Case presentation:
A 40-year-old lady, presented to the hospital with 1-week history of
generalized abdominal pain, moderate to severe in intensity, associated
with nausea and 4 episodes of vomiting, with no aggravating or relieving
factors. There was no history of fever, hematemesis, bleeding per
rectum, chest pain or palpitations. Patient was a known case of
hypothyroidism, vitiligo, and type 1 diabetes mellitus. She was a
non-smoker. Patient had no personal or family history of thrombophilia
and there was no history of recurrent abortions. Physical examination
revealed an afebrile patient, with heart rate of 92 beats per minute,
blood pressure 124/76 and respiratory rate 17 breaths per minute.
Abdominal examination showed diffuse tenderness, no organomegaly, normal
percussion note with normal bowel sounds. Cardiac, respiratory and
nervous system examination as normal.
Labs investigations showed mild neutrophilic leukocytosis, high
C-reactive proteins, microcytic anemia, normal urea, creatinine,
electrolytes and liver function tests (table 1). Coagulation testsing
showed normal PT, aPTT and INR (Table 2).
A computed tomography (CT) scan of abdomen with contrast showed diffuse
thickening of the splenic flexure, descending colon and sigmoid colon
with surrounding mesenteric oedema and fat stranding as well as a
thrombus in the abdominal aorta at the level of L3 vertebra (Figure
1,2). However, all the thrombophilia screen and autoimmune work up was
negative (Table 3).
Patient was managed as a case of ischemic colitis due to spontaneous
abdominal aorta thrombosis. She was started on anticoagulation with
warfarin bridged by therapeutic dose enoxaparin with a target INR of
2-3. A follow up CT-Scan of abdomen that was done 2 months afterwards
showed resolution of thrombus and improvement of the inflammatory
changes in the bowel (Figure 3). Three months afterward, she presented
with left sided abdominal pain, nausea and vomiting. CT scan of the
abdomen was done, and it showed Focal segmental circumferential mural
thickening of the distal descending colon as a complication of the
ischemic colitis the patient was admitted and underwent left
hemicolectomy. She was then discharged home after improvement.
Discussion:Spontaneous arterial thrombosis is rare in occurrence, but It has a
significant clinical importance as it leads to several complications’
secondary to blood flow impediment (3). It can involve any organ system
with the resulting ischemia and/or infarction. Prompt diagnosis and
management is always needed as any delay can cause acute complications
which can include renal infarction, stroke, abdominal and peripheral
ischemia with gangrene, and might eventually lead to death. Presentation
depends on the system or the organ involved (3). Clinically significant
thrombosis can be because of a primary hypercoagulable state or as
secondary to trauma, immobilization or other coagulopathic
abnormalities. Suspicion should arise towards an underlying abnormality
whenever a patient has history of unprovoked arterial or venous
occlusion. Evaluation for causes such as factor V Leiden, antithrombin
III deficiency or protein C or S deficiency is warranted in unprovoked
cases (4).
Spontaneous abdominal aorta thrombosis is rare as the blood flowing in
the aorta has a high velocity which, along with high caliber of the
artery, makes it less prone to thrombosis and it is almost always
secondary to an underlying hypercoagulable status. (5) It can present
with manifestations that could range from asymptomatic in cases of
chronic thrombosis to a more severe one in patients with acute
thrombosis which can lead to devastating results with hemodynamic
instability and even peripheral or abdominal organ loss. (6) As the
abdominal aorta is the major source of arterial supply, its involvement
can lead to renal artery ischemia with renal infarction, colonic
ischemia, and limbs ischemia. Diagnosis should always be prompt. Initial
evaluation should start with basic laboratories such as CBC, which can
show increased white cell count, increased lactate denoting ischemia,
acute kidney injury or liver injury. Urgent imaging evaluation should be
done next. CT scan with contrast is usually the imaging diagnostic of
choice as it can reveal the thrombus and allow prompt diagnosis of any
underlying complication. CT scan can also help in excluding other
diagnoses. (7) A full and thorough evaluation for possible underlying
hypercoagulability must be sought. Treatment should be pursued as soon
as possible, and it usually depends on the presentation and hemodynamic
stability. Usually, the approach in stable patients with an established
thrombus is to start on anticoagulation with warfarin and bridging
enoxaparin (8). There is currently limited date at present on the novel
anticoagulants use in hereditary thrombophilia’s and in spontaneous
aorta thrombosis. The duration of anticoagulation is usually guided by
the underlying cause, as some patients require life-long anticoagulation
for prophylaxis (9).