Role Of Intrarenal Resistance Indices In The Renal Interlobular Arteries Measured By Doppler Ultrasound In Pre-Eclampsia

Abstract

Pre-eclampsia is a complication of pregnancy that mainly presents as new onset hypertension and often proteinuria in the mother. Feared as one of the most dreaded complications of pregnancy, pre-eclampsia can progress to multi-organ dysfunction, including cerebral, hepatic, and renal disease. There are different explanations for the development of pre-eclampsia, which are impaired pseudo-vasculogenesis, generalized endothelial dysfunction, increased concentration of antagonists of the vascular growth factor, circulating autoantibodies and the renin-angiotensin-aldosterone system(RAAS), disorders in the relaxin-gelatinase pathway. Ultrasonography (US) facilitates the acquisition of real-time qualitative and quantitative information regarding renal vasculature. The present prospective observational (case-control) study was conducted in the Department of Radio-diagnosis and Imaging, over a period of one and a half years to evaluate the role of maternal renal interlobular Doppler ultrasound in preeclampsia and to correlate the arterial resistive indices of umbilical and uterine arteries with maternal intrarenal resistance indices in pre-eclampsia. One hundred and twenty-six women with period of gestation more than 28 weeks diagnosed as pre-eclampsia were taken as cases and 126 pregnant women with no history of disease (present and past) were taken as controls. Renal interlobular arterial Doppler parameters (EDV, PI, RI) were significantly higher in pre-eclamptic women than in healthy pregnant women. Renal Doppler indices showed a positive correlation with proteinuria and systolic blood pressure in pre-eclamptic women. Combined intrarenal Doppler parameters (IRIs) showed a high diagnostic accuracy (88.29%) for predicting pre-eclampsia. On combination of the Doppler parameters namely IRIs and RI of the umbilical and uterine arteries, the specificity and positive predictive value for predicting pre-eclampsia rises to 100% each. There exists a significant difference between the intrarenal resistance indices in healthy and pre-eclamptic women. There exists a statistically significant correlation between intrarenal resistance indices and resistance indices of umbilical and uterine arteries in women with pre-eclampsia.