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

Polyacrylamide hydrogel bulking agent (Bulkamid® [Axonics, Irvine, California, USA]) injection is used as a minimally invasive treatment for stress and mixed urinary incontinence in females. Several studies have demonstrated the short- and medium-term efficacy and safety of Bulkamid. However, there are limited data available on the long-term safety of this procedure. The authors report an unexpected and late complication associated with Bulkamid periurethral injection. An 80-year-old female, who had undergone Bulkamid periurethral injection for stress urinary incontinence 10 years previously, was referred to the authors’ clinic with recurrent lower urinary tract symptoms and dysuria. Investigations with ultrasound and cystoscopy confirmed a single 2 cm bladder stone adhered to an exposed Bulkamid agent at its injection site. Exposed intravesical Bulkamid can act as a foreign body with lithogenic potential to cause urinary bladder stone formation. This article highlights urinary bladder stone formation as a late potential complication of Bulkamid periurethral injection.