Acute pancreatitis usually announces itself with pain and vomiting, but its examination findings depend on how severe the attack is. Diagnosing an episode from the history and physical examination alone is not easy, because it can resemble several acute illnesses of the abdomen, such as biliary colic.
Pain occurs in more than 95% of cases. It is moderate to severe and usually felt in the upper abdomen, most often across the whole upper part or in the epigastric or right upper quadrant regions, with a band-like distribution to the back; pain confined to the left side of the upper abdomen is rare. It is occasionally felt in the lower abdomen, when pancreatic exudate reaches the left colon. The pain reaches its highest intensity 10–20 minutes after the initiation of the attack, and pain that is intermittent and stops after a period of time is suggestive of other conditions, such as biliary colic. Nausea and vomiting occur in more than 90% of patients.
The findings on examination depend completely on the severity of the attack. On inspection, a patient with a moderate attack does not appear acutely ill, while a patient with a severe attack does. Abdominal distension is the most important parameter to judge; it is more prominent in severe attacks and in the epigastric region, where pancreatic exudate can lead to gastric, colonic or intestinal ileus. Ecchymosis of the abdominal wall appears in less than 1% of cases, in severe conditions with a bad prognosis: flank ecchymosis (Grey Turner sign) and peri-umbilical ecchymosis (Cullen sign). Severely ill patients can show tachypnoea with shallow breathing, because sub-diaphragmatic pancreatic exudate makes movement of the diaphragm painful, and because of pleural effusion.
Palpation carries much of the differential diagnosis. The parameters to consider are abdominal tenderness, abdominal guarding — the involuntary contraction of the abdominal wall musculature in response to palpation, often due to underlying inflammation of the peritoneum — and abdominal rigidity, which is more common in diffuse peritonitis. In a mild attack, abdominal tenderness is mild and guarding may be absent. On auscultation, intestinal movements are reduced or can stop.
The other findings that can be seen in an attack of acute pancreatitis are fever; a blood pressure that may first increase and then fall with shock; a raised heart rate in most patients; encephalopathy; oliguria; conjunctival icterus in patients with gallstone-related disease; electrolyte imbalances; panniculitis — inflammation of subcutaneous fat tissue with necrosis and a surrounding erythematous region, mostly on the extremities; hepatomegaly; and spider angiomata.