Unilateral papillary necrosis complicating renal artery stenosis--evidence of activation of the intrarenal renin-angiotensin system?

We report an association between renal artery stenosis and papillary necrosis. We studied three kidneys with renal artery stenosis, two of which showed ipsilateral acute papillary necrosis. In all three cases there had been a sudden fall in perfusion of the ischaemic kidney. In the case with intact papillae, immunostainable renin was normal in amount and distribution, whereas both kidneys with papillary necrosis showed hyperplasia of renin-containing cells, and these were mainly in the JGAs of the juxtamedullary cortex. Since the contralateral kidneys were spared, we suggest that in an ischaemic kidney with hyperplasia of renin-secreting cells in the deep cortex, local activation of the renin-angiotensin system could cause acute papillary necrosis due to vasoconstriction.