Combination of NGAL and Cystatin C for Prediction of Preeclampsia at 10-14 Weeks of Gestation.

BACKGROUND: Preeclampsia (PE) is a severe pregnancy complication and is an important cause for maternal and child death, premature delivery, and limited intrauterine growth and development. The aim of this study was to investigate the role of NGAL and cystatin C, alone and in combination, for early prediction of PE at 10 - 14 weeks of gestation. METHODS: Serum levels of NGAL and cystatin C were assessed in women at 10 - 14 weeks of gestation who subsequently developed PE (n = 128) and normal pregnancy outcome (n = 183). Comparison of clinical characteristics, NGAL, and cystatin C levels between normal pregnancy and PE groups were analyzed using Mann-Whitney test. The receiver operating characteristic curve (ROC curve) was used to analyze the value of serum NGAL and cystatin C levels in predicting PE. RESULTS: The levels of cystatin C and NGAL in the serum were significantly higher in the PE group [0.64 mg/L (0.52 - 0.78)] and [34.9 ng/mL (24.4 - 55.2), respectively] than in the normal pregnancy group [0.56 mg/L (0.49 - 0.65)] and [20.2 ng/mL (13.8 - 26.9), respectively]. ROC curve analysis showed that serum NGAL levels predicted the area under the curve in the PE period 0.739 (95% CI: 0.618 to 0.860). Serum cystatin C levels predicted the area under the curve in the PE period 0.722 (95% CI: 0.592 to 0.853). The combination of serum NGAL and cystatin C levels predicted the area under the curve in the PE period 0.877 (95% CI: 0.811 to 0.943). CONCLUSIONS: NGAL and cystatin C levels in serum appear to be ideal biomarkers for PE prediction at 10 - 14 weeks. The combination of NGAL and cystatin C will also be more valuable in discriminating patients at risk of developing PE from other pregnancy complications early in gestation.