RESUMO
A renal angiomyolipoma (AML) is a rare, usually benign tumor consisting of smooth muscle cells, abnormal blood vessels, and fat tissue. Although AMLs are often asymptomatic, they can present with flank pain, hematuria, and a palpable mass in the abdomen. A significant complication involves rupture and hemorrhage into the retroperitoneal cavity, which can be life-threatening. The treatment approach has evolved from surgical removal to more conservative management, such as nephron-sparing embolization and mammalian target of rapamycin (mTOR) inhibitors for tuberous sclerosis complex (TSC)-associated AML. In March 2024, a 36-year-old female patient diagnosed with TSC was admitted to our department and underwent several endovascular embolizations after a life-threatening hemorrhage from a ruptured multilocular AML. The treatment was successful, with complete exclusion of the AMLs from circulation and without any complications during the postoperative period. This case emphasizes the effectiveness of selective arterial embolization using the Onyx liquid embolic system in managing AMLs and highlights the importance of preserving renal function. Methods used in AML diagnosis include ultrasound and computed tomography scans, with magnetic resonance imaging and biopsy recommended in difficult cases. Treatment depends on aspects such as tumor size, symptoms, and patient's general condition, with options ranging from active surveillance for small, asymptomatic AMLs to more invasive procedures for larger, symptomatic tumors. The main goal is to minimize symptoms and preserve renal function.
RESUMO
Renal arteriovenous anomalies are uncommon. They are characterized by an abnormal vascular connection that usually bypasses the capillary bed. Most are acquired arteriovenous fistulas (AVF) while the rest are congenital or idiopathic arteriovenous malformations (AVM). AVF are usually caused by renal interventions, trauma, or neoplastic processes. They can lead to hypertension, heart failure, hematuria, and renal insufficiency. A 69-year-old woman presented with arrhythmia, tachycardia, mild ankle edema, and increasing fatigue. Right kidney color Doppler ultrasound confirmed the presence of a huge AVM with a blood flow of 9 L/minute and a dilated, 35 mm in diameter, right renal vein. Two months later, an attempt to embolize the AVM failed as the Amplatzer™ Vascular Plug II (Abbott Laboratories, Chicago, Illinois, United States) migrated to the pulmonary circulation and was later removed. Complete embolization was achieved by implanting two Amplatzer Vascular Plug IIs, various embolization coils, histoacryl glue, and lipiodol. Control angiography revealed significant stenosis in the right subclavian artery endovascular access, which was managed with BeGraft (Bentley InnoMed GmbH, Hechingen, Germany) and Zilver (Cook Group Incorporated, Bloomington, Indiana, United States) stents. The patient was discharged on the third postoperative day, all her symptoms resolved, and she reported eventual recovery. Three months later, the patient was operated on due to a 40x58 mm pseudoaneurysm at the right femoral access site. Thus, renal AVMs should be included as a potential alternative diagnosis for various symptoms such as hematuria and hypertension resistant to medication. Endovascular embolization is a less-invasive, safer, and more effective option than open surgery but has a risk of complications. Success requires fully occluding the shunted vessel, preventing embolic material migration, and preserving normal arterial branches. It depends on selecting adequate techniques and embolic materials individually, based on etiology and precise vascular anatomy assessment.