Spontaneous Fatal Rupture of a Large Pseudoaneurysm within a Renal Angiomyolipoma following Incomplete Embolization in a Patient with Bilateral Renal Angiomyolipomas

Angiomyolipoma (AML)—a frequently seen solid renal tumor—is the most common benign tumor of the kidney. It was considered to be hamartomatous in origin and is now considered to be a member of the family of perivascular epithelioid cell (PEComa).[1] Classically thought to be associated with tuberous sclerosis that is an autosomal dominant disease with TSC1 or TSC2 gene mutation, around 80% AMLs may present sporadically.[1] They are also seen in patients with lymphangiomyomatosis and included in its diagnostic criteria.[2] Clinically, the tumor has myriad of presentations ranging from being completely asymptomatic at the time of diagnosis to abdominal pain, hematuria, recurrent urinary tract infection, and intratumoral bleed that can be occasionally massive requiring urgent embolization or nephrectomy.[3] On ultrasound AMLs appear as markedly hyperechoic to hypoechoic depending on the fat content. Though they are more frequently echogenic compared with renal cell carcinoma, overlap in imaging features can occur.[4] On color Doppler, pseudoaneurysms are seen as anechoic structure showing internal turbulent to-and-fro motion.[5] On computed tomographic (CT) scan, the diagnosis of renal AML depends on the detection of intralesional fat.[6]

• References

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