Infected retroperitoneal fat necrosis after laparoscopic partial nephrectomy

Fat necrosis (FN) is a common surgical complication after breast and plastic surgery procedures involving reconstruction and tissue flaps with an incidence reported ranging from 10 to 39%.1 Histologically, FN is described as a focus of lipid-laden macrophages and chronic inflammationwith a foreign body giant cell reaction.2 FN in breasts has a variable clinical presentation that can range from a tender mass with skin retraction to a palpable firmness, both of which can be concerning for malignancy. In the retroperitoneum, FN is classically associated with the sequela of acute pancreatitis. In the absence of pancreatitis, FN in the retroperitoneum is exceedingly rare.3e5 Herein we present a case of infected retroperitoneal FN after a laparoscopic partial nephrectomy in a patient with an ileal conduit (IC).