On palpation, abdominal tenderness, voluntary guarding and involuntary abdominal rigidity, and rebound tenderness can be appreciated. Abdominal rigidity is typical and is referred as board like rigidity. This rigidity may be absent in elderly and immune-compromised patients. Hypovolemia (dry mucous membranes, tachycardia, hypotension), nausea fever and vomiting may co exist this initial phase of illness. | On palpation, abdominal tenderness, voluntary guarding and involuntary abdominal rigidity, and rebound tenderness can be appreciated. Abdominal rigidity is typical and is referred as board like rigidity. This rigidity may be absent in elderly and immune-compromised patients. Hypovolemia (dry mucous membranes, tachycardia, hypotension), nausea fever and vomiting may co exist this initial phase of illness. |