Aorto-enteric fistulas: a physiopathological approach and computed tomography diagnosis

Primary and secondary aortoenteric fistulas in a patient with abdominal aortic aneurysm

INTRODUCTION

Aortoenteric fistulas (AEF) are infrequent malignant complications of abdominal aortic aneurysms (AAA). We present a unique case of a patient with recurring AAA fistulisations.

PRESENTATION OF CASE

During oncologic treatment, a 63-year-old male was incidentally diagnosed with infrarenal AAA and assigned follow-up but was hospitalised with anaemia and elevated inflammation markers 14 months later. A CT-angiography scan detected an AAA enlargement, but no extravasation (negative FOBT). Another CTA-scan displayed a pseudoaneurysm and ruptured AAA 10 days later. During a total laparotomy, an enlarged pulsating inflammatory conglomerate without active leakage was detected, with a 2 cm duodenal defect (PAEF). The AAA was resected and replaced by a linear silver-coated Dacron graft. 3,5 years after PAEF, the patient was hospitalised with abdominal pain and haematemesis. He underwent gastroscopies, coloscopies, CT- and CTA-scans - all without significant findings. Only after the capsule-endoscopy detected a jejunal ulcer, the PET-scan visualized active regions in the jejunum and the aortic graft. A total laparotomy was performed; previous stapler-lined jejuno-jejunal anastomosis had adhered to the silver-coated Dacron graft (SAEF). The Dacron graft was removed and replaced with a linear xenograft from bovine pericardium.

DISCUSSION

No evidence-based recommendations prefer endovascular aneurysm repair (EVAR) over open repair, leaving the strategy dependent on local preferences. Whether EVAR or initial xenograft usage would have shown surpassing results, is speculative, as no graft material/type has proved long-term pre-eminence.

CONCLUSIONS

This case displays AEF's complex treatment and challenging diagnosis. Multimodal diagnostic and strategic approaches should be considered for best patient outcome.

Mycotic Aneurysm with Iliac Artery-Colonic Fistula

Although mycotic (infected) aneurysms are uncommon, they can affect any artery. The most frequently involved vessel is the aorta as well as femoral and cerebral arteries. A vascular-colonic fistula from infected aneurysms is even rarer, which remains a challenge for diagnosis and treatment. In this case report, we aimed to illustrate an 89-year-old man presenting initially with an aneurysm of the right common iliac artery. Forty days later, this lesion was infected and produced fresh blood in the rectum and sigmoid colon observed by colonoscopy. The final diagnosis of this case was a right common iliac artery aneurysm-colonic fistula due to infection. The patient was successfully diagnosed and treated with surgery at our hospital.

Intraoperative endoprosthesis customization for repair of an aortoenteric fistula in an emergency context: a case report

Aortoenteric fistula is a severe clinical condition and its management remains a major technical challenge for surgeons. In these cases, the conventional surgical approach is associated with high rates of morbidity and mortality. Endovascular surgery is an excellent option in these cases, but considering that the aorta has been treated previously, anatomy may not be compatible with commercially available endovascular devices and so physician-modified endografts may be needed in urgent cases. The case reported involves a secondary aortoenteric fistula, treated on an emergency basis with endovascular techniques, using a physician-modified endograft.

Aortic Fistulas: Pathophysiologic Features, Imaging Findings, and Diagnostic Pitfalls

Fistulas between the aorta and surrounding organs are extremely rare but can be fatal if they are not identified and treated promptly. Most of these fistulas are associated with a history of trauma or vascular intervention. However, spontaneous aortic fistulas (AoFs) can develop in patients with weakened vasculature, which can be due to advanced atherosclerotic disease, collagen-vascular disease, vasculitides, and/or hematogenous infections. The clinical features of AoFs are often nonspecific, with patients presenting with bleeding manifestations, back or abdominal pain, fever, and shock. Confirmation with invasive endoscopy is often impractical in the acute setting. Imaging plays an important role in the management of AoFs, and multiphasic multidetector CT angiography is the initial imaging examination of choice. Obvious signs of AoF include intravenous contrast material extravasation into the fistulizing hollow organ, tract visualization, and aortic graft migration into the adjacent structure. However, nonspecific indirect signs such as loss of fat planes and ectopic foci of gas are seen more commonly. These indirect signs can be confused with other entities such as infection and postoperative changes. Management may involve complex and staged surgical procedures, depending on the patient's clinical status, site of the fistula, presence of infection, and anticipated tissue friability. As endovascular interventions become more common, radiologists will need to have a high index of suspicion for this entity in patients who have a history of aneurysms, vascular repair, or trauma and present with bleeding. Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. ^©RSNA, 2021.

Primary aortogastric fistula following Nissen fundoplication: A case report

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Aortogastric fistula is rare however often fatal.

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Diagnosis is frequently missed or delayed, and usually made intra-operatively or during autopsy.

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High index of suspicion and CTA are key to diagnosis.

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Endoscopy and catheter angiography are often non diagnostic.

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Surgical repair is the gold standard therapy, but endovascular repair is becoming the preferred initial treatment.

Introduction

Aortoenteric fistula (AEF) is a rare condition and consists of an abnormal communication between the aorta and the gastrointestinal (GI) tract. The duodenum is the most common location. Fistulas involving the stomach are very uncommon and account for only 2% of the cases. AEF typically results in rapid and fatal exsanguination as diagnosis is frequently missed or made too late (Bixby et al., 2018; Kougias et al., 2003; Lookman, 1959; Genc et al., 2000; Ong et al., 2019; Li et al., 2020).

Presentation of case

A 59 years old female with a history of Nissen fundoplication presented with lower gastrointestinal bleeding. Esophagogastroduodenoscopy (EGD) showed a large blood clot in the gastric fundus with no visible source of active bleeding. A mesenteric angiogram, performed for persistent gastro-intestinal bleeding and following two episodes of cardiac arrest, showed no evidence of active bleeding. The left gastric artery was prophylactically embolized. Persistent hemorrhage prompted an exploratory laparotomy followed by a left thoracotomy and confirmed the diagnosis of an aortogastric fistula (AGF). The patient expired intra-operatively.

Discussion

AGF is a very rare but often fatal condition (Busuttil and Goldstone, 2001). Computerized tomography angiography (CTA) can be a key to the diagnosis (Raman et al., 2012). EGD and catheter angiography have low sensitivity (Kuhara et al., 2015; Manduch et al., 2008). Definitive diagnosis is usually made during surgical exploration or autopsy (Wasvary et al., 1997). While open surgical repair is considered the gold standard therapy, endovascular therapy is becoming the preferred initial treatment option (Bixby et al., 2018).

Conclusion

AGF should be considered in the differential diagnosis of GI bleeding, especially in patients with massive hemorrhage where EGD and mesenteric angiography are not diagnostic.

Two cases of recurrent uterine cervical cancer with arterio-enteric fistula treated by femoro-femoral artery bypass in hybrid operation room

Little has been reported regarding aortic-enteric fistula (AEF) as a complication of gynecologic cancers because of its rarity. However, since it is lethal if left untreated, medical practitioners involved with gynecologic diseases should be aware of this deadly condition. In our hospital, we encountered two cases of cervical cancer complicated by AEF. In both cases, contrast computed tomography (CT) revealed leakage of the contrast material from an artery into the small intestine, indicating AEF. Endovascular procedures with complete embolization of the affected arteries and femoro-femoral artery bypass (f-f bypass) were performed in the hybrid operation room. The activities of daily living improved dramatically for both patients, and they survived for 3 months before dying from cervical cancer. While embolization by endovascular methods and f-f bypass performed in a hybrid operation room is, therefore, an available option for treating AEF, literature is lacking and more research is required to improve long-term outcomes for this disease.

ACR Appropriateness Criteria® Nonvariceal Upper Gastrointestinal Bleeding

Upper gastrointestinal bleeding (UGIB) remains a significant cause of morbidity and mortality with mortality rates as high as 14%. This document addresses the indications for imaging UGIB that is nonvariceal and unrelated to portal hypertension. The four variants are derived with respect to upper endoscopy. For the first three, it is presumed that upper endoscopy has been performed, with three potential initial outcomes: endoscopy reveals arterial bleeding source, endoscopy confirms UGIB without a clear source, and negative endoscopy. The fourth variant, "postsurgical and traumatic causes of UGIB; endoscopy contraindicated" is considered separately because upper endoscopy is not performed. When endoscopy identifies the presence and location of bleeding but bleeding cannot be controlled endoscopically, catheter-based arteriography with treatment is an appropriate next study. CT angiography (CTA) is comparable with angiography as a diagnostic next step. If endoscopy demonstrates a bleed but the endoscopist cannot identify the bleeding source, angiography or CTA can be typically performed and both are considered appropriate. In the event of an obscure UGIB, angiography and CTA have been shown to be equivalent in identifying the bleeding source; CT enterography may be an alternative to CTA to find an intermittent bleeding source. In the postoperative or traumatic setting when endoscopy is contraindicated, primary angiography, CTA, and CT with intravenous contrast are considered appropriate. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Graft Infection Masquerading as Rheumatologic Disease: a Rare Case of Aortobifemoral Graft Infection Presenting as Hypertrophic Osteoarthropathy

BACKGROUND

Prosthetic vascular graft procedures are a common treatment modality for peripheral vascular disease. A relatively common complication is graft infection, occurring at a rate of 0.5-5%. When they occur, graft infections are associated with significant morbidity and mortality. Vascular graft infections also represent a diagnostic and therapeutic challenge for the physician METHODS: Here, we report a case where the rare finding of secondary hypertrophic osteoarthropathy was an important indication of underlying aortic graft infection that was initially misdiagnosed. A review of the literature revealed 34 cases of vascular graft infection associated with hypertrophic osteoarthropathy.

RESULTS

The mean interval from surgery to time of infection was approximately 5 years. Mortality was 35%. When combined with hypertrophic osteoarthropathy, vascular graft infection was complicated by an aortoenteric fistula in 53% of the cases.

CONCLUSION

The complexity of this case highlights the challenges physicians face in order to diagnose and treat this condition.

Aorto-enteric Fistula 15 Years After Uncomplicated Endovascular Aortic Repair with Unforeseen Onset of Endocarditis

Introduction

Aorto-enteric fistula after endovascular aortic repair is an exceedingly rare but serious condition.

Report

A rare case of a fistula between the excluded aortic sac and the transverse colon 15 years after endovascular aortic repair is described. Onset was endocarditis without gastrointestinal haemorrhage, migration, endoleak, or aortic sac dilatation. The patient was successfully treated by fistula excision, debridement and broad spectrum antibiotic treatment without endograft explantation.

Discussion

Aorto-enteric fistula can emerge after endovascular repair with an unforeseen onset such as endocarditis, which in this case probably occurred as metastatic sepsis from endograft infection.

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Uneventful endovascular aneurysm repair can generate an aorto-enteric fistula to a successful excluded and stable aneurysm sac.

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This case underlines the need for awareness of unusual symptoms that could represent potential late EVAR related complications.

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A conservative approach without graft removal seems feasible in this case with severe comorbidity.

MDCT of endoleaks following endovascular repair of abdominal aortic aneurysms

Endovascular aneurysm repair has been used to repair abdominal aortic aneurysms but necessitates surveillance to diagnose the delayed possibility of endoleak formation. Multi-detector computer tomography (MDCT) of the abdomen is one imaging technique used to diagnose enlargement of the aneurysm sac that may be indicative of endoleaks. MDCT has a role in identifying the initial endoleak formation and providing signs suggestive of the specific endoleak subtype; thus it is necessary for radiologists to be familiar with the findings of endoleak seen on MDCT. In this pictorial review, we explore the various types of endoleaks and their appearance on MDCT.