Microangiography of end-stage kidneys in relation to high renin hypertension.

Microangiography of end-stage kidneys in relation to high renin hypertension. 15 patients with end-stage renal disease (ESRD) and maintained on chronic hemodialysis were studied with respect to hypertension, the plasma renin activity (PRA) and microangiography of endstage kidneys which were removed for various reasons. The microangiographic patterns were classified into three according to characteristic findings: The first one was characterized by gross dilatation of interlobular arteries and afferent arterioles with poor opacification of efferent and peritubular vessels. This pattern was designated as type 1 (Fig. 1, 2.) Another pattern had total irregularity of renal vascular architectures and differentiation of cortical arteries were impossible. This was classified as type 2 (Fig. 3, 4.) The third one which was grouped as type 3 was characterized by good and fine vascularity of cortical vessels without evidence of obstruction (Fig. 5, 6.) These findings were confirmed by histological studies. All 5 patients with uncontrollable hypertension had type 3 kidneys. Their PRA were abnormally high, but normalized after bilateral nephrectomy. It was suggested that intractable hypertension in patients with ESRD may be an evidence of relatively well preserved cortical circulation despite of extensive parenchymal destruction as seen in type 3 kidneys, in which intensive hemodialysis and ultrafiltration will result in volume depletion, decrease in renal perfusion pressure and excessive renin secretion from the remaining nephrons.