Objective To examine the changing trend of plasma Neutrophil gelatinase-associated lipocalin (NGAL) after contrast exposure and to elucidate whether NGAL was good early biomarker for diagnosis of contrast induced acute kidney injury (CIAKI).

Method 231 patients undergoing percutaneous coronary intervention were enrolled. Blood samples were collected before and 2, 4, 8, 24, and 48 h after procedure. NGAL was measured with ELISA kit. CIAKI was defined as an increase in the serum creatinine values of ≥25% or ≥44.2 μmol/L. Receiver-operating characteristic (ROC) curves were generated and the area under the curve (AUC) calculated.

Results At baseline, the plasma NGAL (69.4±29.8 ng/ml) was correlated positively with creatinine (90.9±20.4 μmol/L) (r²=0.341, p<0.001) The plasma NGAL increased at 2 h and reached peak at 8 h and decreased at 24 h after procedures. Among all the patients, 29 patients (12.6%) developed CIAKI. The sensitivity, specificity, and ROC curve for prediction of CIN were excellent for the 2 h plasma NGAL (75%, 89%, and 0.90, respectively).

Conclusion NGAL seems to be a potential early biomarker for CIAKI.