Abstract
During this era of advanced and minimally invasive procedures for treating urolithiasis, percutaneous nephrolithotomy (PCNL) remains the primary choice for removing large renal calculi. While there are various known complications associated with PCNL, such as bleeding, sepsis and injury to neighboring organs, the occurrence of retained foreign bodies as a result of the procedure is rarely reported. In this case report, we present a unique instance of encrustation involving a retained guidewire sheath following PCNL, which was initially mistaken for a residual stone fragment in imaging studies. Fortunately, the foreign body was successfully removed using retrograde intrarenal surgery.