[AN EXPERIENCE OF PARTIAL NEPHRECTOMY IN A PATIENT WITH VON WILLEBRAND DISEASE].

A 28-year-old male visited a nearby hospital with chief complaint of bilateral back pain and fever. He was diagnosed with a right complex renal cyst (Bosniak classification, IIF) with a kidney stone and was referred to our hospital. We first suspected an incarcerated kidney stone and performed flexible transurethral lithotomy; however, his symptoms did not improve. Blood examination revealed prolonged APTT; subsequently, he was diagnosed with von Willebrand disease (VWD). Because he experienced pain due to the hemorrhagic renal cyst, we performed partial nephrectomy. Preoperatively, we supplemented the von Willebrand factor (VWF) based on the VWF activity in the patient. Although intraoperative bleeding was well controlled, he developed bleeding from pseudoaneurysms on the postoperative day (POD) 6. We immediately performed transarterial embolization along with VWF replenishment. VWF supplementation was discontinued on POD 14, and the patient was discharged on POD 23. Since then, he has not experienced a bleeding recurrence or pain. In patients with VWD, the perioperative administration of desmopressin or VWF is recommended. Although several reports showed that surgeries involving these treatments are safe, only three cases with VWD, including the present case where the patient underwent partial nephrectomy, have been reported. In the present case, postoperative bleeding occurred despite exhibiting adequate perioperative VWF activity. Thus, bleeding complications in patients with VWD undergoing partial nephrectomy must be considered and should be carefully followed up.