Mediastinal Abscess Caused by an Expanded Polytetrafluoroethylene Membrane

A 76-year-old man who had undergone tricuspid annuloplasty 13 years earlier was admitted to our hospital because of a high fever. Although he was treated with antibiotics for pneumonia, a mild fever persisted. Computed tomography and gallium scintigraphy revealed a mediastinal abscess with an expanded polytetrafluoroethylene (ePTFE) membrane. There were no positive cultures or sternal changes indicating poststernotomy mediastinitis. The membrane was removed by a left parasternal approach without resternotomy, and its total removal was essential for the patient's recovery. This is the first reported case of sterile mediastinal abscess caused by an ePTFE membrane after a cardiac operation.