Bilateral internal carotid artery occlusion (BICAO) although rare, is associated with 0-13% annual stroke rate. Recent studies demonstrate that inflammatory bowel disease (IBD) patients have 14% greater odds of premature (age at diagnosis ≤ 55 years) and 82% higher odds of extremely premature (age at diagnosis ≤ 40 years) atherosclerotic cardiovascular disease. Studies on patients with symptomatic BICAO demonstrate high risk of recurrent stroke despite maximal medical treatment, therefore surgical revascularization is recommended.

A forty-year-old, non-smoker, lacto-vegetarian male with controlled hypertension, uncontrolled diabetes, and six recent attacks of TIA treated with risk factors modification, presented with right sided weakness and aphasia. Head CT showed acute left frontal lobe ischemic stroke. Head and neck CT angiogram showed occlusion of left anterior cerebral artery, high grade near-occlusive stenosis of bilateral internal carotid arteries (ICAs) more on left side, left ICA intraluminal thrombus, and atherosclerosis with moderate narrowing of bilateral distal vertebral arteries. The diagnostic work-up demonstrated hemoglobin A1c 10, LDL 58, B12 513, normal TSH and folic acid. Echocardiogram, telemetry, and venous duplex showed no significant findings. Patient surpassed TPA window and was not endovascular candidate. Treatment included heparin drip for left ICA thrombus followed by left ICA endarterectomy. Recurrent abdominal distension and watery stools warranted CT abdomen that showed proctosigmoiditis. High fecal calprotectin (510) confirmed IBD diagnosis.

Extensive atherosclerosis in young patient with limited traditional vascular risk factors suggested possible vitamin B12 deficiency with resultant hyperhomocysteinemia. Although patient was lacto-vegetarian, B12 was normal, confounding the diagnosis. Confirmation of IBD provided a clue for the premature atherosclerosis. Treatment included medical optimization of vascular risk factors and the underlying inflammatory disease. Failure of previous medical therapy warranted surgical revascularization. Our case highlights IBD as a risk factor for premature extensive atherosclerosis of internal carotid arteries.