Purpose or Case Report: Acute kidney injury (AKI) remains a concern in hospitalized children undergoing computed tomography (CT) examinations with intravenous (IV) iodinated contrast material (ICM). Adult studies have shown frequencies of AKI after CT with IV ICM to be similar to propensity score-matched ICM unexposed cohorts. The purpose of this study is to evaluate the association between IV ICM exposure and AKI in hospitalized pediatric patients with stable kidney function undergoing computed tomography (CT).
Methods & Materials: This retrospective observational cohort study was institutional review board-approved and HIPAA-compliant; informed consent was waived. Hospitalized patients ≤18 years-old with stable kidney function and available pre- and post-imaging serum creatinine (SCr) who underwent CT with IV ICM or abdominal ultrasound (US) between January 2009 and November 2018 were identified. 1:1 propensity score matching was performed using 23 covariates, stratified by pre-imaging eGFR (estimated glomerular filtration rate; ≥/<60 mL/min/1.73m²). AKI was defined by Acute Kidney Injury Network SCr-related criteria. Multivariable logistic regression was performed to identify risk factors for post-imaging AKI, including the effects of pre-imaging eGFR and IV ICM exposure.
Results: 1,850 unique patients were included in the propensity score matched population (n=925 per cohort). Frequency of post-imaging AKI in patients with eGFR≥60 mL/min/1.73m² was 2.2% (20/889) for both CT and US (odds ratio [OR]=0.98; 95% confidence interval [CI]: 0.52,1.86; p=0.95), and in patients with eGFR<60 mL/min/1.73 m² was 5.6% (2/36) and 11.1% (4/36) in the CT and US cohorts, respectively (OR=0.75; 95% CI: 0.11,5.00; p=0.76). Significant predictors of AKI included pre-imaging eGFR (p=0.0011), body mass index (p=0.0025), acquired kidney disease (p=0.049), and nephrotoxic antibiotic exposure (p=0.0007); IV ICM exposure was not predictive.
Conclusions: Hospitalized children with stable kidney function who underwent CT with IV ICM had a similar frequency of AKI compared to a propensity score-matched ICM unexposed cohort. In the majority of pediatric inpatients undergoing contrast-enhanced CT (eGFR≥60 mL/min/1.73m²), ICM is not independently associated with AKI.