVendor, Laboratorni Medicina a.s., Brno, Czech Republic) according to manufacture procedures, and AG/UAG ratio was calculated. Serum obestatin concentrations were determined using the Human Obestatin ELISA kit (BioVendor, Laboratorni Medicina a.s., Brno, Czech Republic).