Comparison of Neutrophil Gelatinase Associated Lipocalin with Serum Creatinine for Early Detection of Decrease in Estimated Glomerular Filtration Rate

Abstract

Objective: To determine the accuracy of Neutrophil Gelatinase Associated Lipocalin (NGAL) at 2 h compared to serum creatinine at 48 h after Computerized Tomography (CT) scan with contrast medium for early detection of decrease in estimated Glomerular Filtration Rate (eGFR). Materials and Methods:This Cross Sectional Study was carried out in Departments of Chemical Pathology and Radiology PNS SHIFA Karachi from 1stFebruary 2014 to 31st Jan 2015. One hundred and ten patients undergoing CT scan with contrastwere included. Serum creatinine wasmeasured byJaffé assay using Alkaline Picrate reagent on Modular P800 (Roche) analyzer before and 48 h after CT scan. eGFR was calculated by Modification of Diet in Renal Disease (MDRD) formula. Patients were divided into AKI and non-AKI groups. NGAL was analyzed by NGAL Reagent Kit on Triage meter pro at 2 h after contrast. Results: Out of 110 patients, 5 (4.54%) developed Acute Kidney Injury (AKI) 2 h after CT scan with contrast in which eGFR was decreased more than 25%. NGAL level in AKI group was 161ng/ml (IQR: 98 to 196) at 2 h after CT contrast was significantly higher than non-AKI group of 63ng/ml (IQR: 42 to 75). Serum creatinine showed significant rise but with delay of 24 – 48h after CT contrast in AKI group. There was a positive correlation between 2 h plasma NGAL and eGFR at 48 h, which was statistically significant. Conclusion: NGAL is a potential marker for early detection of decrease in eGFR and predictor of AKI.