The new guidelines, which were published on 7 February in Acta Radiologica, take a more cautious approach compared to the European Society of Urogenital Radiology and the American College of Radiology.

The Swedish Society of Uroradiology said it adopted its approach as the actual risk of CI-AKI remains uncertain in patients with moderate to severe kidney damage due to a lack of prospective, controlled studies and the basis of retrospective, and propensity score-matched studies with low-grade evidence.

Another source of uncertainty is the imprecision of glomerular filtration rate (GFR) estimating equations, noted Dr. Ulf Nyman, from University of Lund, Malmö, and colleagues.

"However, randomized hydration studies indicate an upper limit risk of CI-AKI of about 5% for outpatients with a GFR in the range of 30-44 or 45-59 mL/min/1.73m2 combined with multiple risk factors. Apart from GFR limits, the guideline also includes limits for systemic contrast medium exposure expressed in gram-iodine/GFR ratio," they stated.