Identification of Prognostic Urinary Biomarker for Acute Kidney Injury in Preterm Infants by Proteomics

Clinical definitions of acute kidney injury (AKI) have been based on an increase in serum creatinine and a decrease in urine output. However, applying this definition to neonates remains challenging because of the normal renal physiologic features that serum creatinine levels are expected to increase in the first days after birth, and impaired sodium reabsorption and concentrating ability. Because of several limitations of early detection of AKI, investigators are focused on identifying biomarkers that predict AKI before an increase serum creatinine level. Investigators will collect urine from preterm infants before and after administrating ibuprofen for closing patent ductus arteriosus. To identify novel biomarkers, investigators will analyze urine by proteomics. To verify those biomarkers, investigators will use initial urine on the first day of life from preterm infants who diagnosed AKI within 7 days after birth without any risk factors for AKI and enrolled institutional bio-repository.