Complications of sterile abscess formation and pulmonary embolism following periurethral bulking agents

Purpose: Agents currently used in the treatment of urinary incontinence sec ondary to intrinsic sphincter deficiency are effective and minimally invasi ve. Ensuring a lack of sensitivity to the product or use of autologous mate rial, such as fat, minimizes significant problems. However, local and syste mic complications can occur with any bulking agent. We describe rare compli cations of periurethral, bulk injections. Materials and Methods: Three cases of sterile abscess formation and I of pu lmonary embolism after periurethral bulk injections were reviewed. Two pati ents with intrinsic sphincter deficiency were treated with transurethral in jection of glutaraldehyde cross-linked collagen at the Mayo Clinic, 1 also treated with collagen for intrinsic sphincter deficiency was referred from elsewhere and I underwent periurethral injection of autologous fat for intr insic sphincter deficiency elsewhere. Clinical information and patient foll owup were obtained from medical records and discussion with treating physic ians. Results: Three patients treated with collagen presented with sterile absces ses at the injection site after routine transurethral injection. Documentat ion of the abscesses included cystoscopic findings, magnetic resonance imag ing of the pelvis and/or transvaginal ultrasound. Drainage procedures for r elief of obstructive and irritative voiding symptoms were required in 2 pat ients. In 1 of these patients transurethral unroofing failed, and transvagi nal incision and drainage were required while the other had slow spontaneou s improvement but a mass remained at the injection site 3 months later. Rep eat skin testing was negative in 2 of 3 cases. Currently, these 3 patients are asymptomatic except for continued urinary incontinence. Pulmonary embol ism was documented in I patient who underwent periurethral autologous fat i njection. This patient survived without long-term consequences but was main tained on ventilatory support for a short time. Conclusions: In general, periurethral injection of bulk agents is safe and effective. However, injectable bulk agents are not without risk of complica tions, some of which are life threatening and others of considerable morbid ity that may require operative intervention.