Neutrophil Gelatinase-Associated Lipocalin (NGAL) as a Predictive Biomarker for Contrast Induced Nephropathy, in Moderate Risk Patients after Cardiac Catheterization

Background: Contrast-induced nephropathy (CIN) is an acute kidney insult (AKI) defined as creatinine (SCr) increase 48 to 72 h after intravenous contrast. Because most subjects undergoing invasive cardiac procedures are discharged within 24 h, SCr is unsuitable for CIN detection. This study compares between serum NGAL, and SCr in moderate risk patients after coronary angiography with/without intervention for the occurrence of CIN. Methods: This was a prospective provisional study carried out from January 2015 to July 2016, in the department of Cardiology, El-Minia University Hospital (EGYPT). 42 moderate risk Subjects (Mehran Score 6 to 10 with estimated 14% risk of developing CIN) undergoing elective coronary angiography with/without intervention were enrolled. Serum NGAL was assessed before and 4 h post-procedure. SCr was measured before and 48 h postprocedure. CIN was defined as SCr increase >25% or >0.5 mg/dL from baseline after coronary angiography within 48 h, without explanation or the presence of any cause. Results: 30 males and 12 females with mean age 54.92 ± 10.14 (36-73) years and mean baseline SCr 1.01 ± 0.25 mg/dl (0.6-1.8) were enrolled. A contrast volume with mean 161.9 ± 76.35 mL (100-300) was administered. CIN was found in twelve subjects (28.6%). Included subjects were classified into those with and without CIN, NGAL was significantly elevated in subjects with CIN versus those without 4 h after coronary intervention 172.69 ± 70.48 (50-280 ng/mL) vs. 104.19 ± 53.03 (75-350 ng/mL) (P<0.001). Using a cutoff value of >174 ng/mL, 4-h NGAL was excellent predictor of CIN with 91.67% sensitivity, 93.33% specificity, 84.6% PPV, 96.6% NPV, 92.86% Accuracy and 92.86 area under (ROC) curve. Baseline demographics show no difference between those with and without CIN among study groups. Serum NGAL at 4 h post procedure (P<0.001) used as a predictor of the occurrence of CIN among study groups. Conclusions: Serum NGAL measured 4 h following coronary angiography with/without intervention after intravenous contrast administration can be used as a novel and helpful biomarker for the occurrence of CIN in moderate risk patient. The percentage of CIN incidence (28.6%) in this study in moderate risk patients highlight the useful use of serum NGAL 4 h post procedure measurement to predict, intervene and may prevent CIN.