Hyperamylasemia

Background

• Amylase is secreted by the pancreas into the duodenum where it aids the catabolism of carbohydrates to simple sugars
• Damage to the pancreas or obstruction to the pancreatic duct causes the enzyme to enter the bloodstream.

Clinical Features

• Pain in the middle of the chest that radiates to the back
• Fever
• Loss of appetite
• Nausea
• Vomiting
• Sweating
• Weakness
• Jaundice
• Rapid pulse
• Steatorrhea

Differential Diagnosis

• Pancreatic:
  • Acute pancreatitis
  • Chronic pancreatitis (can have normal or mildly elevated levels)
  • Pancreatic pseudocyst
  • Pancreatic duct obstruction
  • Pancreatic trauma or neoplasm
• Non-Pancreatic:
  • Salivary gland disease (e.g., parotitis)
  • Perforated peptic ulcer
  • Bowel obstruction or infarction
  • Cholecystitis
  • Ectopic pregnancy
  • Ruptured aortic aneurysm
  • Macroamylasemia
  • Renal failure (impaired clearance)

Evaluation

Workup

• Serum amylase and lipase (lipase is more specific for pancreatitis)
• CBC, CMP (assess electrolytes, renal function, LFTs)
• Liver enzymes, bilirubin, alkaline phosphatase
• CRP (to assess inflammation)
• Abdominal ultrasound (to evaluate gallstones, ductal dilation)
• CT abdomen with contrast (gold standard if pancreatitis is suspected)
• Pregnancy test in females of childbearing age
• Urinalysis (to evaluate renal excretion and exclude other causes)

Diagnosis

• Hyperamylasemia is typically defined as serum amylase >100 U/dL, although labs may vary by reference range.
• Levels >3x normal are suggestive of acute pancreatitis when correlated with clinical presentation.
• Isolated hyperamylasemia without supportive clinical features does not confirm pancreatitis and warrants evaluation for alternative causes.

Management

• Acute pancreatitis:
  • NPO, IV fluids, electrolyte repletion
  • Pain control (e.g., IV opioids)
  • Monitor for complications (e.g., necrosis, sepsis, pseudocyst)
  • Antibiotics only if infected necrosis is suspected
• Non-pancreatic causes:
  • Tailored to condition (e.g., surgery for perforation, supportive care for parotitis)
• Macroamylasemia:
  • Benign; no treatment needed
• Address underlying conditions contributing to pancreatic ischemia (e.g., hypotension, trauma)

Disposition

Admit if:

• Suspected or confirmed acute pancreatitis
• Ongoing abdominal pain, vomiting, or systemic toxicity
• Need for IV hydration, monitoring, or further imaging
• Evidence of complications (e.g., pseudocyst, cholangitis, organ dysfunction)

Discharge may be appropriate if:

• Mild, incidental hyperamylasemia without systemic signs
• Identified non-critical cause (e.g., resolved salivary gland infection)
• Reliable outpatient follow-up available

See Also

Acute Pancreatitis

Abdominal Pain