Among the many post surgery complications, acute kidney injury (AKI) is the most common and preventable one which if neglected can advance to other severe complications or even cause fatalities. Acute kidney injury can be easily diagnosed by physicians with the use and development of biomarkers. In the two studies appearing in a forthcoming issue of the Journal of the American Society of Nephrology, researchers demonstrate that the risk of developing kidney injury subsequent to heart surgery can be evaluated by three protein measurements.
Study author, Chirag Parikh, MD, PhD from the Yale University School of Medicine, said: “To date, these are the largest studies in adults and children comparing and validating the performance of three of the most frequently studied markers of kidney injury.”
Over 1,200 adults and 300 children going through heart surgery all over North America were involved in the trial. The risk of developing kidney injury post surgery was evaluated by determining the levels of three proteins: urine interleukin-18 (IL-18), urine and plasma (blood) neutrophil gelatinase-associated lipocalin (NGAL) through regular collection of urine and blood samples.
Although a conventional technique of assessing kidney trouble is to determine the blood creatinine levels, this method is unsuitable because of delayed results and underestimation of early damage and injury to the kidneys.
Parikh said, “We demonstrated that the three proteins in our study identify kidney injury soon after surgery and 24 to 48 hours earlier than creatinine, and shows a similar result.”
Adults and children with the highest levels of urine IL-18 were at a more than six times higher risk of developing kidney injury. While kidney injury in adults was predicted by plasma NGAL, the same could not be accurately predicted through urine NGAL after adjusting the results for other factors. Unlike plasma NGAL, Urine IL-18 and urine NGAL were accurate indicators of kidney injury in children.
Doctors might want to identify which patients are at high risk of developing kidney injury by measuring these urine or blood proteins instantly after surgeries so that these patients benefit from kidney protective therapies.
Parikh is of the opinion that the diagnosis of kidney disease can be completely transformed by the findings of this study. He said, “Developing markers of structural kidney damage, before kidney function fails, is a top priority.”
The principal drawback of the research is that the study involved only Caucasian adults. Future studies are required to understand whether similar results will be obtained from studies in other races.