Which sign indicates peritoneal irritation in appendicitis?

• A. Rebound tenderness
• B. Murphy's sign
• C. Cullen's sign
• D. Grey Turner's sign

Answer: (A)

Peritoneal irritation manifests as rebound tenderness. When you press on the abdomen and then release, if the pain is greater upon letting go, it signals irritation of the peritoneum by inflammation, such as in appendicitis. The inflamed peritoneum is highly sensitive, so the sudden decompression triggers a sharp pain. In appendicitis, the inflamed appendix irritates the surrounding peritoneum, making rebound tenderness a classic sign.

Other signs point to different problems: Murphy’s sign is associated with gallbladder disease and causes inspiratory arrest when the RUQ is palpated; Cullen’s sign and Grey Turner's sign are bruising around the umbilicus or in the flank, indicating intra-abdominal or retroperitoneal bleeding rather than peritoneal irritation from appendicitis.