Contrast CT booked on three kidney screening questions, without a routine blood test beforehand

The recommendation. NICE NG148 (updated October 2024) says that before a non-urgent contrast CT the requester should use an eGFR from the past 6 months if there is one; if there is none, ask whether the person has kidney disease or a kidney transplant, has seen or is waiting to see a kidney specialist, kidney surgeon or urologist, or has symptoms of acute illness likely to cause acute kidney injury; and, if the answers do not suggest kidney disease and the person is clinically stable, consider proceeding "without the need for further blood tests before the scan" (1.1.10 to 1.1.12). The European ESUR 2026 handbook instead measures eGFR within 7 days for inpatients and the acutely ill and within 3 months for others, either in everyone or in those with a listed history.

Why it would matter. NICE's committee wrote that in current practice "a person is required to have an eGFR test in the 3 months before undergoing contrast media CT scanning", that this "often results in delayed scans", and that the change is likely to reduce eGFR testing and short-notice cancellations. People with cancer have many contrast scans, so each avoidable test and cancellation recurs.

Why it is untested. The same committee found the evidence for risk questionnaires "lacking in both quantity and quality" and made the recommendation on its own knowledge and expertise, with a research recommendation on validated tools. No study OnCo found measures how many trusts have adopted the questions, how many tests and cancellations they save, or how many people with unrecognised kidney impairment they miss.