Renal papillary necrosis in a transplanted kidney

Abstract

Renal papillary necrosis (RPN) was first described in autopsy studies. The characteristic pathologic feature is selective coagulative necrosis of the inner medulla and papillae of the renal pyramids. This area of the renal parenchyma is vulnerable to ischaemic injury because its blood supply comes from narrow caliber vessels with low rates of blood flow. RPN represents the end-point of a number of conditions which compromise blood flow or increase metabolic demand in this vulnerable region. Diagnosis of RPN is typically made radiologically and operative management is not usually required.