Neutrophil gelatinase-associated lipocalin as a diagnostic marker of acute kidney injury in pre-eclampsia

AimNeutrophil gelatinase-associated lipocalin (NGAL) is an emerging biomarker for early diagnosis of acute kidney injury (AKI). This study investigated the use of urinary NGAL as a marker of AKI in women with pre-eclampsia. MethodsUrine and serum samples were collected over 24 h from 78 healthy and 109 pre-eclamptic women, with baseline samples taken at admission to the maternity unit; NGAL was assayed in serial urine samples. ResultsBaseline neutrophil gelatinase-associated lipocalin did not differ significantly between women who were healthy, those with pre-eclampsia, or with AKI (P = 0.55 for trend). When the pre-eclamptic group was divided into those with eclampsia (median, 60.5 ng/mL; IQR, 23.4-173 ng/mL; n = 19), uncomplicated pre-eclampsia (median, 18.8 ng/mL; IQR, 7.5-52.8 ng/mL; n = 48; P < 0.05 vs eclampsia), imminent eclampsia (median, 30.7 ng/mL; IQR, 13.9-49.3 ng/mL; n = 22) and pre-eclampsia with acute kidney injury (median, 60.3 ng/mL; IQR, 23.5-159 ng/mL, n = 14), however, NGAL level did differ. On multivariate regression analysis, the only significant correlate of NGAL level was the presence of eclampsia (beta = 0.22, P < 0.05). On receiver operating characteristic curve analysis, baseline NGAL did not discriminate between subjects with or without AKI (area under the curve, 0.61; 95%CI: 0.43-0.78; P = 0.12). ConclusionNeutrophil gelatinase-associated lipocalin level at baseline and over a 24-h period does not provide a suitable diagnostic test for AKI in pre-eclamptic subjects.