Acute pancreatitis (AP) is a sudden inflammation of the pancreas. Causes in order of frequency include: 1) a gallstone impacted in the common bile duct beyond the point where the pancreatic duct joins it; 2) heavy alcohol use; 3) systemic disease; 4) trauma; 5) and, in minors, mumps. Acute pancreatitis may be a single event; it may be recurrent; or it may progress to chronic pancreatitis. Mild cases are usually successfully treated with conservative measures: hospitalization, pain control, nothing by mouth, intravenous nutritional support, and intravenous fluid rehydration. Severe cases often require admission to an intensive care unit to monitor and manage complications of the disease. Complications are associated with a high mortality, even with optimal management. Signs and symptoms
Common
severe epigastric pain (upper abdominal pain) radiating to the back in 50% of cases
nausea
vomiting
loss of appetite
fever
chills (shivering)
hemodynamic instability, including shock
tachycardia (rapid heartbeat)
respiratory distress
peritonitis
hiccupAlthough these are common symptoms, frequently they are not all present; and epigastric pain may be the only symptom.
Blood investigations – complete blood count, kidney function tests, liver function, serum calcium, serum amylase and lipase
Imaging – A triple phase abdominal CT and abdominal ultrasound are together considered the gold standard for the evaluation of acute pancreatitis. Other modalities including the abdominal x-ray lack sensitivity and are not recommended. An important caveat is that imaging during the first 12 hours may be falsely reassuring as the inflammatory and necrotic process usually requires 48 hours to fully manifest. Differential diagnosis
The differential diagnosis includes:
Perforated peptic ulcer
Biliary colic
Acute cholecystitis
Pneumonia
Pleuritic pain
Myocardial infarction

Biochemical
Elevated serum amylase and lipase levels, in combination with severe abdominal pain, often trigger the initial diagnosis of acute pancreatitis. However, they have no role in assessing disease severity. Serum lipase rises 4 to 8 hours from the onset of symptoms and normalizes within 7 to 14 days after treatment. Serum amylase may be normal (in 10% of cases) for cases of acute or chronic pancreatitis (depleted acinar cell mass) and hypertriglyceridemia. Reasons for false positive elevated serum amylase include salivary gland disease (elevated salivary amylase), bowel obstruction, infarction, cholecystitis, and a perforated ulcer. If the lipase level is about 2.5 to 3 times that of amylase, it is an indication of pancreatitis due to alcohol.Decreased serum calcium
GlycosuriaRegarding selection on these tests, two practice guidelines state:

"It is usually not necessary to measure both serum amylase and lipase. Serum lipase may be preferable because it remains normal in some nonpancreatic conditions that increase serum amylase including macroamylasemia, parotitis, and some carcinomas.