American Registry of Radiologic Technologists (ARRT) Practice Exam

What condition is characterized by pus in the thoracic cavity?

1. Pneumonia

2. Empyema

3. Pleural effusion

4. Tuberculosis

The correct answer is: Empyema

Empyema is characterized specifically by the accumulation of pus within the thoracic cavity, typically in the pleural space, which lies between the lungs and the chest wall. This condition often results from an infection, such as pneumonia, that leads to the production of pus and results in inflammation and infection of the pleura. The presence of pus indicates that there is a significant infectious process occurring, distinct from merely the presence of fluid as seen in other conditions. In the case of pneumonia, the infection could lead to empyema but does not itself refer to the accumulation of pus in the thoracic cavity. Pleural effusion refers to a buildup of fluid in the pleural space and can result from various causes, including heart failure or lung disease, but does not specifically denote pus. Tuberculosis, while it can affect the lungs and pleura, does not specifically indicate pus accumulation. Thus, the defining characteristic of empyema is the presence of pus, making it the correct answer in this context.