Abstract | | |
Background: Fistulous tracts within the thorax are best exemplified aorto-esophageal fistulas (AEFs), which are rare exsanguinations of the upper gastrointestinal tract. Most of them are diagnosed at autopsy. Aim: This is an autopsy-based study of fatal cases of AEFs gathered over a period of 20 years. Materials and Methods: Cases of AEFs were retrieved from the autopsy records of the cardiovascular pathology sub-specialty at a tertiary care center and were studied with reference to demographic details, modes of clinical presentation, and pathological features. Results: Ten cases of AEFs (10 males and 8 females, mean age of 46.9 years) were identified in a span of 20 years. A clinical diagnosis of AEF was made in only one patient, while the rest were identified at autopsy. All the patients had a bout of massive and fatal hematemesis. The fistulous connections, involving the middle-third of the esophagus, were caused by a fishbone, esophageal ulceration and aneurismal aortic diseases of varied etiology. Conclusions: AEFs are often missed or misdiagnosed. Early recognition of this rapidly fatal condition is essential as these fistulas require quick and aggressive management.
Keywords: Aortic aneurysms, aorto-esophageal fistula, fistula, thorax
How to cite this article: Vaideeswar P. Aorto-esophageal fistula – An autopsy series. Indian J Pathol Microbiol 2020;63:597-9 |
Introduction | |  |
A fistula is an abnormal communication between the lumen and the surface of one organ with another. It can occur in any part of the body and at any age; some are even congenital. The skin and the gastrointestinal tract are the commonest sites for such fistulous connections. Such fistulous tracts within the thorax are rare and are best exemplified by aorto-esophageal fistulas (AEFs), which are rare exsanguinations of the upper gastrointestinal tract.[1] Since they are very often fatal, most of them are diagnosed at autopsy. This is a report of such fistulas gathered over a period of 20 years.
Materials and Methods | |  |
We reviewed the autopsy records of the cardiovascular pathology sub-specialty at our center over a span of 20 years for the presence of AEFs, which included esophageal communications with the aorta or its branches. The demographic details and modes of clinical presentation were retrieved from the hospital records. All the specimens had been fixed in 10% buffered formalin. The specimens were carefully scrutinized for the identification of the fistulous tracts and then dissected further. The hearts were cut along the flow of blood, and the aortic segments along their greater curvatures. After detailed gross examination, relevant sections were taken. They were embedded in paraffin, sectioned at 5 μm, and stained with hematoxylin and eosin. Special stains were performed as per the requirements.
Results | |  |
Ten cases of AEFs [Table 1] were identified in a span of 20 years. A diagnosis of AEF was rendered in one patient after a computed tomographic scan (Case 3), while the condition was not clinically detected in the remaining patients. There were eight males and two females with an age range of 15 to 70 years (mean age of 46.9 years). All the patients had a bout of massive hematemesis leading to death, one of which had occurred in the post-operative period (Case 8). However, five patients also had episodic hematemesis for a period of one day to one month. In one young patient [Case 1, [Figure 1], a fishbone in the esophagus had pierced a normal descending thoracic aorta, while in another elderly patient (Case 2), the connection was between an esophageal ulcer and an aberrant retro-esophageal right subclavian artery. In the remaining eight patients, the fistulas were due to aneurismal aortic disease caused by complicated atherosclerosis [Figure 2], syphilitic aortitis, Takaysau's disease, and tuberculous aortitis. The additional aorto-bronchial fistula was found in one patient. The middle third of the esophagus was involved in all the cases. Esophagoscopy had been performed in five patients and diagnosis of esophageal carcinoma was made in three patients. | Figure 1: A fishbone (arrow) protrudes into the descending thoracic aorta DTA and had produced a 0.7 cm transverse ragged opening
Click here to view |
 | Figure 2: (a) An arrow points to the mouth of a saccular aneurysm An seen in the proximal part of the descending thoracic aorta DTA; (b) The aneurysm has produced a bulge in the esophagus E with an irregular, circular ulceration (arrow); (c) Transverse section through the fistula between the aneurysm An in the proximal descending thoracic aorta P-DTA and the esophagus E (arrows); (d) The aneurysm was atherosclerotic in nature (H and × 250); (e) The asterisk shows the junction between the ulceration and the epithelial lining (H and E × 250) [LCCA left common carotid artery, LSA left subclavian artery, RBCA right brachiocephalic artery]
Click here to view |
Discussion | |  |
We have reported 10 autopsied cases of AEF, which is a life-threatening condition demanding an emergent intervention. It is, fortunately, a rare phenomenon with an incidence of 0.001 to 0.08%.[1] The most common causes of these fistulous connections are thoracic aortic aneurysms, ingested foreign bodies, and esophageal cancers; rarer causes include esophageal ulceration, gastroesophageal reflux disease, corrosive ingestion, trauma, and tuberculosis. All these causative factors lead to primary AEF (as seen in all our cases), while those related to aortic or esophageal interventions or surgery constitute the category of secondary AEF.[2] In this series too, the fistulas occurred expectedly due to atherosclerotic aortic disease but only in three cases; while in the remaining five other patients, they had been related to aortitis. The aortitis in all these patients had produced aneurysms. Tuberculosis can lead to TEFs due to the involvement of the mediastinal lymph nodes, which then lead to the affection of the esophagus and/or the aorta,[3] the latter was seen in one of our cases (Case 7). Takayasu arteritis is a rare cause, but the surprising finding was syphilitic aortitis, which still can be identified sporadically at autopsy.[4] Ulceration and subsequent perforation lead to fistulous with a non-aneurysmal aberrant right subclavian artery and till recently only about 18 cases have been reported so far.[5] Both the esophagus and the aorta were normal in an adolescent where a fishbone produced the AEF.[6]
The symptomatology of AEF is said to be characterized by mid-thoracic chest pain and a 'signal' or 'sentinel' hemorrhage followed by massive hemorrhage after a window period or lucid interval of few hours to few days. This is referred to as Chiari's triad, which seldom occurs in all patients[1] and was seen in two (20%) of our patients; rest had symptoms related to the underlying aortic disease. Esophagoscopy, which is usually the first mode of diagnosis, was performed in five patients. Unfortunately, connection was obscured by blood clots in two patients or simulated malignant ulcerative growth in three other patients, thereby leading to a missed diagnosis or misdiagnosis.[7] Early recognition of this rapidly fatal condition (preferably in the window period) by an optimal imaging modality (such as computed tomography performed in Case 3) is essential as these fistulas require quick and aggressive management in the form of surgery or endovascular stenting.[8]
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References | |  |
1. | Hollander JE, Quick G. Aortoesophageal fistula: A comprehensive review of the literature. Am J Med 1991;91:279-87. |
2. | Gupta R, Mittal P, Mittal G. Aorto-esophageal fistula secondary to penetrating atherosclerotic ulcer. J Emerg Trauma Shock 2012;5:262-4.  [ PUBMED] [Full text] |
3. | Panda SS, Agarwala S, Kabra SK, Ray R, Sugandhi N, Bhat AS, et al. Aortoesophageal fistula in a child. J Indian Assoc Pediatr Surg 2013;18:124-6.  [ PUBMED] [Full text] |
4. | Vaideeswar P. Syphilitic aortitis: Rearing of the ugly head. Indian J Pathol Microbiol 2010;53:624-7.  [ PUBMED] [Full text] |
5. | Shires CB, Rohrer MJ. Anomalous right subclavian artery-esophageal fistulae. Case Rep Vasc Med 2018;2018:7541904. |
6. | Kelly SL, Peters P, Smithers BM. Successful management of aortoesophageal fistula caused by a fish bone – Case report and review of literature. J Cardiothorac Surg 2009;4:21. |
7. | Yang Y, Hu D, Peng D. Primary aortoesophageal fistula: A fatal outcome. Am J Emerg Med 2018;36:343. |
8. | Marone EM, Coppi G, Kahlberg A, Tshomba Y, Chiesa R. Combined endovascular and surgical treatment of primary aortoesophageal fistula. Tex Heart Inst J 2010;37:722-4. |

Correspondence Address: Pradeep Vaideeswar Department of Pathology (Cardiovascular and Thoracic Division), Seth GS Medical College, Parel, Mumbai - 400 012, Maharashtra India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/IJPM.IJPM_26_20

[Figure 1], [Figure 2]
[Table 1] |