has_part has part has part characteristic of part of inheres in part of inheres in part of has modifier Renal necrosis Renal papillary necrosis Premature death of cells in the renal papilla (the apex of a renal pyramid which projects into the cavity of a calyx of the kidney and through which collecting ducts discharge urine). Histologically, one observes pale tissue with typical appearance of coagulative necrosis, affecting the renal papillae. Necrosis can be identified by pyknotic nuclei and simplified, flattened epithelium of proximal tubules. The tubular and glomerular basement membranes are still visible without viable nuclei. abnormal necrotic renal papilla