Diagnostic Value of Serum Cystatin-C and Uric Acid in Predicting Renal Impairment in Pre-Eclampsia

Abstract

Background: Preeclampsia, a significant contributor to maternal and fetal health risks, is characterized by hypertension and proteinuria occurring post 20 weeks of gestation. Timely identification of renal issues in pre-eclamptic individuals is essential to prevent severe complications. This study aimed to assess how serum cystatin-C and uric acid levels together could predict renal impairment in pre-eclamptic patients. Methods: This longitudinal study was conducted from June 2023 to May 2024 at the Department of Physiology, LUMHS, in collaboration with the gynecology and obstetrics units of Civil Hospital, Hyderabad, and Liaquat University Hospital, Jamshoro. A total of 150 pre-eclamptic patients between 20 and 36 weeks of gestation were selected consecutively. Blood samples were collected at two stages; during 20-25 weeks and again at 36 weeks to measure serum cystatin-C and uric acid levels. Statistical analysis was performed using SPSS version 26.0, with descriptive statistics summarizing patient characteristics, chi-square tests, ANOVA, Spearman correlation, and ROC curve were used to analyze biomarker levels and their relationship with gestational age. Results: The study demonstrated significantly elevated serum cystatin-C (1.5 ± 0.3 mg/L) and uric acid levels (7.2 ± 1.5 mg/dL) in pre-eclamptic patients with renal impairment compared to those without (p < 0.01). A significant positive correlation was observed between gestational age and biomarker levels (r = 0.65, p < 0.01). The combined use of these biomarkers improved sensitivity to 90% and specificity to 85% in predicting renal impairment. Conclusion: Simultaneous measurement of serum cystatin-C and uric acid enhances early detection of renal impairment in pre-eclamptic patients.