OBJECTIVE. The objectives of our study were to develop a model to predict the prob�ability of reduced renal function after outpatient contrast-enhanced CT (CECT)�based on patient age, sex, and race and on serum creatinine level before CT or directly based on esti�mated glomerular filtration rate (GFR) before CT�and to determine the relationship between patients with changes in creatinine level that characterize contrast-induced nephropathy and patients with reduced GFR after CECT.
MATERIALS AND METHODS. Of 5,187 outpatients who underwent CECT, 963 (18.6%) had serum creatinine levels obtained within 6 months before and 4 days after CECT. The estimated GFR was calculated before and after CT using the four-variable Modification of Diet in Renal Disease (MDRD) Study equation. Pre-CT serum creatinine level, age, race, sex, and pre-CT estimated GFR were tested using multiple-variable logistic regression models to determine the probability of having an estimated GFR of
RESULTS. Significant (p
CONCLUSION. The probability of a reduced estimated GFR after CECT can be pre�dicted by the pre-CT estimated GFR using the four-variable MDRD equation. Furthermore, standard criteria for contrast-induced nephropathy are poor predictors of poor renal function after CECT. Criteria need to be established for what is an acceptable risk to manage patients undergoing CECT.