Gastroenterology Today Summer 2019

CASE REPORT
Examination revealed HR-95 b/m, BP 130/70 mm Hg, oxygen saturation
96% on 2 Litres of oxygen and normal temperature. Abdominal
examination revealed a large pulsatile abdominal mass. PR examination
revealed melaena on glove. She scored 10 points on the Glasgow-
Blatchford Bleeding Score.
After resuscitation with IV fluids and blood products the patient was
transferred to the ward. She had 3 further large episodes of melaena
on the same day and was taken to the endoscopy unit for upper GI
endoscopy which did not reveal blood in the upper GI tract, but did
show a deep ulcer in the second part of duodenum (D2) [Image 2&3].
Post- endoscopy Rockall Score was 6. The consultant who performed
the endoscopy was concerned about the morphology of the ulcer
and recommended a CT scan and urgent surgical review to rule out
a primary aorto-enteric fistula [PAEF]. In view of high suspicion of a
PAEF, the endoscopist elected not to perform endotherapy used for
bleeding duodenal ulcer. A 3 phase CT abdomen and pelvis revealed
an increase in size of the infrarenal abdominal aortic aneurysm [AAA]
which measured 8 cm [Image 4] (6.4cm previously [Image 1]). New
gas locules within the inferior aspect of aneurysm sac were highly
suggestive of aorto-enteric fistulation. The aortic sac was inseparable
from the proximal duodenum and tracking gas locules were suggestive
of a communication between aneurysm sac and second part of
duodenum [Image 4]. An urgent vascular review was requested and
vascular surgeons decided not to surgically intervene as the patient
was very frail and unlikely to survive a repair. This was discussed with
the patient and her daughter and decision for palliation was made. The
patient had another massive haematemesis and melaena early in the
morning of the next day and died after a few hours.
Discussion
Formation of fistula between aorta and intestinal tract was first described
by an English Surgeon Sir Ashley Cooper in 1829 [1]. But the first case
report of PAEF was published by Salmon in 1843. Since then only about
400 of PAEF cases have been reported up until now [2&3]. PAEF is a
potentially fatal and a rare complication of untreated aortic aneurysm,
which warrants a high index of clinical suspicion when presented with
upper GI haemorrhage. The fistula most commonly erodes into an
area of intestine (most commonly the third part of duodenum) which
has close contact with the pulsating aortic segment [4, 5&6]
The classical triad of symptoms with abdominal pain, pulsatile
abdominal mass and gastrointestinal haemorrhage are only found
in 6-12% of patients [7&8]. The most common presentation is upper
GI haemorrhage. Often the initial GI bleeding is small (herald bleed),
but one third of the patients presents with massive recurrent bleeding
within 6 hours [9]. Many patients with aorto-enteric fistula (AEF) die
before an accurate diagnosis is made due to its variable clinical
manifestations and insufficient awareness of this rare entity among
non-specialty clinicians. Although literature review suggests the most
common aetiology for PAEF are atherosclerotic and traumatic AAA,
other causes include radiation, cancer, metastasis, gallstone erosion,
ulcers, diverticulitis appendicitis, aortitis, infections like TB, pancreatic
pseudo cyst penetration and foreign body ingestion[10&3].
Unusual features of this case include the fistulous connection between
the AAA and second part of duodenum and the presence of a deep
ulcer on endoscopy. Even though no literature is available to confirm,
it is possible that standard endotherapy for bleeding duodenal ulcer
(adrenaline injection, heater probe, gold probe coagulation and
endoclip placement) may lead to massive haemorrhage in patients
with aorto-enteric fistula. In our patient, possibility of PAEF was
considered very high and endotherapy was not attempted.
Though less frequent, there are reports in literature that described
abnormal communication between aorta and other pat of GI tract such
as the oesophagus, jejunum, ileum and colon, but most of these were
secondary to endovascular or other surgical procedures on aorta
causing secondary fistulation [11].
GASTROENTEROLOGY TODAY - SUMMER 2019
Image [2] A-Endoscopic view of deep ulcer in D2
Image [3] A-Endoscopic view of deep ulcer in D2
Image 2
8
Image 3