Segmental renal autotransplantation in a patient with a single kidney affected by arteriovenous malformation and aneurysm.

A 24 year old man with severe renovascular hypertension was diagnosed as having an arteriovenous malformation of the left kidney with an aneurysm of the renal artery 12 years after right nephrectomy. Surgical reconstruction proved unsuccessful, but subsequent autotransplantation of the lower segment of the kidney 18 hours later saved the patient. He made an excellent recovery and is now normotensive and able to lead a normal life.

[The influence of the renin-angiotensin system on autoregulation of renal blood flow and intrarenal hemodynamics (author's transl)]. / Uber die Beziehungen zwischen Autoregulation des renalen Blutflusses, intrarenaler Hämodynamik und dem Renin-Angiotensin-System

The discussion of renal hemodynamics has to include three phenomena: the autoregulation of renal blood flow, the existence of different intrarenal perfusion compartments, and the intrarenal renin-angiotensin-system. The autoregulation of renal blood flow is characterized by the constancy of renal blood flow inspite of a wide range of renal perfusion pressure (70-220 mm Hg). This is due to the ability of the kidney to adjust vascular resistance to pressure changes. Renal perfusion is not homogenous but consists of different perfusion compartments which may be distinguished according to characteristic anatomy, function and innervation. Autoregulation of renal blood flow and distribution of intrarenal perfusion to different compartments are interdependent and are shown to be both under the control of an intrarenal "local" renin-angiotensin system.