Biomarkers assist in detecting life-threatening kidney injury after cardiac surgery

Following heart surgery, patients commonly experience acute kidney injury (AKI) and a progressive loss of kidney function. But a Yale-led study identifies specific blood and urine markers that can predict which patients will suffer these serious complications. The findings suggest that early detection and better patient monitoring could prevent kidney deterioration. The study appears online in the Journal of the American Society of Nephrology.

Acute kidney injury is a frequent complication of cardiac surgery that may lead to several adverse outcomes, including higher patient mortality. Previous studies have shown that several biomarkers can forecast early-onset AKI after cardiac surgery. However, most episodes of AKI are transient and will last only for a few days. Just 10 to 15 percent of patients will progress to severe AKI. Until now, there have been no effective tools to predict the risk of progressively worsening kidney function at the time of early-onset AKI. 

The Yale-led research team, along with researchers from other institutions in the United States and Canada, are known as the Translational Research Investigating Biomarker End-Points in AKI consortium (TRIBE-AKI), a multidisciplinary group of academic investigators with expertise in pre-clinical, translational, epidemiologic and health services research.

The TRIBE-AKI consortium evaluated blood and urine samples of 380 cardiac surgery patients on the day they were diagnosed with AKI, and found that one blood and two urine biomarkers (blood neutrophil gelatinase-associated lipocalin, urine IL-18, and urine albumin/creatinine ratio) forecast the future progressive deterioration in kidney injury as well as adverse patient outcomes.

“Daily monitoring of these biomarkers after cardiac surgery can provide us with an earlier window to intervene in cases where patients will have continued deterioration of their kidney function after surgery,” said lead author and principal investigator Chirag Parikh, M.D. Ph.D., director of the Program of Applied Translational Research and associate professor of nephrology at Yale School of Medicine and the Veterans Affairs Medical Center.

Other authors are Jay L. Koyner of the University of Chicago, Amit X. Garg and Heather Thiessen-Philbrook of the University of Western Ontario, Steven G. Coca and Kyaw Sint of Yale, Uptal D. Patel of Duke, and Michael G. Shilpak of the University of California San Francisco for the TRIBE-AKI Consortium.