Listeria monocytogenes: A rare cause of mycotic aortic aneurysm

A 73-year-old man presented with pain in both iliac fossae radiating to the lumbar regions. He was a known hypertensive with a past history of myocardial infarction. Eight weeks before admission he had a chest infection treated successfully by his family practitioner. On examination he was pyrexial with a mid-abdominal pulsatile mass. Aneurysmal dilatation of his aorta was confirmed on ultrasound. His white blood-cell count on admission was 12,700 mm super(3) with 85 per cent neutrophils, 14 per cent lymphocytes and 1 per cent monocytes.