What do peritoneal signs indicate?

Peritoneal signs are clinical indicators that suggest the presence of irritation or inflammation of the peritoneum, which is the serous membrane lining the abdominal cavity. These signs typically include abdominal tenderness, rigidity, guarding, or rebound tenderness when pressure is applied to the abdomen.

When evaluating the options, peritoneal signs are most commonly associated with peritonitis, which is the inflammation of the peritoneum usually caused by infection or other irritants. This condition can result from various intra-abdominal issues such as a perforated organ, resulting in significant abdominal distress and requiring immediate medical attention.

In contrast, while appendicitis, cholecystitis, and gastritis can present with abdominal pain and may have some overlapping symptoms, they do not specifically indicate irritation of the peritoneum. Appendicitis might lead to peritoneal signs if there is perforation, but the peritoneal signs themselves are a direct indication of peritonitis, making option B the correct choice.