<prompt> Renal aery stenosis may occur in all of the following except:AtherosclerosisFibromuscular dysplasiaTakayasus aeritisTakayasus aeritis  <response>: Answer is D Polyaeritis nodosa: Amongst the options provided renal aery stenosis is least likely to he seen in association with Polyaeritis nodosa. Atherosclerosis and Fibromuscular disease - Renal aery stenosis is produced predominantly by atherosclerotic occlusive disease 80 to 90 of patients or fibromuscular dysplasia 10-15 of patients.- CMDT06 p 460 - The common cause of renal aery stenosis in the middle aged and elderly is an atheromatous plaque at origin of renal aery. Harrison In younger women stenosis is due to intrinsic structural abnormalities of the aerial wall caused by a heterogenous group of lesions called fibromuscular dysplasia. - Harrison 16th1707 PAN or Takayasu aeritis ? Harrison, CMDT do not mention PAN or Takayasu aeritis as a cause for renal aery stenosis. However, Takayasu aeritis is ceainly a more common cause of renal aery stenosis than PAN. Takayasu aeritis Aoo-aeritis is beleiveds to he the most common of renovascular hypeension in India and China. -- Diseases of Kidney and Urinary Tract 81171279 