3. Discussion:
UC is a type of inflammatory bowel disease that causes inflammation and
ulcers in the colon and rectum. It is associated with several
extra-intestinal manifestations including arthritis, uveitis, erythema
nodosum, pyoderma gangrenosum, primary sclerosing cholangitis among
several other conditions(4). Patients with inflammatory bowel disease
are at an increased risk for both venous and arterial thromboembolism.
This risk appears to be increased in patients with pan-colonic disease
and those with ulcerative colitis. Hypercoagulable states associated
with UC, are often serious, recurrent, tend to occur at unusual sites
(e.g., cerebral vein), are associated with active disease, and occur in
younger individuals. CVT is a rare but severe complication of UC. Most
commonly, the superior sagittal and lateral sinuses are involved(2).
Furthermore, it has been associated with the use of steroids, possibly
indicating an active underlying disease. Our patient was a young female
(in her 30s), who had ulcerative colitis flare despite steroids and
azathioprine therapy.
What increases the chances of hypercoagulation in UC is not known. Data
suggests that it is multifactorial and includes elevated levels of
factors V, VIII, fibrinogen, total homocysteine, and decreased levels of
antithrombin III as well as platelet disorders. Thrombocytosis and
leukocytosis are common(5). Assessment of coagulation factors,
homocysteine, and antithrombin III could not be done in our patient due
to unaffordability and was unlikely to alter our treatment plan.
She was started on early anticoagulation with heparin. The European
guidelines recommend treating acute CVT with heparin at a therapeutic
dosage even in patients with intracerebral hemorrhage at baseline
followed by oral anticoagulants for 3-12 months(6). With bridging
anticoagulation, our patient recovered fully or her symptom was
improved. She was commenced on oral dabigatran on discharge. This is the
standard practice unless there is a contraindication to anticoagulation
such as active bleeding. Her risk factors for coagulopathy included her
positive family history of stroke in her mother and her diagnosis of UC.
Her flare of ulcerative colitis increased the risk of thromboembolism.
For patients with acute severe UC who fail to respond to steroids and
immunosuppressant, surgery is indicated(7). Total proctocolectomy often
cures the patient of Ulcerative colitis. However, case has been reported
in a patient who developed CVT 10 years after total proctocolectomy(8).
This case also highlights the importance of regular follow-up in such a
patient to monitor the disease activity. Our patient had missed several
appointments due to COVID pandemic.
Furthermore, thalamic infarction following CVT is rare and is sparsely
reported in the literature. It may be either arterial or venous in
origin. Occlusion of the artery of Percheron is responsible for arterial
ischemia whereas venous infarction may be caused by thrombosis of the
straight sinus, where the posterior group of thalamic veins drains. This
is due to upstream venous pressure. Our patient had thrombosis of the
straight sinus and was responsible for bilateral thalamic infarction. It
is important to differentiate between these two as arterial occlusion
requires immediate thrombolysis, whereas venous occlusion requires
anticoagulation(9).
4. Conclusion:
Cerebral sinus vein thrombosis is a rare but often fatal complication of
ulcerative colitis if undiagnosed. Cerebral venous sinus thrombosis may
rarely cause bilateral thalamic infarction. Patients with ulcerative
colitis should follow up with their regular physician to track activity
of the disease.