BACKGROUND Although there has been considerable investigation of the general characteristics of contrast-induced nephropathy (CIN), it has not been studied adequately in a computed tomography (CT) population. We assessed the incidence and outcomes of CIN after contrast-enhanced CT in patients with chronic kidney disease pretreated with saline and N-acetylcysteine (NAC).

DESIGN Quality improvement report.

SETTING & PARTICIPANTS 520 patients registered in a CIN prevention program.

QUALITY IMPROVEMENT PLAN We initiated the CIN prevention program in January 2007. In this program, patients with chronic kidney disease undergoing contrast-enhanced CT in an outpatient setting were automatically referred to nephrologists, and patients received saline and NAC before and after CT. The development of CIN was assessed 48-96 hours after CT.

OUTCOMES Incidence of CIN and time to renal replacement therapy.

MEASUREMENTS Baseline serum creatinine, hemoglobin, and serum albumin levels; type and volume of contrast agents; and post-CT serum creatinine level.

RESULTS Overall, CIN occurred in 13 (2.5%) patients. Incidences of CIN were 0.0%, 2.9%, and 12.1% in patients with an estimated glomerular filtration rate of 45-59, 30-44, and <30 mL/min/1.73 m(2), respectively. The risk of CIN was increased in patients with severely decreased kidney function and diabetes. The development of CIN consequently increased the risk of renal replacement therapy (P < 0.001 by log-rank), and the risk was significantly accentuated in patients with estimated glomerular filtration rate <30 mL/min/1.73 m(2).

LIMITATIONS A single-center study and comparison with previous studies.

CONCLUSIONS The incidence of CIN was relatively low in patients treated with saline and NAC. The development of CIN predisposed to poor kidney survival in the long term.