What is the term for inflammation of the membrane lining the abdominal cavity?

The term for inflammation of the membrane lining the abdominal cavity is peritonitis. This condition is the result of irritation or infection of the peritoneum, which is the serous membrane that forms the lining of the abdominal cavity, covering the abdominal organs. Peritonitis can arise from various causes such as bacterial infection, perforation of abdominal organs, or complications from certain medical conditions. Recognizing peritonitis is essential, as it often requires prompt medical attention due to its potential severity and complications.

Mesenteritis refers specifically to inflammation of the mesentery, which is the fold of tissue that attaches the intestines to the posterior abdominal wall, and is distinct from inflammation of the peritoneum. Appendicitis is the inflammation of the appendix, commonly presenting with abdominal pain and requiring surgical intervention. Colitis denotes inflammation of the colon, which can result from various causes including infection, inflammatory bowel disease, or ischemia. Understanding these distinctions highlights why peritonitis is the correct answer, as it specifically pertains to the inflammation of the abdominal cavity lining.