Final Answer:
Purulent (Pus) pleural effusion is called empyema.
Step-by-step explanation:
Empyema refers to a type of pleural effusion characterized by the accumulation of pus in the pleural space, the cavity between the lungs and the chest wall. This condition usually arises as a complication of bacterial pneumonia, lung abscess, or chest trauma. Infections that reach the pleural space can trigger an inflammatory response, leading to the accumulation of purulent material, consisting of dead white blood cells, bacteria, and tissue debris. Empyema often presents with symptoms such as chest pain, fever, and difficulty breathing.
Diagnosis is typically confirmed through imaging studies, such as chest X-rays or CT scans, and treatment involves drainage of the infected fluid along with appropriate antibiotic therapy.