Renal pseudoaneurysm: an overview.

Renal pseudoaneurysm is a rare vascular lesion that arises when an arterial injury within the kidney leads to contained hemorrhage. The associated hematoma forms outside the arterial wall and is typically surrounded by a layer of fibrous inflammatory tissue and blood clot. These lesions are unstable and their rupture can lead to life-threatening hemorrhage. Renal pseudoaneurysm has been reported to occur in various clinical scenarios, including after renal trauma, surgery and percutaneous procedures, as well as inflammatory and neoplastic processes within the kidney. Endovascular selective angioembolization is the mainstay of treatment, although surgery might be indicated when hemostasis and repair of the arterial wall defect are required. Percutaneous ultrasound-guided embolization is an additional option for patients with unfavorable vascular anatomy, or who cannot tolerate or have contraindications to the use of intravenous contrast agents. Some evidence suggests that these lesions can regress without intervention, although observation alone is not recommended as a management strategy in the vast majority of patients owing to the high risk of rupture. Evaluation and management of patients with renal pseudoaneurysm must take into account each individual's circumstances, due to the difficulty of accurately predicting the probability of spontaneous resolution or rupture.