Introduction: The development of a sero-sanguinous pleural effusion is a rare, often overlooked, manifestation of a ruptured infected aneurysm of the abdominal aorta.
Case report: A man of 84years was referred for management of a left-sided pleural effusion associated with symptoms of infection. He had presented two months previously with methicillin resistant staphylococcal septicaemia, the origin of which was a plantar ulcer. The patient was apyrexial and had no abdominal pain. A thoraco-abdominal CT scan without contrast showed a peri-aortic abdominal mass suggesting a tumour. A contrast enhanced scan and peri-aneurysmal aspiration showed that it was an infected aneurysm of the abdominal aorta that had ruptured into the left pleural cavity. The progress was unfavourable despite double antibiotic therapy.
Conclusion: In the face of a sero-sanguinous pleurisy, particularly if associated with unexplained symptoms of infection, a search should be made for an abdominal aortic aneurysm. Surgical treatment of the aneurysm should be undertaken if the general condition of the patient and the localisation and morphology of the aneurysm permit.