A research reported that every year in the U.S. thousands of neonates die because of acute kidney injury (AKI) characterized by impaired kidneys function. Patricio Ray, M.D. described that it was difficult to recognize the primary stages of AKI in neonates.

Large volumes of fluids must not be administered to AKI neonates because this may result in severe problems when the kidneys work improperly. Lacking standard definition for AKI led to confusion, Dr. Ray reported. For instance, numerous studies assessed the percentage of neonates in NICUs with AKI (8% to 40%) based on which definition was used.  

In 2012, the Kidney Disease Improved Global Outcome (KDIGO) group issued practice guidelines for AKI that provided a standard followed by doctors and scientists. They measured the relative levels of serum creatinine (filtered by the kidneys) and the urine output volume. However, the guidelines were not satisfactory to recognize neonates experiencing the initial stages of AKI during the first week of life.

Neonates may have high serum creatinine levels during the first week of life as residual levels are transferred from mothers through the placenta and their kidneys are immature.

In 2013, the National Institute of Diabetes and Digestive and Kidney Diseases, discussed a study that evaluated advanced information about AKI in neonates and evaluated the method to measure kidney function in neonates. It was observed that 106 neonates with hypoxic ischemic encephalopathy (HIE) condition in which the brain doesn't receive sufficient oxygen, significantly increased the AKI risk.

Around 69% of the neonates with HIE surveyed at Children's National Health System did not develop kidney failure condition during the first week of life while their serum creatinine concentrations decreased by 50 % or more as found in healthy neonates. 

In other 12% of the neonates with HIE who developed AKI, mechanical ventilation and medications that increased the blood pressure were required. Higher levels of antibiotics in bloodstreams; retained fluid; decreased flushing of molecule by their kidneys was found which required hospitalization for a longer period.

In 19% of the neonates with HIE, the standard criteria for AKI were not met. They had decreased rate of serum creatinine, considerably slower than the normal neonates and the neonates with HIE who had excellent results. Their results related to infants with established AKI.

Doctors could recognize neonates with impaired kidney function based on the rate of serum creatinine decline during the first week of life. This is significant method to recognize the primary stages of AKI in neonates.

Dr. Ray said, "By looking at how fast babies were clearing their serum creatinine compared with the day they were born, we could predict how well their kidneys were working".

Advance studies are essential to confirm the efficacy of the innovative approach, to evaluate the kidney function of term neonates with other diseases and preterm neonates and it should be standard in clinical practice.