What does 'peritonitis' refer to in medical conditions?

Peritonitis refers specifically to the inflammation of the peritoneum, which is the thin tissue that lines the inner wall of the abdomen and covers the abdominal organs. This condition often arises due to infection, injury, or another underlying issue, and it can lead to severe complications if not addressed promptly.

Understanding the structure and function of the peritoneum is crucial. It serves not only as a protective layer but also plays a role in supporting the abdominal organs and facilitating movement. When inflammation occurs, it can cause significant abdominal pain, changes in bowel habits, and may lead to systemic illness due to infection.

In contrast, the other options describe inflammation of different organs. For instance, inflammation of the lungs pertains to respiratory issues, inflammation of the heart relates to cardiovascular diseases, and inflammation of the kidneys is often associated with renal problems. Each of these conditions involves separate anatomical structures and would present with different clinical signs and symptoms.