Abstract: Objective To explore the value of cystatin C （Cys-C） and neutrophil gelatinase-associated apolipoprotein （NGAL） in early diagnosis of acute kidney injury （AKI） in patients with gestational hypertension. Methods Patients diagnosed with gestational hypertension in a hospital in Zigong City were recruited from 2015 to 2018 as 20 to 24 gestational weeks. At the time of diagnosis of gestational hypertension or first treatment for it in the hospital, after 4 weeks, 8 weeks, and within one week before delivery 5 ml of fasting venous blood was collected for Cys-C, Serum creatinine （SCr）, and NGAL detection. Patients with AKI and pregnancy-induced hypertension were selected as the case group, and patients with normal renal function and pregnancy-induced hypertension were the control group. The levels of Cys-C, SCr, and NGAL were compared between the two groups at different times, and the correlations between Cys-C and SCr, and NGAL and SCr were analyzed separately. Results A total of 488 patients with gestational hypertension were studied. The average age was （36. 2 ± 3. 8） years. The average BMI before pregnancy was （22. 45 ± 2. 26）. Of the participants, 44 （9. 0%） had abnormal childbearing history. At the end of pregnancy, AKI occurred in 39 patients （case group）, with an incidence rate of 8. 0%. There were statistically significant differences in the levels of SCr, Cys-C and NGAL in the case group at the time when gestational hypertension was diagnosed, 4 weeks of gestational hypertension, 8 weeks of gestational hypertension, and 1 week before giving birth （P<0. 01 for all）. At 4 weeks of pregnancy-induced hypertension and the end of pregnancy, the differences in Cys-C and NGAL levels between the case and control groups were statistically significant （P<0. 05 or P<0. 01）, and at 8 weeks of gestational hypertension and the end of pregnancy, the differences in SCr level between the case and control groups were statistically significant （P<0. 05 or P<0. 01）. In the case group, Cys-C level was positively correlated with SCr level at the time of diagnosis of gestational hypertension, 4 weeks of gestational hypertension, 8 weeks of gestational hypertension, and 1 week before the end of pregnancy （r=0. 075, 0. 145, 0. 256, 0. 365）, NGAL level was positively correlated with SCr level（r=0. 058, 0. 152, 0. 297, 0. 349）, and the correlation coefficient increased significantly with the development of AKI. Conclusion The detection of blood Cys-C and NGAL levels is highly sensitive to pregnancy-induced hypertension combined with AKI. The blood Cys-C and NGAL levels of can be used as routine testing items for the early diagnosis of AKI in this population.

Key words: Gestational hypertension, Acute kidney injury, Cystatin C, Serum creatinine, Neutrophil gelatinase-related apolipoprotein