Renal papillary necrosis

Abstract

Renal papillary necrosis is not a pathologic entity but rather a descriptive term for a condition-necrosis of the renal papillae-that has various possible causes. The basic lesion in renal papillary necrosis originates from impairment of the vascular supply and from subsequent focal or diffuse ischemic necrosis of the distal segments of the renal pyramids. If the ischemic process in the medullary region is caused by a temporary spasm and normal circulation is restored within a reasonable period, or if predisposing conditions are corrected within a reasonable period, the involved tissues may recover. However, if ischemia continues and perfusion is not restored, irreversible coagulation necrosis, tubular fibrosis, and lobar infarcts result.