QUESTION

A 19 year old female smoker was admitted with an eight week history of cramping lower abdominal pain, per rectal bleeding, weight loss, and loose stools. Past medical history included iritis and she was taking the oral contraceptive pill. There was a positive family history of Crohn’s disease (mother). Routine bloods revealed raised inflammatory markers, normal haemoglobin, and white cell count, but raised platelet count and fibrinogen levels. Stool culture was negative. The findings at colonoscopy were consistent, both macro- and microscopically, with Crohn’s colitis. She was commenced on intravenous fluids, oral asacol 800 mg three times daily, and prednisolone 40 mg daily. Her bloody diarrhoea started to settle within 48 hours.

She then developed sustained central visual loss in the left eye. Immediate ophthalmic review highlighted bilateral papilloedema, greater on the left than on the right, and signs of chronic uveitis.

What was the diagnosis made from the urgent magnetic resonance imaging brain scan requested in this patient?

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