Acute pancreatitis is rare during pregnancy. The reported incidence varies from 1/1000 to 1/4000 pregnancies.1
The most common etiologies of pancreatitis include gallstone disease and alcohol abuse.2 During pregnancy, symptomatic gallstone disease is the leading cause. Other less common causes include hypercalcemia, hypertriglyceridemia, trauma, ischemia, pancreatic tumors leading to pancreatic duct obstruction, and medications, such as thiazides and azathioprine. An association between acute pancreatitis and preeclampsia has been described.3 The mechanism for the latter is unclear but may be related to severe vasoconstriction with resultant pancreatic ischemia.
Close to 20% of cases are considered to be idiopathic; many of these cases likely have a genetic predisposition.4
The pathophysiology of acute pancreatitis relates to local activation of pancreatic enzymes (eg, trypsinogen to trypsin), leading to pancreatic tissue injury with a massive inflammatory response that may result in severe vasodilation, increased vascular permeability with third spacing, and multiorgan failure.
Pancreatitis should be suspected in patients presenting with constant epigastric pain associated with nausea and vomiting. The pain typically radiates to the back and precedes nausea and vomiting. The intensity of the pain is usually severe. The diagnosis during pregnancy may be more challenging, as some of the symptoms may be associated with physiological changes of pregnancy. During the second half of pregnancy, such presentation always warrants a workup for preeclampsia.
Serum amylase and lipase are the most commonly used laboratory parameters. Amylase usually rises within hours of the event and returns to normal values in 3 to 5 days.5 Amylase is nonspecific and may also be elevated in multiple extrapancreatic conditions, such as salivary gland disease, appendicitis, cholecystitis, renal injury, peptic ulcer disease, and bowel pathology. Serum lipase is more specific than amylase and remains elevated for longer periods of time. Despite the increased specificity, lipase may also be elevated in renal injury and extrapancreatic abdominal pathology, such as appendicitis and cholecystitis.6 Imaging studies are rarely necessary to establish the diagnosis, as the diagnosis in most cases is easily made with the clinical presentation coupled with elevated lipase values. Pancreatic imaging may be indicated in cases where the diagnosis is unclear or when there is failure to improve within 2 to 3 days after presentation. Contrast-enhanced computed tomography might be used; during pregnancy, the use of magnetic resonance may be more appropriate (no ionizing radiation exposure), as it may diagnose pancreatic necrosis even without the use of gadolinium.7
All patients with acute pancreatitis should undergo an abdominal ultrasound to identify gallstone disease as the etiology. In cases of a normal ultrasound and no history of alcohol abuse, a serum triglyceride level should be obtained and considered the cause of pancreatitis if more than 1000 mg/dL.8
Once the diagnosis is established, the clinician should attempt to classify the disease as mild ...