News

Intravascular contrast dyes, used in such common tests as coronary angiographies, are safe for the majority of people. However, approximately eight percent of patients experience acute kidney injury (AKI), because of the dyes. Dr. Matthew James MD, PhD, and Dr. Dan Muruve, MD, collaborators on a Canadian Institutes of Health Research (CIHR) team focused on inflammation and kidney disease, shows for the first time how contrast dye injures the kidney in a study published recently in the Journal of Clinical Investigation 

“[People] who require complex procedures with large contrast dye volumes, or those with pre-existing diabetes or chronic kidney disease, have a much higher risk of acute kidney injury following these procedures,” says Dr. James, a graduate of the Kidney Research Scientist Core Education Program (KRESCENT). “We have effective protocols to minimize that risk, but occasionally, in some high-risk patients, these measures are insufficient to completely prevent kidney damage. This research has shown how the kidney responds to the contrast dye and reveals new ways we could better protect the kidneys.”

The University of Calgary scientists have mapped the progression of the dye through the kidneys of mice in real time. The study shows that the dye gets flushed through a fully hydrated kidney, but gets absorbed by a low hydration kidney, causing inflammation that can lead to serious damage to the organ. This has already resulted in work with human subjects.

“We did a small study testing human urine after contrast dye exposure. We saw the same markers in people as we do in mice. These results can help us add to the steps we currently emphasize to reduce the amount of contrast dye used and to hydrate the patient,” says James. “Despite this, some patients with kidney disease currently avoid these medical tests because of the concern about possible injury to their kidneys. This research could help make these tests even safer for them.”

“These findings offer new hope to drastically reduce future instances of kidney failure caused by injury,” says Elizabeth Myles, National Executive Director, The Kidney Foundation of Canada. “It is very gratifying and exciting to see how funded research can lead to tangible results that help prevent kidney disease, ease its burden, and brings us another step closer to a cure.”

The research team is now working on a therapeutic intervention to help those who cannot be hydrated easily. “For some patients, with weak hearts, extra fluids are not recommended,” says Muruve. “Through this research we’ve discovered a drug that stops the kidney from absorbing the dye to prevent possible injury. We’ve tested a medication that is showing promising results. The next step is to translate these findings into clinical trials.”

About the Kidney Research Scientist Core Education Program (KRESCENT)

The Kidney Research Scientist Core Education and National Training Program, (KRESCENT) is a unique training initiative aimed at enhancing kidney research capacity in Canada. KRESCENT is a multi-partner collaboration, founded by The Kidney Foundation of Canada, the Canadian Society of Nephrology, and the Canadian Institutes of Health Research.