Joachim Hohmann MD, DIPLPHYS, Abstract Co-Author: Research funded, Bayer AG Research funded, Siemens AG

Caroline Newerla, Abstract Co-Author: Nothing to Disclose

Silke Potthast MD, Abstract Co-Author: Research grant, Bayer AG

Georg M. Bongartz MD, Presenter: Research grant, Bayer AG Research Consultant, Siemens AG Research Consultant, Guerbet SA Research Consultant, Bracco Group

Patients with reduced renal function have a higher risk of CMIN and/or NSF. To select these patients the ACR and the ESUR proposes a questionnaire and consecutive measurements of serum creatinine prior to the application of a contrast agent in CT and MRI examinations. The aim of the study was to find out how the proposed approach performs.

1385 patients (f=724, m=661, mean age: 56y) were requested to fill out a questionnaire prior to a contrast administration in CT (n=300) or MRI (n=1085). Creatinine measurements were performed when one or more questions concerning previous renal diseases (including surgery), known diseases in relatives, history of diabetes, proteinuria, hypertension, gout and analgetic medication were positive. Patients with diabetes and hypertension were additionally asked for treatment. Statistical evaluation was done using the Fisher test and calculating the odds ratio (OR) for each question.

Of the 1385 patients 497 (36%) gave one ore more positive answers to the questionnaire. Of these 68 (14%) had an elevated creatinine level (f>96 umol/l; m>110 umol/l). 18 patients (4%) had a creatinine level of above 150 umol/l of which 4 (0.8%) were waived the contrast agent administration. Only the question concerning a previous renal disease showed a significant relation to an elevated creatinine level (p=0.0011, OR=2.7). Comparing the groups with complete negative responses, with at least one positive response and with elevated serum creatinine levels we found a significant difference in the mean age (51±16y, 59±13y, 70±12y, p<0.0001). Looking at the subgroup with an age <=70y we found no relation of any of the questions to an elevated creatinine level.

Our investigation suggests that we should measure the creatinine in every patient older than 70y. For patients younger than 70y it seems reasonable to waive the recommended questionnaire at least in our population. However asking for previous renal diseases or treatment before applying a contrast agent is a matter of course.

To waive a questionnaire will save time and special effort in clinical practice. Any patient >70y should have a valid serum creatinine level.

Hohmann, J, Newerla, C, Potthast, S, Bongartz, G, Serum Creatinine Measurements: Evaluation of a Questionnaire according to the ACR Recommendations and the ESUR Guidelines.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11010825.html