Abstract 3281: NGAL is an Early Predictive Biomarker of Acute Kidney Injury Following Cardiac Catheterization with Contrast Administration in Children
Introduction: Acute kidney injury (AKI) occurs in about 10% of pts who receive contrast agents. However, diagnosis using serum creatinine may be delayed several days. We hypothesized that neutrophil gelatinase-associated lipocalin (NGAL), produced in tubule cells in response to injury, is a predictive biomarker of AKI after contrast administration.
Methods: We prospectively enrolled 91 children (mean age 84mo, range 0–216) with congenital heart disease who were undergoing elective cardiac catheterization with contrast administration (CC). Serial urine and serum samples, obtained at baseline and at multiple time points after CC were analyzed in a double blind fashion by ELISA for NGAL expression. AKI, defined as a 50% increase in serum creatinine from baseline, was the primary end-point.
Results: AKI was found in 11 pts (12%), but diagnosis using serum creatinine was only possible 12–24 hours after CC. In contrast, significant elevation of urine and serum concentration of NGAL was noted early after CC in those 11 pts. Urine and serum concentration of NGAL did not vary from baseline in the remaining pts without AKI (Table⇓). With a cut-off value of 100ng/ml, the 6 hour urine NGAL revealed the highest sensitivity and specificity (85% and 98% respectively) in predicting AKI. The biomarker properties were comparably excellent for both the 2 and 6 hour serum NGAL measurements (82% sensitivity; 100% specificity). By multivariate analysis, NGAL concentrations in the urine (R2=0.52, p<0.0001) and serum (R2=0.4, p<0.0001) at the 2 hour time point were found to be powerful independent predictors of AKI. Pt demographics and contrast volume were not predictive of AKI.
Conclusion: Elevation of NGAL concentration in urine and serum are early predictors of AKI following cardiac catheterization and contrast administration. Using this biomarker of renal dysfunction, earlier therapeutic intervention may be possible, particularly in those pts at higher risk for renal insufficiency.