Retained Ureteral Stent Encrustation After Stent Removal: A Case Report.

Ureteral stents are used to relieve acute or chronic urinary tract obstructions and may be complicated by stent encrustation. The development of encrustation is related to indwelling time, stent composition, bacterial biofilm formation, malabsorptive disorders, metabolic disorders (hypercalcemia, hyperuricosuria, pH imbalance), and cancer. Without intervention, encrustation may lead to luminal obstruction, infection, stent fracture, or ureteral avulsion during removal. Rarely, forced removal of an encrusted stent may cause the encrustation to remain in the urinary tract which can lead to further complications. Diagnosis of a retained encrustation includes evaluation with X-ray, ultrasound, and CT. Management strategies of retained encrustations are not standardized but may include removal with flexible ureteroscopy. In the following case, we present a 58-year-old male with retained encrustation material following non-forced stent removal that was not readily observed on initial imaging. CT demonstrated a curved, tubular radiodensity representing calcified encrustation material, and the diagnosis of retained encrustation was confirmed after successful removal with flexible ureteroscopy. We concluded that ureteral stent encrustation can remain in the urinary collecting system following stent removal, although this complication is rare and not well studied.