Estimation of Kidney Function Through Combination of Renal Biomarkers in Blood and Urine of Healthy Infants and Children.

Despite relevant research in renal biomarkers, there is currently no optimal marker available that reliably quantifies kidney function and indicates kidney injury in its early stages. The combination of two or more biomarkers might be a more promising approach than investigating a single parameter. The relationship of renal biomarkers (creatinine, albumin, Cystatin C, NGAL, beta-trace protein, beta-2 microglobulin, and uromodulin) between each other and the variation over age in infants and children (without chronic kidney disease) is investigated.

The biomarkers in urine samples are explored to find less invasive means of quantifying renal health.

Patients between the age of 0 and 12 years undergoing blood with or without urine sampling as part of their diagnostic workup are eligible for the study. Unused residual blood and urine samples will be used for testing the renal parameters.

• blood test for renal biomarkers (creatinine, cystatin C, Neutrophil gelatinase-associated lipocalin, beta-trace protein, beta-2 microglobulin, uromodulin) (Other): relationship between the different biomarkers by linear regression analysis is assessed; influence of demographic variables (age, body weight, body surface area) is investigated by multivariate regression.
• urine test for renal biomarkers (creatinine, cystatin C, Neutrophil gelatinase-associated lipocalin, beta-trace protein beta-2 microglobulin, uromodulin, albumin) (Other): relationship between the different biomarkers by linear regression analysis is assessed; influence of demographic variables (age, body weight, body surface area) is investigated by multivariate regression.

Primary outcomes

• Serum concentration of creatinine (ymol/l) [single point in time at subject enrollment]: blood test for renal biomarker
• Serum concentration of cystatin C (mg/l) [single point in time at subject enrollment]: blood test for renal biomarker
• Serum concentration of Neutrophil gelatinase-associated lipocalin (ng/ml) [single point in time at subject enrollment]: blood test for renal biomarker
• Serum concentration of beta-trace Protein (mg/l) [single point in time at subject enrollment]: blood test for renal biomarker
• Serum concentration of beta-2 Microglobulin (mg/l) [single point in time at subject enrollment]: blood test for renal biomarker
• Serum concentration of Uromodulin (ng/ml) [single point in time at subject enrollment]: blood test for renal biomarker
• Urine concentration of creatinine (mmols/kg/24h) [single point in time at subject enrollment]: Urine test for renal biomarker
• Urine concentration of cystatin C (mg/l) [single point in time at subject enrollment]: Urine test for renal biomarker
• Urine concentration of Neutrophil gelatinase-associated lipocalin (yg/l) [single point in time at subject enrollment]: Urine test for renal biomarker
• Urine concentration of beta-trace Protein (mg/l) [single point in time at subject enrollment]: Urine test for renal biomarker
• Urine concentration of beta-2 microglobulin (mg/l) [single point in time at subject enrollment]: Urine test for renal biomarker
• Urine concentration of uromodulin (ng/ml) [at time of enrollment]: Urine test for renal biomarker
• Urine concentration of Albumin (mg/l) [at time of enrollment]: Urine test for renal biomarker
• Plasma protein binding of survival motor neuron (SMN) 2 splicing modifiers [single point in time at subject enrollment]: blood test for spinal muscular atrophy

Sex: All, ages: any to 12 Years, accepts healthy volunteers

Inclusion Criteria:

* healthy patients for elective surgery, requiring venous access via peripheral venous canula

Exclusion Criteria:

* chronic kidney disease
* acute kidney failure (stage 2 or above as defined by Kidney Disease Improving Global Outcomes (KDIGO) consensus 2012))
* sepsis
* shock
* major haemorrhage
* second or third degree burns
* liver failure
* chronic diseases with effecting the kidney (systemic lupus erythematosus, amyloidosis)

• Marc Pfister, Prof. Dr. MD, Principal investigator, University of Basel Children's Hospital

NIH grants: 2016