Caval and ureteral obstruction secondary to aninflammatory abdominal aortic aneurysmVikram S. Kashyap, MD, Raymond Fang, MD, Colleen M. Fitzpatrick, MD, and Ryan T. Hagino, MD,San Antonio, Tex

Inflammatory abdominal aortic aneurysms (IAAA) represent 3% to 10% of all abdominal aortic aneurysms. Obstructiveuropathy is a well-described feature of IAAAs, but venous complications are unusual secondary to IAAA. The authorsreport a patient presenting with acute renal failure and deep venous thrombosis secondary to an IAAA. We believe thisrepresents the first case of an IAAA manifesting as combined inferior vena cava compression and associated obstructiveuropathy. Successful operative repair was performed. With resolution of the retroperitoneal inflammation, long-termfollow-up revealed spontaneous release of both ureteral and caval compression. (J Vasc Surg 2003;38:1416-21.)

Inflammatory abdominal aortic aneurysms (IAAA) rep-resent a variant of aortic aneurysms. Up to 80% of patientspresent with symptoms of abdominal, back, or flank painthat may mimic a leaking or ruptured aneurysm. Thickenedaneurysm wall, retroperitoneal fibrosis with resulting pain,and adhesions to adjacent structures are common featuresof IAAA. Ureteral entrapment is a well-recognized compli-cation in the setting of IAAA. Even though adhesions tothe inferior vena cava (IVC) may occur, symptomatic ve-nous compression is rare. We present a case of combinedcaval and ureteral compression presenting as deep venousthrombosis (DVT) and acute renal failure.

CASE REPORT

A 69-year-old man presented to a primary care provider with a3-week history of painless, progressive “left leg swelling.” Theswelling began at his left foot and migrated proximally to the leftthigh. He reported no history of trauma or recent travel, but headmitted to sitting at a computer for 6 to 8 hours daily. He deniedany chronic illness and took no prescription medications. Hepreviously smoked half a pack per day for 54 years until successfullyquitting 1 year earlier. His physical examination was significant fora blood pressure of 200/100, a pulsatile abdominal mass, anabdominal bruit, and pitting edema to the left thigh. Laboratorystudies revealed a BUN of 28 mg/dL and Creatinine of 2.5mg/dL. Chest radiographs demonstrated a right upper lobe den-sity, and Duplex ultrasound showed the presence of extensive leftlower extremity deep vein thrombosis in both the femoral andpopliteal venous systems. He was admitted for anticoagulant ther-apy and for evaluation of the right lung mass, which eventuallyproved to be a benign granuloma. Because of his renal insufficiency

and hypertension, renal artery stenosis was suspected and a renalDuplex ultrasound was obtained. The study did not reveal renalartery stenosis, but instead it revealed bilateral hydroureter andhydronephrosis flanking a 7-cm abdominal aortic aneurysm. Thevascular surgery service was consulted. Noncontrast abdominalcomputed tomography (CT) confirmed the aneurysm size (Fig 1),and magnetic resonance angiography further defined the anatomy.These imaging studies and his erythrocyte sedimentation rate(ESR) (67 mm, normal 0-15) suggested an IAAA. Bilateral ure-teral stents were placed, and then aortic endoaneurysmorraphy wasundertaken via a transabdominal approach. With minimal dissec-tion, the glistening white aneurysm sac was exposed in the retro-peritoneum (Fig 2). Mobilization of the adherent duodenum wasavoided, and the neck of the aneurysm was clamped laterallythrough a window in the adhesions after systemic heparinization. A16-mm knitted Dacron tube graft was placed, and the aneurysmsac was closed over the graft after its placement. Postoperatively,anticoagulation was suspended because of bleeding and a de-creased platelet count. IVC filter placement was attempted, but itwas aborted after venography demonstrated caval compression(Fig 3). Anticoagulation with Heparin was resumed and main-tained with warfarin sodium for 6 months. The patient’s recoverywas unremarkable, his leg swelling diminished, and his serumCreatinine fell to 1.7 mg/dL. The ureteral stents were removed 9months postoperatively after normal retrograde pyelograms. Anabdominal CT scan, obtained 2.5 years postoperatively, demon-

From the Division of Vascular Surgery, Wilford Hall Medical Center,Lackland Air Force Base.

Competition of interest: noneThe views expressed in this report are those of the authors and do not reflect

official policy of the Department of Defense or other Departments of theUS Government.

Reprint requests: Lt Col Vikram S. Kashyap, MD, 859 MSGS/MCSG, 2200Bergquist Dr, Ste 1, Lackland AFB, TX 78236-5300 (e-mail:vikram.kashyap@lackland.af.mil).

Copyright © 2003 by The Society for Vascular Surgery.0741-5214/2003/$30.00 � 0doi:10.1016/S0741-5214(03)00795-X

Selected references on IAAA

Author Year

Patients(IAAA/all AAA)

Ureteralobstruction

N (%)

Venousobstruction

or DVT

Crawford et al 7 1985 30/NA 7 (23) 0Pennell et al 6 1985 127/2816 13 (10) 0Sterpetti et al 8 1989 30/486 6 (20) 0Boontje et al 9 1990 45/517 9 (20) 0Lindblad et al 10 1991 98/2026 19 (19) 0Stella et al 5 1993 40/779 10 (25) 0Von Fritschen et al 11 1999 42/1035 9 (21) 0Total 412/NA 73 (18) 0

IAAA, Inflammatory abdominal aortic aneurysm; AAA, Abdominal aorticaneurysm; DVT, Deep venous thrombosis; NA, not available.

1416

strated a decreased size of the aneurysm sac and a small amount ofresidual perianeurysmal fibrosis (Fig 4, A and B). However, bothIVC and ureters were free from compression and the cava hadreturned to normal size.

DISCUSSION

James reported the first case of IAAA in 1935,1 but itwas 20 years later that the first successful surgical repair wasreported and another 20 years before Walker coined theterm “inflammatory aneurysm.” He characterized IAAA asa distinct clinical and pathological entity with “an unusuallythick wall surrounded by extensive fibrous adhesions in-volving adjoining tissues and structures.”2 More recently,the belief that IAAA is a distinct entity has been supplantedby the belief that these aneurysms are a variant of the typicalaneurysm with elements of retroperitoneal fibrosis.

The precise etiology of IAAAs remains controversial,and previously held hypotheses include inflammation inresponse to subclinical blood extravasation or fibrosis re-sulting from compression of the retroperitoneal lymphaticsby the aneurysm.3 Most investigators now believe thatIAAA is an extreme variant of typical aneurysms and havesought to identify an antigen within the aneurysm wall thatincites an inflammatory process. Although all aneurysmselicit some degree of inflammatory response, interplay be-tween multiple risk factors may ultimately determine the

degree of this response that distinguishes IAAAs. Interest-ingly, a common feature of IAAAs is that the inflammatoryprocess seems to halt and subside when exclusion of bloodflow via operative repair is accomplished. This is mostcommonly manifested as a spontaneous lysis of previouslytrapped structures, especially the ureter. Furthermore, in arecent study, postoperative serial CT scans confirmed re-gression of the retroperitoneal fibrosis in patients afterIAAA repair.4 Ureteral entrapment and constriction occursin 20% to 44% of cases and approximately one half of thesepatients will present with obstructive uropathy.3 Ureterol-ysis at the time of initial operative repair remains controver-sial because subsequent imaging of patients shows thatureteral obstruction generally resolves without interventionafter aneurysm repair.5 Most patients have partial or com-plete resolution of their ureteral obstruction. However,ureterolysis may be necessary for patients that fail to resolvetheir ureteral obstruction postoperatively despite pro-longed drainage via ureteral stents or percutaneous cathe-ters. Interestingly, complete regression of the inflammationis more likely in IAAAs with a high cellular density found onhistological analysis of the aneurysm wall.5

Gross pathologic features associated with IAAAs in-clude a shiny-white porcelain appearance with thickenedanterior and lateral walls and fibrous retroperitoneal exten-sion. Adhesion of adjacent structures is common, with

Fig 1. Cross-sectional CT scan demonstrates large abdominal aortic aneurysm with thickened walls characteristic ofIAAA. The line points to the inflammatory halo of the aneurysm.

JOURNAL OF VASCULAR SURGERYVolume 38, Number 6 Kashyap et al 1417

duodenal involvement expected in all cases and adhesionsto the IVC and the left renal vein frequently found.6

Venous complications, however, have not been extensivelyreported. Multiple large series of IAAAs occasionally doc-ument adhesions to the IVC, but none reveal caval obstruc-tion or DVT as a presenting sign (Table). These same seriesfind ureteral obstruction in 18% of cases. Due to the exten-sive retroperitoneal adhesions, operative complications ofinadvertent caval or left renal vein injury occasionally occur.Leseche and colleagues12 described 1 patient out of 17treated for IAAA having IVC involvement and expiring onpostoperative day 4 from a pulmonary embolism. That caseseemed to represent a postoperative DVT.

Scattered case reports have documented venous com-pression from IAAA. Houle and Ellwood described a pa-tient presenting with pitting edema secondary to cavalobstruction from an 8-cm IAAA.13 Extrinsic compressionof the inferior vena cava by an IAAA causing bilateral lowerextremity edema was also reported by Braxton and col-leagues.14 Similar to this report, the caval compressionresolved after successful operative treatment of the IAAA.However, in contradistinction to this report, the diagnosisof caval compression was made preoperatively and an opera-tive debridement of the IAAA to free the IVC was performed.

Most patients with IAAAs present with symptoms andwith characteristic findings on radiological images. In this

Fig 2. Operative photograph reveals glistening white surface typical of the retroperitoneal fibrosis seen in IAAA.

JOURNAL OF VASCULAR SURGERYDecember 20031418 Kashyap et al

patient, we believe the inflammatory reaction extending tothe vena cava caused compression and manifested as a leftlower extremity deep venous thrombosis, which may rep-resent a variant of May–Thurner Syndrome. The deepvenous thrombosis was treated with anticoagulant therapyonly, as inferior vena cava filter placement was not possiblesecondary to the distorted caval anatomy. Additionally, thispatient had an associated obstructive uropathy, a morecommonly reported complication. After aneurysm repair(which did not include ureterolysis), his ureteral obstruc-tion resolved without further intervention. Also, caval com-

pression resolved, and he has had no further thromboem-bolic events and has not required anticoagulation.

Ureteral compression is a well-delineated facet ofIAAA. A review of the literature indicates that venousadhesions are common, but that venous obstruction is rare.This indicates that the IVC is resilient in the face of retro-peritoneal fibrosis secondary to IAAA. This case illustratesthat the retroperitoneal fibrosis that encompasses the uretersimilarly can affect the vena cava. More importantly, afteroperative repair of the IAAA, the caval compression isrelieved as the retroperitoneal fibrosis subsides and appears

Fig 3. Inferior vena cavagram at the time of attempted IVC filter placement shows severe extrinsic compression of IVCby IAAA.

JOURNAL OF VASCULAR SURGERYVolume 38, Number 6 Kashyap et al 1419

Fig 4. A and B, CT scans obtained after successful operative repair of IAAA reveal a decreased size of the aneurysm sacand a small amount of residual perianeurysmal fibrosis. IVC is free from compression and has returned to normal size(lines point to the IVC).

JOURNAL OF VASCULAR SURGERYDecember 20031420 Kashyap et al

to indicate that, analogous to the ureter, spontaneous lysisof caval compression can occur and no operative decom-pression of the cava is necessary in these cases.

REFERENCES

1. James TGI. Uremia due to aneurysm of the abdominal aorta. Br J Urol1935;7:157-161.

2. Walker DI, Bloor K, Williams G, Gillie I. Inflammatory aneurysms ofthe abdominal aorta. Br J Surg 1972;59:609-14.

3. Rasmussen T, Hallett JW. Inflammatory aortic aneurysms: a clinical reviewwith new perspectives in pathogenesis. Ann Surg 1997;225:155-64.

4. Pistolese GR, Ippoliti A, Mauriello A, Pistolese C, Pocek M, SimonettiG. Postoperative regression of retroperitoneal fibrosis in patients withinflammatory abdominal aortic aneurysms: evaluation with spiral com-puted tomography. Ann Vasc Surg 2002;16:201-9.

5. Stella A, Gargiulo M, Faggioli GL, Bertoni F, Cappello I, Brusori S, etal. Postoperative course of inflammatory abdominal aortic aneurysms.Ann Vasc Surg 1993;7:229-38.

6. Pennell RC, Hollier LH, Lie JT, Bernatz PE, Joyce JW, Pairolero PC, etal. Inflammatory abdominal aortic aneurysms: a thirty-year review. JVasc Surg 1985;2:859-69.

7. Crawford JL, Stowe CL, Safi HJ, Hallman CH, Crawford ES. Inflam-matory aneurysms of the aorta. J Vasc Surg 1985;2:113-24.

8. Sterpetti AV, Hunter WJ, Feldhaus RJ, Chasan P, McNamara M,Cisternino S, et al. Inflammatory aneurysms of the abdominal aorta:incidence, pathologic, and etiologic considerations. J Vasc Surg 1989;9:643-50.

9. Boontje AF, van den Dungen JJ, Blanksma C. Inflammatory abdominalaortic aneurysms. J Cardiovasc Surg 1990;31:611-6.

10. Lindblad B, Almgren B, Bergqvist D, Eriksson I, Forsberg O, GlimakerH, et al. Abdominal aortic aneurysm with perianeurysmal fibrosis:experience from 11 Swedish vascular centers. J Vasc Surg 1991;13:231-9.

11. Von Fritschen U, Malzfeld E, Clasen A, Kortmann H. Inflammatoryabdominal aortic aneurysm: a postoperative course of retroperitonealfibrosis. J Vasc Surg 1999;30:1090-8.

12. Lesche G, Schaetz A, Arrive L, Nussaume O, Andreassian B. Diagnosisand management of 17 consecutive patients with inflammatory abdom-inal aortic aneurysm. Am J Surg 1992;164:39-44.

13. Houle BJC, Ellwood RA. Retroperitoneal fibrosis from aortic aneurysmcausing vena cava obstruction: a case report. Angiology 1982;33:64-6.

14. Braxton JH, Salander JM, Gomez ER, Conaway CW. Inflammatoryabdominal aortic aneurysm masquerading as occlusion of the inferiorvena cava. J Vasc Surg 1990;12:527-30.

Submitted Mar 25, 2003; accepted May 16, 2003.

JOURNAL OF VASCULAR SURGERYVolume 38, Number 6 Kashyap et al 1421