Urology Journal

Abstract

Renal pelvis epidermoid cysts are extremely rare and are often misdiagnosed as stones or tumors. Only one previous case has been treated using the percutaneous approach. A 67-year-old female with diabetes who was receiving empagliflozin presented with imaging findings suggestive of a staghorn calculus. During percutaneous nephrolithotomy, whitish keratinous material was found in the renal pelvis, along with a small obstructing stone. All material was evacuated through the Amplatz sheath. Urine culture was negative. Histopathological examination confirmed an epidermoid cyst. A postoperative computed tomography scan at 1 month showed complete resolution. Epidermoid cysts can radiologically mimic staghorn calculi. A fungal ball was initially suspected because of diabetes and sodium-glucose cotransporter 2 inhibitor therapy, but radiopacity, negative culture, and histopathological findings ruled this out. Percutaneous nephrolithotomy served as both a diagnostic and therapeutic procedure while preserving renal function. Renal pelvis epidermoid cysts should be considered in the differential diagnosis of opaque pelvic lesions. Percutaneous nephrolithotomy is a minimally invasive, kidney-preserving treatment that can be performed as a renal-sparing procedure.