Risk stratification nomogram for nephropathy after abdominal contrast-enhanced computed tomography.
OBJECTIVE
Abdominal contrast-enhanced computed tomography (A-CECT) is widely used in emergency departments despite the risk of contrast-induced nephropathy. We attempted to develop a risk stratification nomogram for nephropathy in patients receiving emergency A-CECT.


METHODS
Seven hundred fifty patients who received emergency A-CECT between August 2003 and January 2007, with available serum creatinine (SCr) measurements before and after A-CECT were included. Nephropathy was defined as either an absolute increase of 0.5 mg/dL or greater (44 μmol/L) or a relative increase of 25% or more in the SCr from baseline. A nomogram was developed based on multivariate logistic regression analysis using clinical variables available before A-CECT. The model was internally validated with a bootstrapping method, and performance was assessed by area under the receiver operating characteristics curve (AUC) and calibration curve.


RESULTS
Nephropathy was observed in 34 of 750 patients. A nomogram was developed using age (odds ratio, 1.04 per 1-year increment) and baseline SCr (odds ratio, 2.51 per 1-mg/dL increment) as risk factors. Diagnostic accuracy of the model was fair by bias-corrected calibration plot. The AUC of the model was 0.794 (95% confidence interval, 0.734-0.854), and the AUC with bootstrapping samples of 200 repetitions was 0.794 (95% confidence interval, 0.737-0.851).


CONCLUSIONS
The risk of nephropathy after emergency A-CECT can be individually predicted by internally validated nomogram using clinical variables available before the procedure.
Kim
Kyung Su
KS
Department of Emergency Medicine, Seoul National University Hospital, Seoul, Korea.
Kim
Kyuseok
K
Hwang
Seung Sik
SS
Jo
You Hwan
YH
Lee
Christopher C
CC
Kim
Tae Yun
TY
Rhee
Joong Eui
JE
Suh
Gil Joon
GJ
Singer
Adam J
AJ
Kim
Hye Duk
HD
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D007472:Iohexol / Q000009:adverse effects / Q000031:analogs & derivatives; D007479:Iopamidol / Q000009:adverse effects / Q000031:analogs & derivatives; D007674:Kidney Diseases / Q000139:chemically induced* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D049451:Nomograms; D011237:Predictive Value of Tests; D012372:ROC Curve; D011860:Radiography, Abdominal / Q000009:adverse effects*; D018570:Risk Assessment; D012307:Risk Factors; D014057:Tomography, X-Ray Computed / Q000009:adverse effects*
D003287:Contrast Media; C057937:iomeprol; D007472:Iohexol; C038192:iopromide; D003404:Creatinine; D007479:Iopamidol