Use of Polyacrylamide Hydrogel for Vesicoureteral Reflux Treatment, a Review

Abstract

Purpose of the review: Vesicoureteral reflux (VUR) is a common pathology encountered in pediatric urology. If left untreated, this condition can lead to infectious complications, hypertension and loss of renal function by scars. There is a trend for minimally invasive procedures to minimise treatment-related complications. Endoscopic subureteral injection of bulking agent in the treatment of VUR is an example of minimally invasive options. Several bulking agents have been studied and the perfect agent has not yet been discovered. Polyacrylamide hydrogel is a relatively new agent used to treat VUR and its use will be reviewed. Recent findings: Three modern studies from a Canadian group have evaluated the use of polyacrylamide hydrogel for endoscopic injection to treat VUR. The first study reported a cure rate of 81.2% without major complication. In the second study, injection of polyacrylamide hydrogel was compared to dextranomer hyaluronic acid and no significant difference was observed, with overall success rate of 73.1% and 77.5% respectively. The third trial evaluated the long-term efficacy and safety of polyacrylamide hydrogel with a 36-month follow-up. Overall success at 3 months was 70.7% and no patient had de novo hydronephrosis or calcification of the agent at 36 months. Conclusion: Polyacrylamide hydrogel seems to be a safe and effective alternative bulking agent in the treatment of VUR. The contribution from other centers to validate those data would be valuable.

Urinary Bladder Stone: A Late Complication of Bulkamid® Periurethral Bulking Injection

“…This is seen regularly with retained iatrogenic and non-iatrogenic objects, including ureteric stents, long-term urinary catheters, retained suturing materials, and inserted domestic items. 8 While Bulkamid has demonstrated long-term resistance to calcification within soft tissue in a previous study, 6 there are no experimental reports with long-term exposure of Bulkamid to urine. Bulkamid exposure to the intravesical urine long-term may have the potential to accumulate minerals from urine over time, thus allowing for layered stone formation.…”

“…Its suitability for in vivo soft tissue injection is owed to its non-biodegradability, non-toxicity, and resistance to migration and calcification long-term. 6 Article Despite its safety profile, Bulkamid injection for stress urinary incontinence has some reported adverse effects. The most frequently reported adverse effects were pain at the injection site and urinary tract infections.…”

A comprehensive review on hydrogel materials in urology: Problems, methods, and new opportunities

“…The dextranomer microspheres placed in the hydrogel stimulate the ingrowth of collagen and the production of connective tissue. However, the application of hyaluronic acid generates the risk of a decrease in the volume of the element over time, which shortens the therapeutic effect of the material and causes a need for subsequent applications 106–109 …”

“…The composition is a biocompatible, non‐toxic hydrogel that is non‐biodegradable under physiological conditions, ensuring the implant volume's stability during the complete therapeutic process. In addition, it is characterized by high viscoelasticity and does not contain small particles in its structure, thus eliminating the risk of calcification occurrence and migration 107,113,114 . Bulkamid® also allows for the ingrowth and proliferation of blood vessels from the periurethral tissue.…”

“…In addition, it is characterized by high viscoelasticity and does not contain small particles in its structure, thus eliminating the risk of calcification occurrence and migration. 107,113,114 Bulkamid ® also allows for the ingrowth and proliferation of blood vessels from the periurethral tissue. Its undoubted advantage is the possibility of implant imaging by ultra-sonographic methods.…”