Pneumonia in the context of severe sepsis: a significant diagnostic problem.

showed multiple ill-defined increased densities in both lower lung fields. High-resolution computed tomography was then performed and showed ill-defined, wedge-shaped increased densities with patent airways in the posterior subpleural regions of both lower lobes. The computed tomography differential diagnosis was organising pneumonia, bronchopneumonia, Churg–Strauss syndrome, Wegener granulomatosis, pulmonary haemorrhage, or vasculitis of various causes. Transbronchial lung biopsy was performed in the right lower lobe. Microscopic examination showed alveolar haemorrhage without evidence of vasculitis, eosinophilic infiltration or organising pneumonia. Serum circulating antiphospholipid antibodies were eventually found. Therefore, pulmonary angiography was performed and an intra-arterial low density was found in the right main pulmonary artery. This finding was believed to be compatible with pulmonary thromboembolism; however, it didn’t exclude a possible right pulmonary artery sarcoma. In this case, the only procedure that would rule out the presence of a right pulmonary artery sarcoma (without delays in diagnosis) with any reasonable certainty was surgery.