LAUSR

Objective To report on the second case illustrating the possibility of developing renal arteriovenous malformation (AVM) following relatively safe flexible ureterorenoscopy (FURS) and holmium laser lithotripsy. The use of FURS and holmium laser lithotripsy for the treatment of large renal calculi is gaining in popularity and has been shown to be safer than percutaneous nephrolithotomy (PCNL). The formation of AVM, although rare, is well-documented following PCNL. However, reviewing the literature up to June 2018, revealed only one reported case of AVM following FURS and holmium laser lithotripsy. Methods In the current case report, a 79-year-old man with multiple comorbidities including hypertension, diabetes and Stage-4 chronic kidney disease who had previously undergone left-side extracorporeal shockwave lithotripsy and FURS with holmium laser lithotripsy presented with bilateral symptomatic large renal stones. He underwent simultaneous bilateral FURS and holmium laser lithotripsy and was discharged home the next day with almost clear urine. Results However, 4 days later, he presented with gross haematuria, which required continuous bladder irrigation and blood transfusion. Computed tomography showed a left subcapsular, perinephric and retroperitoneal haematoma. Angiography revealed pseudoaneurysm in two small branches of the left main renal artery with contrast extravasation. Both branches were selectively embolised using micro-coils and the haematuria ceased. Conclusion Although a relatively safe procedure, FURS and holmium laser lithotripsy can be associated with major complications such as intrarenal AVM. This can probably be prevented by judicious and careful use of laser energy in patients with large stone burdens and premorbid conditions.