Case study

A 28 year old man presented to the accident and emergency department with central abdominal pain that had lasted just over a day and was “cramping” in nature. He had had bloody diarrhoea for three days, with increasing frequency and amount of blood. He had eaten a chicken sandwich purchased from a canteen the day before the onset of symptoms. There was no history of recent foreign travel or any important medical history.

On examination he was found to be warm and well perfused, and his abdomen was soft, with mild generalised tenderness. On admission his full blood count, renal function and liver function tests were all within normal range.

Three days after admission he had persistent bloody diarrhoea; his haemoglobin concentration had dropped by 40 g/l to 126 g/l. Colonoscopy and biopsies showed acute indeterminate colitis. His white cell count was 23.3×10⁹/l, neutrophils 19.1×10⁶/l, platelets 49×10⁹/l, international normalised ratio 1.0, APTT (activated partial thromboplastin time)1.0, C reactive protein 256 mg/l, urea 19.7 mmol/l, creatinine 530 µmol/l, potassium 4.8 mmol/l, serum lactate dehydrogenase 3452 U/l. He quickly became anuric.

Questions

• 1 What is the diagnosis?

• 2 What would you expect to find on culture of stool?

• 3 What would you expect to see on a blood film?

• 4 What is the differential diagnosis?

• 5 What two therapeutic procedures might this patient have?