Primary aorto-duodenal fistula following Staphylococcal septicaemia.

A 73-year-old lady presented to the emergency department with a 6 h history of haematemesis, abdominal pain and back pain. On examination she was haemodynamically stable and abdominal examination revealed a non-tender abdominal aortic aneurysm (AAA). Haemoglobin was 7 g/dl. Eleven weeks previously she had undergone a coronary angiogram, followed 2 days later by an angioplasty and stent insertion. Because of a suspected coronary artery dissection the femoral sheath was left in situ for 24 h as a precaution. She was discharged well 3 days later. She returned 1 day after discharge with a staphylococcal septicaemia, which resolved with antibiotic treatment. During this admission she had several episodes of melaena. Upper GI endoscopy demonstrated a gastric ulcer and abdominal ultrasound revealed a 3.4 cm abdominal aortic aneurysm. Emergency contrast CT scan demonstrated an aorto-duodenal fistula with peri-aortic inflammation (Fig. 1). At endoscopy no abnormality was found in the stomach or duodenum. At laparotomy a 4 cm AAA, adherent to the third part of the duodenum was found. The distal small bowel was full of blood. The proximal aorta and iliac vessels were normal. Following infra-renal aortic cross clamping the duodenum was dissected off the aorta. A 1 £ 1 cm defect in the aorta plugged by thrombus and connected to the third part of the duodenum was found. The aorta was repaired with an in situ bifurcated rifampicin-soaked graft, the duodenal defect was closed with 3/0 polyglyconate and an omental flap was interposed between repairs. A specimen of aortic tissue and an aortic swab were cultured and grew Staphylococcus aureus sensitive to flucloxacillin. The patient was treated with the appropriate intravenous antibiotics postoperatively. A peri-graft collection developed in the second post-operative week (Fig. 2). Aspirate from this collection grew Pseudomonas. This resolved on double anti-pseudomonal therapy. The patient remained in hospital for 9 weeks for intravenous antibiotic therapy. Serial CT scans and measurement of inflammatory markers confirmed resolution of infection and she was discharged well. Follow-up CT scan at 5 months demonstrated complete radiographic resolution (Fig. 3).