Spontaneous Rupture of a Renal Artery Aneurysm Presenting as Gross Hematuria

RIU0489_12-07.qxd 12/21/10 7:43 PM Page e193 CASE REVIEW Spontaneous Rupture of a Renal Artery Aneurysm Presenting as Gross Hematuria Shaun E.L. Wason, MD,1 Thomas Schwaab, MD, PhD2 1 Division of Urology, Dartmouth-Hitchcock Medical Center, Lebanon, NH; 2Roswell Park Cancer Center Institute, Buffalo, NY Renal artery aneurysms (RAAs) are localized dilations of the renal artery and/or its branches. They are being found with increasing frequency as a result of unrelated abdominal imaging or on workup for hypertension. They are rarely symptomatic; however, they can be a cause of life-threatening hematuria. Discussed is the case of a previously healthy 46-year-old man presenting with flank pain and gross hematuria. It is imperative for the practicing urologist to be aware of the appropriate evaluation and management of RAAs. [Rev Urol. 2010;12(4):e193-e196 doi: 10.3909/riu0489] © 2010 MedReviews®, LLC Key words: Renal artery aneurysm • Abdominal aortography • Gross hematuria • Pseudoaneurysm he patient is a healthy 46-year-old man with no prior history of medical problems who developed the acute onset of left flank pain and gross hematuria 1 day after riding on a wooden roller coaster. He presented to the emergency room 6 days later for evaluation and was found to be anemic with a hemoglobin level of 6.7 and hematocrit level of 19. He was hemodynamically stable. Computed tomographic urogram demonstrated hyperattenuation in the left collecting system and a large clot in the bladder (Figure 1). On arterial phase, there was evidence of an enhancing 3-cm left lower pole renal mass. Magnetic resonance imaging/magnetic resonance angiography (MRI/MRA) confirmed these findings T VOL. 12 NO. 4 2010 REVIEWS IN UROLOGY e193 RIU0489_12-07.qxd 12/21/10 7:43 PM Page e194 Spontaneous Rupture of a Renal Artery Aneurysm continued A B Figure 1. (A) Computed tomographic urogram of the abdomen/pelvis demonstrated hyperattenuation in the left collecting system and (B) a large filling defect in the left renal pelvis and bladder suggestive of clot. (Figure 2). Cystoscopy and left ureteroscopy revealed active bleeding from the left renal pelvis without a clear identifiable source. An arteriogram demonstrated a 22-mm pseudoaneurysm in the lower pole of the left kidney. This was coiled off selectively and the bleeding stopped immediately. Discussion Renal artery aneurysms (RAA) are localized dilations of the renal artery and/or branches. It was the first disease process of the renal artery to be identified and has historically been considered a rare phenomenon until the widespread use of angiography.1 In 1957, 141 cases of RAA had been reported in the literature1 and by 1967, arteriovenous/microaneurysms.5 Saccular are the most common and represent 70% to 75% of all RAAs.1,4,5 Intraparenchymal RAAs are rare and account for  10% of all RAAs.4,6 Although rare, there has been a recent increase in the discovery of renal arteriovenous fistulas secondary to trauma, inflammation, renal surgery, and percutaneous needle biopsy.7 Approximately 75% of renal arteriovenous fistulas are acquired and easily identifiable by their cirsoid configuration.4 These aneurysms account for 17% of all RAAs and do have the tendency for rupture.4 The overall incidence of RAA in autopsy studies ranges from 0.01% to 0.3%1,5 and has even been reported to be as high as 9.7% in one autopsy study2; however, more recent literature Approximately 75% of renal arteriovenous fistulas are acquired and easily identifiable by their cirsoid configuration. These aneurysms account for 17% of all RAAs and do have the tendency for rupture. this number had risen to well over 300.2 A true aneurysm is a balloonlike dilation of all layers of the vessel wall, whereas a false (pseudo) aneurysm is derived from tissues surrounding the arteries.1,3,4 There are 4 basic structural types: saccular, fusiform, dissecting, and has demonstrated that the overall incidence ranges between 0.01% to 1%.6,7 This increases to 2.5% when only patients with hypertension are considered4,6 and as high as 39% in patients with hypertension unresponsive to medical therapy.8 The mean age at diagnosis is age 60 years, occurs Figure 2. Magnetic resonance imaging/magnetic resonance angiography of the abdomen/pelvis demonstrated enhancement of a left lower pole renal mass. e194 VOL. 12 NO. 4 2010 REVIEWS IN UROLOGY RIU0489_12-07.qxd 12/21/10 7:43 PM Page e195 Spontaneous Rupture of a Renal Artery Aneurysm more commonly in men, and is primarily located on the right.2,5 RAAs can be either congenital or acquired. Congenital RAAs have been associated with autosomal dominant polycystic disease, fibromuscular dysplasia, and tuberous sclerosis.5 Congenital RAAs are frequently located at the bifurcation of the renal arteries and are typically of the fusiform type.1,4 Acquired etiologies include longstanding untreated hypertension, atherosclerosis, blunt7,9 and penetrating6 trauma, recent surgical manipulation (open, laparoscopic, and/or endovascular),11 angiomyolipomas, infectious (ie, mycotic),12 polyarteritis ing to hemodynamic instability.2,4,10,13 Ecchymosis, a palpable or pulsatile abdominal mass, and/or bruits are rare presenting symptoms.14 A thorough history and physical examination cannot be overemphasized, specifically addressing any previous history of trauma, as there can often be a substantial delay from months to years from the initial insult.9 Imaging is required to confirm the diagnosis of a RAA. In one series, only 66% of excretory urograms were diagnostic or suggestive of the presence of a renovascular lesion, whereas angiography was 100% diagnostic.2,4,10,14 Although angiography is Although angiography is the gold standard, perhaps the best noninvasive test to evaluate location, size, structure, and relation to nearby organs is CT/MRA. nodosa,2 malignancy, coagulopathy, radiation, and/or cyclophosphamide use.2 Acquired RAAs have a highly variable location1,6 and size (1 to 10 cm), although most ( 90%) are smaller than 2 cm.5 The risk of rupture is thought to vary inversely with size, and most investigators agree that aneurysms larger than  2 cm are more likely to undergo rupture.6 The rupture rate occurs in approximately 30% of cases, with mortality greater than 20%.4,6 RAAs are frequently asymptomatic, especially in children.1 Most RAAs are discovered on a workup for hypertension (55%), and are more frequently being discovered incidentally during unrelated abdominal imaging (ie, radiography, color Doppler ultrasound, computed tomography [CT], MRI) or angiography.5 When patients do present with symptoms, they usually present with flank pain and hematuria that can range from mild microscopic hematuria to gross hemorrhage lead- the gold standard, perhaps the best noninvasive test to evaluate location, size, structure, and relation to nearby organs is CT/MRA.6 In one study, MRA was able to distinguish between aneurismal-type malformations with a sensitivity, specificity, and accuracy of 78%, 100%, and 91%, respectively.15 Small cirsoid-type malformations (grade 1   2 cm) were not detected in 2 patients. Other imaging modalities that can give clues to the diagnosis include Doppler ultrasound, contrast-enhanced CT, and nuclear scintigraphy.8,10,12 complications include dissection, arterial thrombosis, renal infarction, showering of emboli, obstructive uropathy, erosion, and/or spontaneous rupture with hemorrhage.4,7,16 We report a case of spontaneous renal artery aneurysm rupture into the collecting system presenting as massive gross hematuria in a previously healthy male without prior history of hypertension, renal surgery, or trauma. Severe hematuria resulting from rupture of the RAA into the renal pelvis is fortunately a rare event. Indications for treatment include hemorrhage, uncontrolled hypertension, pain, progressive enlargement, presence of an arteriovenous fistula, size  2 to 2.5 cm, or  1 cm in a female of childbearing age.2,4,16 Currently, endovascular surgery is the intervention of choice in elective or emergent circumstances.6,7,10,17 Much literature has surfaced in recent years demonstrating acceptable feasibility and results with endovascular treatment.6,7,17 Accepted endovascular treatments include embolization (ie, gelfoam, coils, alcohol) or stenting across the aneurysm.6,17 There have also been case reports of successful management of RAAs with percutaneous thrombin injection directly into the aneurysm.11 Factors that may preclude endovascular management are size and multiplicity, although there have been reports of successful endovascular management of large (10 cm) RAAs endovascularly.17,18 RAAs that are not amenable to endovascular therapy may undergo Although most RAAs are small and asymptomatic, growth is unpredictable and complications may result as they enlarge. Although most RAAs are small and asymptomatic, growth is unpredictable and complications may result as they enlarge. Frequently cited nephrectomy, partial nephrectomy, renal artery grafting, aneurysmectomy, autotransplantation, and/or renal artery ligation.4,13,19-22 VOL. 12 NO. 4 2010 REVIEWS IN UROLOGY e195 RIU0489_12-07.qxd 12/21/10 7:43 PM Page e196 Spontaneous Rupture of a Renal Artery Aneurysm continued The largest series of renal artery surgery, spanning 35 years, was reported by Henke and colleagues23 on 121 patients undergoing RAA surgical repair at the University of Michigan. There were no perioperative mortalities; however, there were 8 unplanned nephrectomies. A retrospective review by Pfeiffer and colleagues22 of 94 patients with RAAs undergoing open repair resulted in 1 perioperative mortality, a 17% morbidity rate, and a 97% primary success rate. Similar results were achieved by English and colleagues24 when they examined 72 RAAs over a 16-year period. There was 1 perioperative mortality, a 12% morbidity rate, and a 96% primary success rate. References 1. 2. 3. 4. 5. 6. 7. 8. Conclusions Although rare, the diagnosis of RAA is being made more frequently with more patients undergoing abdominal aortography and abdominal imaging for unrelated causes. It is imperative for the practicing urologist and clinician to be aware of life-threatening causes of gross hematuria, appropriate evaluation and imaging of suspected RAAs, endovascular management, operative indications, and techniques. 9. 10. 11. Poutasse EF. Renal artery aneurysm: report of 12 cases, two treated by excision of the aneurysm and repair of renal artery. J Urol. 1957;77:697-708. Glass PM, Uson AC. Aneurysms of the renal artery: a study of 20 cases. J Urol. 1967;98: 285-292. Bakir AA, Patel SK, Schwartz MM, Lewis EJ. Isolated dissecting aneurysm of the renal artery. Am Heart J. 1978;96:92-96. Cerny JC, Chang CY, Fry WJ. Renal artery aneurysms. Arch Surg. 1968;96:653-663. Tham G, Ekelund L, Herrlin K, et al. Renal artery aneurysms. Natural history and prognosis. Ann Surg. 1983;197:348-352. Porcaro AB, Migliorini F, Pianon R, et al. Intraparenchymal renal artery aneurysms. Case report with review and update of the literature. Int Urol Nephrol. 2004;36:409-416. Giannopoulos A, Manousakas T, Alexopoulou E, et al. Delayed life-threatening haematuria from a renal pseudoaneurysm caused by blunt renal trauma treated with selective embolization. Urol Int. 2004;72:352-354. De Wilde V, Devue K, Vandenbroucke F, et al. Rupture of renal artery aneurysm into the renal pelvis, clinically mimicking renal colic: diagnosis with multidetector CT. Br J Radiol. 2007;80:e262-e264. Lindekleiv H, Haro S, Nordhus K, et al. Renal artery pseudoaneurysm secondary to blunt trauma nine years earlier: case report and review of the literature. Scand J Urol Nephrol. 2008;42:488-491. Dulabon LM, Singh A, Vogel F, Moinzadeh A. Intrarenal pseudoaneurysm presenting with microscopic hematuria and right flank pain. Can J Urol. 2007;14:3588-3591. Gupta V, Galwa R, Khandelwal N, Bapuraj JR. Postpyelolithotomy renal artery pseudoaneurysm management with percutaneous thrombin injection: a case report. Cardiovasc Intervent Radiol. 2008;31:422-426. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. Ohebshalom MM, Tash JA, Coll D, et al. Massive hematuria due to right renal artery mycotic pseudoaneurysm in a patient with subacute bacterial endocarditis. Urology. 2001;58:607. McKenzie CG. Rupture of a renal artery aneurysm presenting with severe haematuria and clot retention. Br J Surg. 1967;54:660-662. Bulbul MA, Farrow GA. Renal artery aneurysms. Urology. 1992;40:124-126. Takebayashi S, Ohno T, Tanaka K, et al. MR angiography of renal vascular malformations. J Comput Assist Tomogr. 1994;18:596-600. Hughes JH, Stanisic TH, Buster D, Nagle RB. Massive nontraumatic hematuria: a challenge demanding immediate action. Postgrad Med. 1980;67:97-106. Gutta R, Lopes J, Flinn WR, Neschis DG. Endovascular embolization of a giant renal artery aneurysm with preservation of renal parenchyma. Angiology. 2008;59:240-243. Ishizuka O, Takayama F, Sone S. Large renal aneurysm successfully treated by percutaneous embolization using detachable steel coils. Int J Urol. 2006;13:993-994. Bastounis E, Pikoulis E, Georgopoulos S, et al. Surgery for renal artery aneurysms: a combined series of two large centers. Eur Urol. 1998;33:22-27. Dzsinich C, Gloviczki P, McKusick MA, et al. Surgical management of renal artery aneurysm. Cardiovasc Surg. 1993;1:243-247. Hupp T, Allenberg JR, Post K, et al. Renal artery aneurysm: surgical indications and results. Eur J Vasc Surg. 1992;6:477-486. Pfeiffer T, Reiher L, Grabitz K, et al. Reconstruction for renal artery aneurysm: operative techniques and long-term results. J Vasc Surg. 2003;37:293-300. Henke PK, Cardneau JD, Welling TH 3rd, et al. Renal artery aneurysms: a 35-year clinical experience with 252 aneurysms in 168 patients. Ann Surg. 2001;234:454-462; discussion 462-463. English WP, Pearce JD, Craven TE, et al. Surgical management of renal artery aneurysms. J Vasc Surg. 2004;40:53-60. Main Points • Renal artery aneurysms (RAAs) are localized dilations of the renal artery and/or branches. Saccular aneurysms are the most common form representing 70% to 75% of diagnosed RAAs; intraparenchymal RAAs are rare and account for only  10%. • Most RAAs are discovered during workup for hypertension (55%), and are more frequently being discovered incidentally during unrelated abdominal imaging (ie, radiography, color Doppler ultrasound, computed tomography, magnetic resonance imaging) or angiography. When patients do present with symptoms, they are usually in the form of flank pain and hematuria that can range from mild microscopic hematuria to gross hemorrhage that leads to hemodynamic instability. • Indications for RAA treatment include hemorrhage, uncontrolled hypertension, pain, progressive enlargement, presence of an arteriovenous fistula, size  2 to 2.5 cm, or  1 cm in a female of childbearing age. Currently, endovascular surgery is the intervention of choice in elective or emergent circumstances. • Health care practitioners should be aware of life-threatening causes of gross hematuria, appropriate evaluation and imaging of suspected RAAs, endovascular management, operative indications, and techniques. e196 VOL. 12 NO. 4 2010 REVIEWS IN UROLOGY