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The Journal of Emergency Medicine, Vol. 43, No. 3, pp. 431–434, 2012Copyright © 2012 Elsevier Inc.

Printed in the USA. All rights reserved0736-4679/$–see front matter

doi:10.1016/j.jemermed.2009.11.002

ClinicalCommunications: Adults

CASE REPORT: AORTOENTERIC FISTULA PRESENTING ASREPEATED HEMATOCHEZIA

Michael K. Doney, MD, MS and Gary M. Vilke, MD

Department of Emergency Medicine, University of California, San Diego Medical Center, San Diego, CaliforniaReprint Address: Gary M. Vilke, MD, UCSD Medical Center, Department of Emergency Medicine, 200 West Arbor Drive, Mail code

8676, San Diego, CA 92103

e Abstract—Background: Aortoenteric fistula (AEF) is arare but life-threatening condition in which expedient di-agnosis is often difficult. It arises from erosion of a segmentof aorta, usually an abdominal aortic aneurysm, into anadjacent portion of the gastrointestinal tract or between avascular graft of the aorta and an adjacent portion of thegastrointestinal tract. It can present as life-threatening up-per or lower gastrointestinal bleeding and is a surgicalemergency that requires rapid assessment, emergency re-suscitation, and definitive treatment. Case Report: To pres-ent the case of an 87-year-old man diagnosed with AEF inthe emergency department. A review of the literature fol-lows the case report. Conclusions: Aortoenteric fistula is arare diagnosis that can cause sudden life-threatening gas-trointestinal bleeding. © 2012 Elsevier Inc.

e Keywords—aortoenteric; fistula; hematochezia

INTRODUCTION

We present a case of an elderly man who was brought infor recurrent hematochezia. The diagnosis of aortoentericfistula (AEF) was made. Case management and a reviewof the literature are then presented.

CASE REPORT

Prehospital Care

An 87-year-old man presented to the emergency depart-ment (ED) from his home via paramedics. He reported an

RECEIVED: 15 July 2009; FINAL SUBMISSION RECEIVED: 21 O

CCEPTED: 8 November 2009

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episode of a large volume of bloody stool associated withnear syncope while on the toilet, followed by a fallduring which he sustained a forehead laceration. Hedenied loss of consciousness and was awake and alert onparamedic arrival. Paramedics reported a large volume ofblood on the patient’s bathroom floor, estimated at sev-eral hundred milliliters. The patient was initially hypo-tensive in the field, with a systolic blood pressure of 75mm Hg by palpation and a pulse of 65 beats/min. Theparamedics established venous access and gave the pa-tient a fluid bolus that had totaled 700 cc of 0.9% normalsaline by the time of arrival. In the ED, the patient’sarrival blood pressure was 115/85 mm Hg, with a pulseof 72 beats/min.

ED Presentation

Initial history reflected that the patient came to the EDonly at the insistence of his wife. He confirmed the reportof the paramedics. Additional history obtained includedthat the patient had a similar episode of hematocheziaapproximately 2 weeks prior, but had not sought medicalattention until now. He did not pass out at that time, butwas dizzy for a period after the episode. He deniedintercurrent rectal bleeding or melenotic stools. He de-nied hematemesis, abdominal pain, or weight loss. Ad-ditional review of systems was negative for fevers, chills,sweats, nausea, vomiting, chest pain, shortness of breath,orthopnea, dyspnea on exertion, bleeding gums, hema-

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432 M. K. Doney and G. M. Vilke

turia, easy bruising, headache, visual changes, or focalweakness or numbness.

The patient’s past medical history was notable for anuncomplicated abdominal aortic aneurysm repair approx-imately 8 years earlier. He had a history of hypertension,with his usual systolic blood pressure in the range of 140–150 mm Hg. The patient’s sole medication was an antihy-pertensive agent, which he was unable to recall. He deniedtaking any anticoagulants or antiplatelet agents. He hadundergone routine colonoscopy approximately 5–6 yearsearlier that he was told was normal.

Physical examination revealed an alert conversant el-derly man in no obvious distress. His initial ED vital signswere: temperature of 37.1°C (98.8°F), blood pressure115/85 mm Hg, pulse of 72 beats/min, respiratory rate of 18breaths/min, and an oxygen saturation of 98% on 2 Loxygen by nasal cannula. Notable findings included a small1.5-cm laceration on the right forehead, not bleeding at thetime of evaluation. His sclerae were anicteric. The rest ofhis head examination was unremarkable. His neck, lungs,heart, extremity, and neurological examinations were nor-mal. The abdominal examination revealed a large well-healed midline laparotomy scar. The abdomen was non-tender without palpable masses, abnormal pulsations, ororganomegaly. There were no rebound, guarding, or peri-toneal signs. Digital rectal examination revealed bloodmixed with stool that was confirmed with positive hemoc-cult testing. Anoscopy revealed no obvious bleeding sourceand no stool in the rectal vault. There was no active orongoing bleeding at the time of anoscopy.

ED Course

The patient agreed to have diagnostic studies performed,but stated emphatically that he would not undergo anyinterventions, such as surgery. His wife was present andconfirmed these statements to be consistent with hiswishes over the last several months. Initial laboratorystudies, including complete blood cell count, comprehen-sive metabolic panel including liver function tests, coag-ulation studies, and a type and cross-match for four unitsof packed red blood cells, were sent. A second large-boreintravenous catheter was placed.

Urgent consultation with a radiologist was obtainedgiven concern for a possible AEF. Although the patientwas relatively hypotensive in the ED, his vital signshad remained stable without examination evidence ofcontinued bleeding. A non-contrast computed tomog-raphy (CT) scan of the abdomen was obtained as thepatient was in acute renal failure.

The patient’s laboratory findings were: electrolytesnormal except for a bicarbonate of 20 mmol/L. His blood

urea nitrogen was 45 mg/dL, creatinine 3.7 mg/dL, and

glucose 158 mg/dL. His liver function tests were normal.White blood cells were 10.3 K/uL, hemoglobin 7.2 G/dL,hematocrit 21.6%, platelets 129 K/uL, mean corpuscularvolume 89 fL. Partial thromboplastin time was 29 s, pro-thrombin time 15 s, and international normalized ratio 1.49.

Upon the patient’s return to the ED from the Radiol-ogy suite, he developed a diminished level of conscious-ness with massive hematemesis. Vital signs revealed ablood pressure of 75/40 mm Hg and pulse of 90 beats/min. Previously ordered packed red blood cells wereimmediately available and the patient was emergentlytransfused. He additionally received boluses of normalsaline. The patient’s vital signs improved to a bloodpressure of 100/50 mm Hg, with a pulse of 85 beats/min.The patient’s mental status improved to baseline. AnEwald tube was placed, with return of 800 mL of bloodover the course of the next 10 min.

During this time, the radiographic report was ob-tained, with results consistent with AEF (Figures 1).Emergent vascular surgery consultation was obtained inthe ED. Given the patient’s continued refusal to undergosurgery and the poor surgical risk, the patient was pro-vided comfort care only and admitted to the floor.

Hospital Course

Ultimately, the patient’s clinical condition stabilizedand he agreed to undergo esophagogastroduodenoscopy

Figure 1. Marked tortuosity of the aorta is present. An aorticstent is in place with dissection flap (arrow). There is a loss ofthe fat plane between the aorta and the duodenum with recon-stitution of this tissue plane inferiorly. These findings are con-

sistent with the clinical diagnosis of aortoenteric fistula.

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Aortoenteric Fistula Presenting as Repeated Hematochezia 433

(EGD) the following day. The upper gastrointestinal tractto the third portion of the duodenum was visualizedwithout evidence of lesion. A diagnosis of secondaryAEF was made. The patient continued to refuse treat-ment and was discharged to home hospice care.

DISCUSSION

Background

An AEF is a rare but life-threatening condition inwhich expedient diagnosis is often difficult. It occursin two distinct fashions, termed “primary” and “sec-ondary.” A primary aortoenteric fistula (PAEF) arisesfrom erosion of a segment of aorta (often abdominalaortic aneurysm) into an adjacent portion of the gas-trointestinal tract. However, AEF is most commonlyseen as a delayed complication of aortic reconstructivesurgery with prosthetic or homograft use. A secondaryaortoenteric fistula (SAEF) occurs between the vascu-lar graft and an adjacent portion of the gastrointestinaltract, and is commonly associated with graft infection.However, SAEF has been rarely reported after endo-vascular aortic repair with stent grafting (1).

The incidence of SAEF is 0.36 –1.6% after graftplacement (2). The most common site of AEF forma-tion is the distal duodenum. The average elapsedtime between graft placement and formation of SAEFis 6 years; with a reported range of 2 weeks to � 10

ears (3).

linical Presentation

resenting signs and symptoms of AEF are variable. Thelassic triad of gastrointestinal hemorrhage, abdominalain, and a pulsatile abdominal mass is present in � 25%f patients (4). In fact, presentations may range fromassive gastrointestinal bleeding to the non-specific con-

titutional symptoms of graft infection only. Approxi-ately 70% of patients with PAEF will present with

ome form of gastrointestinal bleeding. Due to the ex-reme mortality risk of AEF, the presence of gastrointes-inal bleeding in the patient with known abdominal aorticneurysm or status post aortic graft placement must beonsidered AEF until proven otherwise. However, thesual cause of gastrointestinal bleeding in these patientsill be other unrelated gastrointestinal pathology more

ypical of the general population (2).SAEF may present with a more varied picture than

AEF. Gastrointestinal bleeding may be present, al-hough fever, malaise, leukocytosis, focal findings ofhronic wound or graft infection, or some combination of

hese may be the sole presentation (2).

Diagnosis

Diagnosis of AEF is challenging and occurs in only33–50% of patients before laparotomy (2). History andphysical examination coupled with a consideration forthe diagnosis of AEF is crucial to timely diagnosis and isoften the key parameter in defining the need for laparot-omy. The mainstay of diagnostic procedures is EGD andis often the initial study in the patient with suspectedAEF. Whereas the endoscopic appearance of AEF isvariable or may be absent, the exclusion of other causesof hematemesis is often key to the evaluative process (5).EGD may be readily performed at the bedside in unstablepatients, thus obviating the need to leave the ED. In thepresence of continued bleeding, however, endoscopymay be deferred to the surgical suite, or may, in fact, beimpossible due to profuse bleeding.

Contrast-enhanced CT scanning is an additional cru-cial diagnostic tool. CT allows visualization of the ret-roperitoneum, the perigraft tissues, and helps define therelationship between the gastrointestinal tract and graft.Findings of persisting perigraft air or fluid, loss of tissueplanes, adjacent bowel wall thickening or inflammation,and the presence of eroding graft or contrast material inthe bowel are associated with AEF (6). Abnormalities aremost often present on CT examinations, but absent frankfindings of graft erosion or contrast extravasation into thebowel, are frequently considered non-diagnostic (7).

Additional diagnostic modalities such as magnetic reso-nance imaging (MRI)/MR angiography, tagged white bloodcell studies, and angiography have been reported previ-ously. For MRI, sensitivity for perigraft soft tissue in-fection is increased relative to CT, but the decreasedspecificity for SAEF vs. normal post-operative changesin the 3–6 months after surgery limits its usefulness.Tagged white blood cell scans have excellent sensitivityfor graft infection, but poor specificity. Nuclear medicinemodalities do not uniquely identify AEF, but the findingof graft infection would mandate surgical intervention.Finally, angiography has been of limited utility in thediagnosis of AEF. Its principal benefit has been in sur-gical planning for the stable patient. These modalitiesseem to achieve their greatest usefulness when usedsubsequent to equivocal EGD (3,7–10).

Treatment

The treatment of AEF is surgical. The role of the emer-gency physician is primarily resuscitation and stabiliza-tion of the patient. Because AEF represents a source ofinfection, SAEFs are frequently associated with graftinfection, and hematogenous spread of bacteria repre-

sents a risk factor for post-operative complications, the

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434 M. K. Doney and G. M. Vilke

initiation of broad-spectrum antibiotics is indicated tocover enteric organisms (3). Permissive hypotension isappropriate until definitive treatment by a vascular sur-geon, given stability of end organ functioning (e.g., nor-mal mentation, no chest pain).

This case presented with the dilemma that the patientwas refusing surgical therapy. This puts the emergencyphysician in a challenging position. There are no reportsof patients who refuse surgical treatment who survive.Debonnaire et al. report 18 cases in Belgium with a100% mortality in untreated cases and a 29% survivalrate in those who were treated (11). Considerations fornon-operative treatment include blood products to cor-rect any coagulopathies. There are no studies or casereports that show a benefit of vasopressin or factor VII insuch a patient as well. Ultimately, despite attemptedstabilizing therapy, without the possibility of surgicalrepair, these therapies are just a finger in the hole of acrumbling dike and seem not to reverse the terminalnature of the patient who does not allow attemptedsurgical intervention.

CONCLUSION

ortoenteric fistula is a rare but highly lethal condition.ts presentation is exceedingly variable, and consider-tion of the diagnosis of AEF is required for timelyiagnosis. Endoscopic and radiographic adjuncts to di-

gnosis are frequently used but often do not yield defin-

itive results. Early consultation with a vascular surgeonis critical, and untreated, AEF seems to be uniformlyfatal.

REFERENCES

1. D’Othee BJ, Soula P, Otal P, et al. Aortoduodenal fistula afterendovascular stent-graft of an abdominal aortic aneurysm. J VascSurg 2000;31:190–5.

2. Kuestner LM, Reilly LM, Jicha DL, Ehrenfeld WK, Goldstone J,Stoney RJ. Secondary aortoenteric fistula: contemporary outcomewith use of extraanatomic bypass and infected graft excision. JVasc Surg 1995;21:184–95.

3. O’Brien S, Ernst C. Aortoenteric fistulas. In: Rutherford R, ed.Vascular surgery, 5th edn. Philadelphia, PA: Saunders; 2000:736 –75.

4. Kaushik SP, Cowlishaw JL. Primary aortoenteric fistula. AustN Z J Med 1998;28:471–2.

5. Kulling D. Aortoenteric fistula. Gastrointest Endosc 2000;51:723.6. Daly CA, Nott DM, Padley SP. Aortoduodenal fistula: appearances

on computed tomography. Aust N Z J Surg 1997;67:745–6.7. Busuttil SJ, Goldstone J. Diagnosis and management of aortoen-

teric fistulas. Semin Vasc Surg 2001;4:302–11.8. Spartera C, Morettini G, Bafile G, Di Cesare E, Alagia G, Ventura

M. Diagnostic imaging techniques in vascular graft infections. EurJ Vasc Endovasc Surg 1997;14(Suppl A):24–6.

9. Rossi P, Arata FM, Salvatori FM, et al. Prosthetic graft infection:diagnostic and therapeutic role of interventional radiology. J VascInterv Radiol 1997;8:271–7.

10. Liberatore M, Lurilli AP, Ponzo F, et al. Aortofemoral graftinfection: the usefulness of 99mTc-HMPAO-labelled scan. Eur JVasc Endovasc Surg 1997;14(Suppl A):27–9.

11. Debonnaire P, Van Rillaer O, Arts J, Ramboer K, Tubbax H, VanHootegem P. Primary aorto enteric fistula: report of 18 Belgian

cases and literature review. Acta Gastroenterol Belg 2008;71:250–8.