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an aortoesophageal fistula ( aef ) is a rare condition that is frequently fatal and requires emergency treatment .
the potential causes of aef include surgery , esophageal reflux , tuberculosis , trauma , corrosive esophagitis , aortic aneurysm , foreign body , or malignancy .
irrespective of the cause , the resulting massive upper gastrointestinal hemorrhage requires urgent treatment , such as surgery or embolization . in cases of aef ,
we report a case of aef with mediastinitis treated using a planned two - stage approach : an initial thoracic endovascular aortic repair ( tevar ) as a bridge to stabilization , followed by esophageal reconstruction surgery .
we believe that a two - stage approach is the optimal therapeutic option in certain aef cases .
a 52-yr - old man who experienced syncope after severe hematemesis was admitted to the emergency department on september 9 , 2012 .
chest computed tomography ( ct ) did not detect any aortic lesions , such as a thoracic aortic aneurysm , while an abscess - like lesion of the esophagus with blood leakage was detected ( fig .
1 ) . therefore , we performed endoscopy to obtain hemostasis of the upper gastrointestinal bleeding . at endoscopy
, the blood loss was found to be too severe to manage , and the patient was prepared for emergency surgery . as the patient 's vital signs were unstable ,
aortography confirmed the presence of a circular mass beside the esophagus at the t9 level .
a seal thoracic stent graft ( 30  100 mm , s&g biotech , seoul , korea ) was inserted at the t7 - 10 level , and subsequent aortography confirmed that no bleeding was present ( fig .
the patient was monitored for hematemesis in the intensive care unit for 12 hr after surgery .
as there was no hematemesis , the patient was transferred to a general ward and prepared for esophageal reconstruction . since concurrent inflammation of the mediastinum was very likely
after the white blood cell count and other inflammatory signs normalized , esophageal reconstruction was performed . after preparing for a gastric pull - up through a midline laparotomy ,
necrosis of the diverticulum was observed directly above the esophagogastric junction , which was found to contain thrombotic masses .
the esophagus was dissected until the point beneath the azygos vein ; after resection , an end - to - end anastomosis stapler ( 28 mm ) was used for the esophagogastrostomy . after confirming the location of the l - tube , a 28-fr chest tube was inserted , and the incision was closed . on pathological examination ,
the subserosal lymphoid tissue in the esophagus showed chronic granulomatous inflammation with caseous necrosis , and polymerase chain reaction analysis of tuberculosis was positive .
, this aef was considered to be a complication of tuberculous esophagitis and esophageal diverticulitis .
esophagography performed 7 days after the esophageal reconstruction showed a small esophageal anastomotic leak , and esophagogastroduodenoscopy ( egd ) was performed using dermabond to seal the anastomotic leak ( 1 ) .
the egd and esophagography were repeated 7 days later and confirmed the absence of anastomotic leakage .
subsequently , a soft diet was resumed and anti - tuberculosis treatment initiated ( fig .
the patient was discharged 20 days after the esophageal reconstruction and underwent anti - tuberculosis treatment for 9 months after the surgery .
based on the results of radiological examinations and a sputum acid - fast bacilli ( afb ) smear and culture , the patient was deemed to be cured of tuberculosis .
aortic ct and egd performed 1 and 2 yr postoperatively confirmed that the patient had recovered without any complications .
although aef is a rare disease , it requires urgent treatment and can be fatal . in most cases
, it involves an aortic aneurysm , and the classical treatment is aortic aneurysm surgery under cardiopulmonary bypass , followed by esophageal reconstruction or closing of the esophagus . however , mediastinitis is also seen in many cases , and the mortality rates associated with aortic aneurysm surgery performed under cardiopulmonary bypass are very high due to contamination of the surgical field ( 2 ) . in recent years , aortic stents have been used to treat such cases ( 34 ) . however , one report stated that the treatment of a thoracic aortic aneurysm using a stent graft can result in aef ( 5 ) .
moreover , in cases where mediastinitis is also seen , the infection can progress to recurrent aef . in our case , however , the aef was believed to have been caused by esophageal diverticulum inflammation rather than by an aortic aneurysm .
in addition , due to the severe hematemesis , the risk of cardiopulmonary bypass was considered to be high .
therefore , an emergency tevar was performed . after excluding the aef and before reconstructing the esophagus , the patient was administered preoperative antibiotic therapy to minimize the complications caused by mediastinal infection .
as there have been no reports on the duration of antibiotic treatment , we performed the reconstructive surgery once the white blood cell count , erythrocyte sedimentation rate , and c - reactive protein values were normalized , although this might not be sufficient .
the esophageal diverticulum was found to occupy half of the lower esophagus , as assessed by egd , and was accompanied by esophageal inflammation over a wide area ; consequently , primary repair was considered impossible .
the upper one - third of the esophagus appeared normal , while the middle and lower thirds showed severe adhesions , edematous changes , and esophageal swelling , although there were no gross signs of infection , such as pus . to ensure that the anastomosis was performed on the normal portion of the esophagus , the anastomosis was performed above the azygos vein .
the postoperative anastomotic leakage was believed to be due to the insertion of the aortic stent graft , which reduced the esophageal blood supply .
as the anastomotic leakage was the size of a pin point , an endoscopic intervention was considered to be better than a revision thoracotomy .
a large portion of aefs are located at the connection between a thoracic aortic aneurysm and the esophagus ; therefore , in such cases , using an aortic stent graft can reduce the risk of bleeding .
however , the fistula between the false lumen and esophagus remains intact and can potentially result in complications , such as graft infection .
one recent report described a patient with no prior aef who developed an aef after tevar ( 5 ) .
in general , tevar involves the use of a stent graft that is slightly larger in diameter than that of the aorta ; the resulting structural friction and reduced blood supply were believed to have caused the aef ( 6 ) .
after tevar , depending on the location of the aef , aortic replacement can be performed under cardiopulmonary bypass or under a temporary bypass connecting the left subclavian artery to the distal thoracic aorta .
the aef that occurs after tevar is very likely to be accompanied by an aortic stent graft infection ; therefore , the stent graft is removed , and extra - anatomical bypass or aortic replacement surgery is conducted ( 67 ) .
tuberculous esophageal disease does not arise primarily in the esophagus , but instead occurs by local extension from a nearby anatomical position ( 8) . compared with other locations in the gastrointestinal tract ,
if the esophagus and trachea are connected , liquid intake can lead to respiratory symptoms , such as coughing .
the systemic symptoms are accompanied by weight loss in many cases . as the symptoms alone can not be used to distinguish such cases from those of esophageal cancer ,
such complications due to tuberculous esophagitis can lead to the development of fistulas into the mediastinum ( 9 ) . in our case ,
however , when considering the long - term benefits , the use of tevar remains controversial , and many reports have been published on this subject ( 5 ) . in cases such as ours ,
when a state of shock is suspected due to sudden , severe hematemesis , tevar can stop the bleeding quickly and accurately .
we believe that this is an added value associated with the use of tevar as the primary treatment procedure , which is followed by planned secondary surgery .
case reports on secondary surgery of the aorta performed after tevar have also been published ( 10 ) . when an aef is caused by an aneurysm , open surgery might be better than tevar .
however , when an aef is caused by lesions in the esophagus , tevar is a good alternative .
an aortoesophageal fistula ( aef ) is an extremely rare , potentially fatal condition , and aortic surgery is usually performed together with extracorporeal circulation . 
 however , this surgical method has a high rate of surgical complications and mortality . 
 this report describes an aef caused by tuberculous esophagitis that was treated successfully using a two - stage operation . 
 a 52-yr - old man was admitted to the hospital with severe hematemesis and syncope . 
 based on the computed tomography and diagnostic endoscopic findings , he was diagnosed with an aef and initially underwent thoracic endovascular aortic repair . 
 esophageal reconstruction was performed after controlling the mediastinal inflammation . 
 the patient suffered postoperative anastomotic leakage , which was treated by an endoscopic procedure , and the patient was discharged without any further problems . 
 the patient received 9 months of anti - tuberculosis treatment after he was diagnosed with histologically confirmed tuberculous esophagitis ; subsequently , he was followed as an outpatient and has had no recurrence of the tuberculosis or any further issues .