Category: Other, Miscellaneous
VS15-3 - Allium ureteral stents: exit strategy in case of migration
Introduction & Objective :
Ureteral stenoses and fistulae are currently treated by complex surgery, not always possible because of patient-specific anatomical and clinical features. In these cases, palliative maneuvers, like DJ ureteral stents or nephrostomies, are often adopted, influencing negatively patient’s quality of life. Allium ureteral stents (AUSs) represent an interesting alternative. They are self-expanding large-caliber devices, made up of nitinol and totally covered by a polymeric material to prevent tissue ingrowth. They are designed to stay inside ureter for 1 to 3 years. AUSs may be removed endoscopically unraveling it into a thread-like strip.
Our aim was to present the exit strategy adopted by our center to remove AUSs in case of migration.
Methods :
We present two patients treated with 12cm-long and 30Fr-large AUSs. The first case deals with a 47-year-old man with iatrogenic left pelvic ureteral stenosis, previously treated with a DJ ureteral stent and a nephrostomy for 3 months. The second case deals with a 51-year-old woman, who presented a left lumbar ureteral stenosis, firstly treated with the placement of a DJ ureteral stent for 7 months.
Results :
In the first case, after 7 days we removed the AUS retrogradely because of device migration above the stenotic portion. The maneuver resulted particularly challenging and delicate, as the stent should pass through the stenotic ureteral tract.
In the second case, after AUS positioning, hydronephrosis persisted in the following months and the patient suffered from recurrent urinary tract infections, likely due to stent colonization. The CT scan showed the AUS migrated into the renal pelvis, demanding a percutaneous renal access to remove it. After two days, the patient complained about low back pain and we registered anemia: the CT scan showed a renal pseudoaneurysm that required embolization.
Conclusions :
The AUS offers a valid solution for ureteral fistulae and stenoses, especially in patients not eligible for major surgery. However, it is not free from complications; among them, the possibility of migration, needing device removal. A percutaneous renal access may be required exposing patients to further complications. Therefore, an adequate patient selection is mandatory, and the treatment should be managed by expert urologists.
Gianluca Sampogna
– Resident, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy
Stefano Paolo Zanetti
– Resident, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy
Andrea Gallioli
– Resident, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy
Elisa De Lorenzis
– Resident, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy- FP
Franco Palmisano
– Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy - MF
Matteo Fontana
– Resident, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy - IS
Ilaria Sabatini
– Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy - SL
Stefano Luzzago
– Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy 
Luca Boeri
– Resident, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milano, Lombardia, Italy- GA
Giancarlo Albo
– Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy 
Fabrizio Longo
– Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy
Emanuele Montanari
– Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico, Department of Clinical Sciences and Community Health, University of Milan, Urology, Milan, Italy, Milan, Lombardia, Italy