What is pneumonia an infection of?

Pneumonia is specifically defined as an infection that affects the lungs. It can be caused by a variety of pathogens, including bacteria, viruses, and fungi, and leads to inflammation of the lung tissue. This inflammation impairs gas exchange and can cause symptoms such as cough, fever, chest pain, and difficulty breathing. Understanding the anatomy and function of the lungs is vital in recognizing pneumonia, as treatment often focuses on alleviating the inflammatory response and addressing the underlying infection. The other organs listed—kidneys, liver, and gallbladder—are associated with different types of infections and illnesses, but are not involved in pneumonia.