Fever and posterior mediastinal opacity following aorto-coronary bypass graft.

A4 62-year-old man was admitted with a four-week history of fever following an aorto-coronary bypass graft. The postoperative chest roentgenogram was normal. His past history included hypertension of 13 years' duration and coronary artery disease commencing three years previously. On examination, his tern-perature ranged between 37.5#{176} and 38.8#{176}C, a grade 2/6 apical systolic murmur was present, and a few rales were audible over the left lung base. Laboratory tests revealed an erythrocyte sedimentation rate (ESR) of 60 mm/i hr, hemoglobin ofii.8 g/dl, normal leukocyte count, serum LDH of 556 U/L (normal <320), and serum alkaline phosphatase of 125 U/L (normal <85). Other chemical values were normal. Blood cultures were negative for bacteria and fungi; virologic, rickett-sial and serologic studies were all negative. Serial electrocardiograms revealed a stable, diffuse ischemic pattern. A chest roentgenogram on admission (Fig 1) showed a small infiltrate with probable pleural effusion at the left costophrenic sinus and an infiltrate adjacent to the left cardiac border. A second roentgenogram (Fig 2) three days later revealed a large, round, well-demar-cated opacity situated in the posterior mediastinurn. The isotopic lung scan demonstrated a perfusion defect at the left base. The echocardiogram was normal.