Can Angiomyolipomas (AMLs) cause bleeding on more than one occasion?

Angiomyolipomas Can Cause Bleeding on Multiple Occasions

Yes, angiomyolipomas (AMLs) can cause bleeding on more than one occasion, with bleeding complications occurring mostly between ages 15-50 years, although the risk is present at any age. 1

Risk Factors for Recurrent Bleeding

• AMLs have a significant risk of spontaneous hemorrhage that can range from limited perirenal hematoma to life-threatening internal hemorrhage 1
• The lifetime risk of spontaneous hemorrhage from AMLs may exceed 20%, particularly for larger lesions 1
• After an initial bleeding episode, patients remain at risk for subsequent bleeding events, especially with:
  • Larger tumor size (>3 cm in diameter) 1
  • Presence of intralesional aneurysms (significantly more frequent in patients with hemorrhagic presentation) 2
  • Association with tuberous sclerosis complex (TSC) 1

Evidence of Recurrent Bleeding

• The natural history of AMLs includes the potential for multiple bleeding episodes over time 1
• Case reports document patients requiring multiple hospitalizations and transfusions for repeated bleeding episodes from AMLs 3
• One documented case showed a patient with bilateral AMLs who experienced 11 hospitalizations and required 44 transfusions over a 20-year period due to recurrent bleeding episodes 3
• The risk of bleeding is continuous and present throughout the patient's lifetime, requiring ongoing monitoring 1

Risk Assessment and Monitoring

• Strict kidney imaging follow-up is needed to monitor the risk of bleeding due to AML rupture 1
• Age correlates strongly with the frequency, number, and size of kidney lesions in patients with TSC 1
• The growth rate of AMLs is typically slow before adolescence, accelerates during adolescence and young adulthood, and then slows after age 40 1
• Pregnancy is associated with an increased risk of bleeding from AMLs 1

Management Implications

• After an initial bleeding episode, preventive treatment should be considered to reduce the risk of subsequent bleeding events 2
• Treatment options include:
  • Selective arterial embolization (SAE) for both emergency treatment of active bleeding and prophylactic management 2, 4
  • mTORC1 inhibition therapy for AMLs presenting substantial bleeding risk 1
  • Surgical intervention when necessary, with preference for nephron-sparing approaches 5
• For patients with TSC, a multidisciplinary approach is particularly important due to the higher risk of multiple and bilateral lesions 2

Special Considerations

• Patients should be warned about the risk of recurrent bleeding and instructed to seek urgent medical attention if symptoms of bleeding occur 1
• Pregnant women with AMLs should receive information about the increased risk of bleeding during pregnancy 1
• The presence of intralesional aneurysms should be considered in any prophylactic treatment decision, as they significantly increase bleeding risk 2