A Large Pelvic Haematoma Caused by a Local Anaesthetic Flexible Cystoscopy Injection of Intradetrusor Botulinum Toxin A: A Case Report

A 55-year-old female attended the Outpatient Urology Department for local anaesthetic flexible cystoscopy and intradetrusor botulinum toxin A injection. Having been diagnosed with urodynamics-proven low-grade detrusor overactivity in 2017, she was well-established on six-monthly Botox® injections. As part of her ongoing treatment, 100 units of Allergan Botox diluted with saline in a 10 mL syringe were injected via 20 punctures. There were no immediate complications. Three days later, she presented with abdominal pain and haemorrhagic discolouration around her umbilicus (Cullen's sign). Haemoglobin had dropped by 37 g/L, from 130 to 93 g/L. An urgent CT of the abdomen and pelvis with contrast revealed a large 10 x 4 cm pelvic haematoma, which was managed conservatively. A repeat CT of the abdomen and pelvis with contrast three weeks later showed no change in the pelvic haematoma size, but a reduction in attenuation suggested partial liquefaction.