If a patient with acute pancreatitis shows symptoms of peritonitis, abdominal muscle rigidity may occur. Acute pancreatitis is divided into acute edematous pancreatitis and acute hemorrhagic necrotizing pancreatitis. The main symptoms of acute edematous pancreatitis include abdominal pain, nausea, vomiting, and fever. If it is hemorrhagic necrotizing pancreatitis, it can lead to shock, respiratory distress syndrome, high fever, jaundice, abdominal distension, and the abdominal compartment syndrome in the patient. Severe cases can cause intestinal paralysis and signs of peritoneal irritation, leading to abdominal muscle rigidity and also possibly presenting with shifting dullness, among other symptoms.