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DOI: 10.1055/s-0038-1666963
Spontaneous Fatal Rupture of a Large Pseudoaneurysm within a Renal Angiomyolipoma following Incomplete Embolization in a Patient with Bilateral Renal Angiomyolipomas
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Publication History
Received: 13 February 2018
Accepted: 01 May 2018
Publication Date:
03 July 2018 (online)
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]
Case Presentation
A 24-year-old woman was referred to our interventional radiology unit from another hospital for possible embolization of a large left renal pseudoaneurysm that was considered as high risk for surgery. The patient had history of diffuse abdominal pain with enlarging abdominal girth. On general examination, she was of thin built and emaciated with significant pallor. On examining, there were no characteristic skin lesions. She was having tachycardia, and a lump was palpable, which extended from left hypochondrium to left lumbar region approximately 10 cm in length craniocaudally and 9 cm across extending up to the umbilicus. She had low hemoglobin at 6.4 g/dL and a slightly raised total leucocyte count of 12,000/mL. Abdominal ultrasonography using Logiq P5 ultrasound system (General Electric Healthcare) with 3.5 to 5 MHz showed bilateral enlarged kidneys. Right kidney shows well-defined three hyperechoic lesions of varying sizes suggestive of fat as main content and left kidney shows well-defined heteroechoic lesion with large pseudoaneurysm occupying upper two-thirds of parenchyma ([Fig. 1A, B]). Digital subtraction angiography (DSA) using BV Endura C-arm X-ray machine (Philips) confirmed the large left renal pseudoaneurysm ([Fig. 2C, E]) along with significant tumor vascularity. Selective embolization of the tumor mass with polyvinyl alcohol (PVA) particles (PVA 300, Cook Medical) was done. Following this closure of the artery feeding, the pseudoaneurysm was attempted using 4-mm, 5 cm-fibered stainless steel coils (Cook) and 50% N-butyl cyanoacrylate (Endocryl, Samarth Pharmaceutical): Lipiodol (Gurbet Laboratories) mixture Endocryl glue. Attempts to occlude the feeding artery failed due to high flow, and the coils were dislodged into the pseudoaneurysm ([Fig. 2F]). Next day ultrasound and contrast-enhanced CT (CECT) (128 multislice SOMATOM Definition AS; Siemens AG) showed the formation of a large intracavitory thrombus ([Fig. 3A, D]). The patient also developed post embolization fever and pain that was managed with antibiotics and nonsteroidal anti-inflammatory drugs (NSAIDs). The patient was planned for repeat embolization of the pseudoaneurysm along with either a vascular plug or using a balloon percutaneous transluminal angioplasty (PTA) catheter-assisted flow arrest during embolization coil deployment. However, before we could proceed, the patient started complaining worsening of the pain on the day 5, followed by cardiac arrest possibly from sudden severe internal hemorrhage due to rupture of the pseudoaneurysm.
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Discussion
Angiomyolipoma is known to be more prevalent in females. Some studies have suggested that AML can present in a wide age range from 19 to 93 years with overall prevalence being to as high as 0.44%.[7] The tumor consists of smooth muscles, adipose tissue, and malformed blood vessels as main components making it a triphasic tumor as described pathologically.[1] Up to 80% of AMLs occur sporadically, and whereas most of them present as classic AML with abundant detectable fat on imaging, the rest few may show very small amount of fat.[1] AML is commonly associated with aneurysm formation, seen in as many as 76% of the patients.[8]
The predictors of rupture include tumor and aneurysm sizes. When tumors sized 4 cm or larger and 6 cm or larger were used as predictors of rupture, sensitivity and specificity, were 100% and 38%, respectively, for the former criterion and 100% and 67% for the latter criterion. Mean aneurysm size was significantly larger in the group with ruptured tumor (13.3 ± 6.2 mm; range: 5–22 mm) than in the group with unruptured tumor (2.4 ± 2.9 mm; range: 2–11 mm). In their study of the eight ruptured aneurysms, all were at least 5 mm in sizes, and if aneurysms sized 5 mm or larger were used as criteria, rupture can be predicted with a sensitivity and specificity of 100% and 86%, respectively.[8] Our case records an aneurysmal size of 10.1 cm × 10.8 cm, which to our knowledge is one of the largest aneurysms seen in a renal AML. Though the cause of possible aneurysmal rupture in our case is not determined, we hypothesized that the intra-aneurysmal thrombosis post attempted coiling might have led to a pathophysiologic cascade leading to rupture of the aneurysm.
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Conclusion
Angiomyolipoma is a common tumor involving the kidneys and presents with varied clinical symptoms that may be associated with pseudoaneurysms. As discussed before, size of the pseudoaneurysm determines the probability of rupturing. As happened in this case in which the patient suddenly went into hypovolemic shock due to rupture of aneurysm, these cases need immediate intervention for decreasing the mortality.
Grant
No grant taken for the said study.
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Conflict of Interest
None.
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References
- 1 Jinzaki M, Silverman SG, Akita H, Nagashima Y, Mikami S, Oya M. Renal angiomyolipoma: a radiological classification and update on recent developments in diagnosis and management. Abdom Imaging 2014; 39 (03) 588-604
- 2 Johnson SR, Cordier JF, Lazor R. et al; Review Panel of the ERS LAM Task Force. European Respiratory Society guidelines for the diagnosis and management of lymphangioleiomyomatosis. Eur Respir J 2010; 35 (01) 14-26
- 3 Cook JA, Oliver K, Mueller RF, Sampson J. A cross sectional study of renal involvement in tuberous sclerosis. J Med Genet 1996; 33 (06) 480-484
- 4 Siegel CL, Middleton WD, Teefey SA, McClennan BL. Angiomyolipoma and renal cell carcinoma: US differentiation. Radiology 1996; 198 (03) 789-793
- 5 Meher R, Lynser D, Handique A. et al. Spontaneous giant pseudoaneurysm in a renal angiomyolipoma associated with tuberous sclerosis complex. Clin Case Rep Rev 2016; 2 (06) 2
- 6 Bosniak MA, Megibow AJ, Hulnick DH, Horii S, Raghavendra BN. CT diagnosis of renal angiomyolipoma: the importance of detecting small amounts of fat. AJR Am J Roentgenol 1988; 151 (03) 497-501
- 7 Fittschen A, Wendlik I, Oeztuerk S. et al. Prevalence of sporadic renal angiomyolipoma: a retrospective analysis of 61,389 in- and out-patients. Abdom Imaging 2014; 39 (05) 1009-1013
- 8 Yamakado K, Tanaka N, Nakagawa T, Kobayashi S, Yanagawa M, Takeda K. Renal angiomyolipoma: relationships between tumor size, aneurysm formation, and rupture. Radiology 2002; 225 (01) 78-82
Address for correspondence
-
References
- 1 Jinzaki M, Silverman SG, Akita H, Nagashima Y, Mikami S, Oya M. Renal angiomyolipoma: a radiological classification and update on recent developments in diagnosis and management. Abdom Imaging 2014; 39 (03) 588-604
- 2 Johnson SR, Cordier JF, Lazor R. et al; Review Panel of the ERS LAM Task Force. European Respiratory Society guidelines for the diagnosis and management of lymphangioleiomyomatosis. Eur Respir J 2010; 35 (01) 14-26
- 3 Cook JA, Oliver K, Mueller RF, Sampson J. A cross sectional study of renal involvement in tuberous sclerosis. J Med Genet 1996; 33 (06) 480-484
- 4 Siegel CL, Middleton WD, Teefey SA, McClennan BL. Angiomyolipoma and renal cell carcinoma: US differentiation. Radiology 1996; 198 (03) 789-793
- 5 Meher R, Lynser D, Handique A. et al. Spontaneous giant pseudoaneurysm in a renal angiomyolipoma associated with tuberous sclerosis complex. Clin Case Rep Rev 2016; 2 (06) 2
- 6 Bosniak MA, Megibow AJ, Hulnick DH, Horii S, Raghavendra BN. CT diagnosis of renal angiomyolipoma: the importance of detecting small amounts of fat. AJR Am J Roentgenol 1988; 151 (03) 497-501
- 7 Fittschen A, Wendlik I, Oeztuerk S. et al. Prevalence of sporadic renal angiomyolipoma: a retrospective analysis of 61,389 in- and out-patients. Abdom Imaging 2014; 39 (05) 1009-1013
- 8 Yamakado K, Tanaka N, Nakagawa T, Kobayashi S, Yanagawa M, Takeda K. Renal angiomyolipoma: relationships between tumor size, aneurysm formation, and rupture. Radiology 2002; 225 (01) 78-82