Biomarkers warn of kidney injury after heart surgery

Heart surgery is tough enough, without anything else going wrong, but for some people the lack of blood flow during the operation can damage their kidneys. A new biomarker could help pick out those patients most at risk and allow doctors to take steps to protect their kidney function.

Because the blood supply is cut off or restricted for a long period during some forms of heart surgery, this can cause acute kidney injury. This usually sorts itself out, but it may lead to the kidney gradually, or even quickly, losing function. To try to find biomarkers to predict which patients might be at risk, U.S. researchers looked at a range of biomarkers in blood and urine samples from 380 people who had heart surgery and developed acute kidney injury, in the Translational Research Investigating Biomarker Endpoints in AKI study (TRIBE-AKI).

The three biomarkers linked with poor outcomes were urinary IL-18, urinary albumin-to-creatinine ratio (ACR) and plasma neutrophil gelatinase-associated lipocalin (NGAL).

"Our multi-center study is the largest acute kidney injury biomarker study performed to date in adults," said Dr. Chirag Parikh of Yale University, one of the authors. "Future studies can build on this work and use these markers to enroll patients who are at a high risk for AKI and its associated complications into clinical trials of promising therapies," he added.

Measuring these biomarkers on the day that patients are diagnosed with acute kidney injury would help identify the patients who are at risk of progression using a simple blood or urine test, so that they could be supported and counseled, and could be monitored more closely and receive treatment at an earlier stage.

- read the press release
- see the abstract in the Journal of the American Society of Nephrology
- check out the article in MedPage Today