History: 40 year old man with 1 week history of productive cough and fevers.
This is a classic case of lobar pneumonia, which is most commonly bacterial in origin.
Hospital acquired pneumonia is commonly caused by: Staphylococcus Aureus, anaerobes, and gram negative organisms.
Community acquired pneumonia is commonly caused by: Pneumococcus, mycoplasma, viruses, and not commonly legionella or klebsiella.
If the lung consolidation doesn’t improve in 6-8 weeks, the concern is heightened for an obstructing lesion in the bronchus, such as bronchioalveolar cell carcinoma.
Read about the differential diagnosis for lung masses.
Read about the differential diagnosis for a solitary pulmonary nodule.