The renal response to preeclampsia.

Proteinuria and decreased renal function are classic hallmarks of preeclampsia. The kidney, with its reliance on glomerular blood flow and glomerular barrier integrity, provides a unique window to view the preeclamptic disease process. This review briefly details the characteristic renal structural changes seen in preeclampsia and then focuses on the disordered renal hemodynamics and other determinants of ultrafiltration. Both renal blood flow and glomerular filtration rate (GFR) decrease in preeclampsia, although absolute values may remain above the nonpregnant range. A decrease in the ultrafiltration coefficient (K f ), in the order of 50%, either alone or in combination with reduced renal blood flow, is presented as the most likely mechanism for the decrease in GFR. Proteinuria develops, at least in part, secondary to impaired glomerular barrier integrity with a loss of size selectivity revealed by fractional dextran clearance studies and it is proposed, although yet to be proven, that this is accompanied by a loss of glomerular barrier charge selectivity.