Massive Renal Intratubular Hemorrhage With Herniations into Renal Veins: Report of a Case.

A 30-year-old woman suffered intractable gross hematuria of renal origin, which required nephrectomy after failed conservative management. Pathological examination revealed massive intratubular hemorrhage and frequent deposition of an amorphous and homogenous material positive for Periodic Acid-Schiff (PAS) stain in the corticomedullary junction. This substance is frequently herniated into the lumen of thin-walled veins of arcuate size. There was no apparent cause for the bleeding. To the best of our knowledge this is the fourth reported case with these peculiar histopathological findings associated with hematuria. We discuss some hypotheses as to the etiopathogenesis of this rare and interesting condition.