A 28-year-old woman with a history of asthma presented for evaluation of a recurrent pleural effusion following a motor vehicle accident in which she “rear-ended” a car. She was restrained by her shoulder and abdominal seat belt. Severe back and neck pain and refractory asthma developed over the next 2 weeks. CT of the chest ordered by her primary care physician revealed patchy nodular densities located around bronchovascular bundles and a pericardial effusion. A pericardial window and biopsy of the superior segment of the left lower lobe and pericardium showed histiocytic inflammation and chronic fibrous pericarditis, respectively. The pericardial fluid was chylous, with 5,500 nucleated cells with 68% lymphocytes; triglyceride level, 2,295 mg/dL; protein, 4.0 g/dL; and lactate dehydrogenase, 180 IU/L.