Pulmonary consolidation is a non-specific term for pulmonary opacities seen on radiography that are the result from a process that fills the alveolar spaces (further discussion here). The differential for the radiologic finding of pulmonary consolidation includes blood (pulmonary hemorrhage), pus (infection, i.e. pneumonia), fluid (heart failure), and cells (cancer).
In our patient with a pulmonary consolidation, the clinical findings of fever, cough and elevated WBC count raise infection (i.e. pneumonia) to the top of our differential. Every pulmonary lobe can be affected by pneumonia. Familiarity of bronchopulmonary anatomy is necessary for accurate interpretation of chest radiographs. An introduction to bronchopulmonary anatomy can be found here.
A few more cases of pediatric pneumonia can be seen in the next examples....