Link between CT contrast agents, kidney injury may be overstated

Concerns about the connection between the use of intravenous contrast agents for CT scans and acute kidney injury may be overstated, according to new research from the Mayo Clinic.

In a study published recently in Radiology, researchers looked at more than 100,000 CT scans performed at Mayo between 2000 and 2010, They found that patients who received intravenous contrast agents, as well as those who didn't, had similar risks of developing acute kidney injury, otherwise known as contrast-induced nephropathy.

"These studies have significant clinical ramifications with regard to who is eligible to receive contrast media during CT exams," lead co-author Bob McDonald, a radiologist at Mayo, said according to an announcement. "Despite limited clinical evidence, contrast is commonly withheld during CT exams of individuals with even modest renal impairment due to concern for kidney injury, often at the expense of diagnostic accuracy of the exam.

"Our goal for these studies was to provide better evidence regarding the true incidence of renal injury following intravenous contrast administration and better define the 'at-risk' patient population."

Co-author Jennifer McDonald, a radiology associate at Mayo, said that if contrast-induced nephropathy exists, it is likely rare and not easily identifiable from unrelated causes of renal injury. "Hopefully our findings can promote additional research to help redefine the safety window of contrast media and, in turn, improve patient care through more frequent use of appropriate clinical imaging," she said.

To learn more:
- see the study abstract
- read the announcement