Bilateral extra hilar branching pattern of renal artery: Its embryological basis and clinical elucidation

Extra-hilar branching refers to the main renal artery dividing before reaching the hilum of the kidney into an anterior and posterior branch. Embryologically, initial segmentation of renal artery may occur due to ablation of renin cell precursors and mutations of the renin-angiotensin system or due to delayin communication between the constituents located within the mesenchyme of the vascular structures and those found in the mesenchyme of the metanephros, such as hepatocyte growth factor and glial-derived neurotrophic factor. The variations in renal vascular anatomy is of clinical relevance to surgeons and radiologists in cases of renal transplantation, vascular reconstruction and assessment of renovascular hypertension. The present case report involves the extra hilar branching of bilateral renal arteries with its embryological basis and clinical elucidation.