Final answer:
Pus that accumulates in the lungs of a pneumonia patient is called empyema. It is a complication that involves the collection of pus in the pleural cavity, often resulting from a severe infection.
Step-by-step explanation:
Pus that accumulates deep within the lungs of a patient with pneumonia is called empyema. Pneumonia itself is an illness where the alveoli, the tiny sacs in the lungs for gas exchange, become inflamed and filled with fluid, leading to symptoms like cough, chest pain, fever, and difficulty breathing. The condition known as empyema involves the collection of pus in the pleural cavity due to infection and is often a complication of pneumonia.
This is different from an effusion, which is an accumulation of fluid in the pleural space without the presence of pus, or pleuritis, which is the inflammation of the pleura - the membrane surrounding the lungs. Fibrosis refers to the thickening and scarring of connective tissue, usually as a result of chronic inflammation or injury, including chronic infections like pneumonia. In the context of bacterial pneumonia, common causative agents include Streptococcus pneumoniae, H. influenzae, and Mycoplasma pneumoniae.