Bacterial Pneumonia or Pulmonary Infarction?

¹ Associate Professor of Medicine and Director, Medical In-Patient Service, Ben Taub General Hospital

When the clinical problem is that of bacterial pneumonia vs pulmonary infarction, the best support for infection is shaking chills, purulent sputum, or bacteremia, whereas the best evidence of infarction is the angiographic demonstration of pulmonary thromboemboli. Important clues to infarction are a concurrent condition frequently predisposing to pulmonary thromboembolism; frankly bloody, nonpurulent sputum; sanguineous pleural effusion; migratory parenchymal infiltrates; and "pneumonia" unresponsive to chemotherapy. Such findings are inconstant, however, and it is unwise to consider them requisites for diagnosis. Moreover, one never should doubt or reject the possibility of pulmonary infarction simply because of high fever, leukocytosis, normal jugular venous pressure, "atypical" pulmonary lesions, nonbloody pleural effusion, failure to detect the source of the emboli, or because the patient is young or appears otherwise healthy.

Clinical defferentiation of bacterial pneumonia from pulmonary infarction occasionally is not possible. In that circumstance I recommend treatment for both disorders.