[Replacement of a dislodged nephrostomy catheter]

A common complication of percutaneous nephrostomy is accidental withdrawal of the catheter. Opacification of the nephrostomy tract demonstrates an intact passage to the collecting system. First one should try to negotiate the tract with a probe under fluoroscopy. If the pelvocalyceal system cannot be entered by probing alone, a puncture is done next. The Seldinger-needle together with a 22-gauge needle and a mandrin allows to combine probing, puncture and fluoroscopy of the nephrostomy tract.