Non-invasive exchange of encrusted nephrostomy tubes using a modified sheath technique: technical description and case series

Percutaneous nephrostomy (PCN) catheter exchange is commonly performed using standard over-the-wire techniques; however, exchange may be challenging or unsuccessful in the setting of catheter encrustation. Failure of nephrostomy exchange may necessitate de novo renal access, increasing procedural risk and resource utilization. We describe a modified sheath technique to facilitate catheter exchange in difficult cases. All cases of nephrostomy tube exchange performed using a modified sheath technique between February 2025 and January 2026 at a single tertiary centre were retrospectively reviewed. Patients with encrusted nephrostomy tubes in whom conventional wire-guided exchange failed were included. Procedural technique, demographic data, technical success, and complications were evaluated. Technical success was achieved in 19 of 20 cases (95%) of encrusted nephrostomy tubes using the modified sheath technique. In one case, loss of tract access occurred due to sheath buckling, and the procedure was abandoned. No major procedure-related complications were observed. Nephrostomy tube exchange using a modified sheath technique demonstrates a high technical success rate in cases of challenging encrusted nephrostomy tubes. This fluoroscopy-guided approach preserves collecting system access and may serve as a practical minimally invasive salvage option in routine interventional radiology practice.