What term describes the inflammation of the membrane that lines the abdominal cavity?

The term that describes the inflammation of the membrane lining the abdominal cavity is peritonitis. The peritoneum is a thin layer of tissue that covers the abdominal wall and the organs within the abdomen. When this membrane becomes inflamed, it can lead to a variety of symptoms, including abdominal pain, tenderness, and possibly fever, reflecting the body's immune response to the underlying cause, which could be infection, injury, or a disease process.

Peritonitis can be a serious condition, as it may result from infections such as those caused by bacteria entering the abdomen through wounds or perforations in the gastrointestinal tract. It may also arise from complications of diseases such as appendicitis or diverticulitis. Thus, recognizing the role of the peritoneum and the effects of its inflammation is crucial in diagnosing and treating abdominal illnesses.

The other terms mentioned describe inflammation in different contexts: vasculitis refers to inflammation of blood vessels, serositis denotes inflammation of serous membranes but is broader than just the peritoneum, and pericarditis focuses specifically on inflammation of the pericardial sac surrounding the heart. These distinctions reinforce why peritonitis is the correct term for the inflammation of the abdominal cavity lining.