RETAINED NEPHROSTOMY THREAD PROVIDING A NIDUS FOR ATYPICAL RENAL CALCIFICATION

Percutaneous nephrostomy (PCN) is a commonly performed procedure. The indications have expanded from merely providing emergency decompressio n of obstruction to being the initial step of many interventional proc edures including percutaneous nephrolithotomy, ureteral stenting dilat ion and biopsy. Nephrostomy tube design has evolved from a simple troc ar to the current self-retaining loop catheters. These catheters conta in a suture which, when secured, locks the loop of the catheter in ord er to prevent accidental removal of the catheter. We present a case wh ere incomplete removal of the locking suture providing the nidus for c alcification within the renal pelvis.