The Serum Amylase Test measures the amount of amylase, an enzyme that helps digest carbohydrates, in the blood. This enzyme is primarily produced by the pancreas and salivary glands.

Key Points:

• Purpose: The test is commonly used to diagnose or monitor conditions related to the pancreas, such as pancreatitis (inflammation of the pancreas), and sometimes for issues related to the salivary glands or abdominal pain.
• Normal Range: Typically, serum amylase levels are between 30 to 110 U/L (units per liter), though this can vary slightly by laboratory.
• Elevated Levels: High levels of amylase in the blood may indicate acute or chronic pancreatitis, pancreatic duct obstruction, gallbladder disease, or other abdominal conditions.
• Low Levels: Decreased amylase levels can be seen in chronic pancreatitis, liver disease, or cystic fibrosis.

The test is simple, requiring a blood sample, and results are usually available within a few hours to a day.

Pancreatitis, Pancreatic cancer, Liver disease

The amylase normal range in the blood is measured in units per litre (U/L). For an average adult- 30-115 units per litre (U/L) The normal value range may vary slightly among different laboratories. Several laboratories use different methods for the measurements.

High Serum Amylase Levels (Hyperamylasemia):

Common conditions associated with elevated amylase include:

1. Acute Pancreatitis:

   • Amylase levels can rise 3-6 times above normal within hours of an attack and usually peak within 12–72 hours.
   • Levels start to fall after a few days but can remain elevated for a week.

2. Chronic Pancreatitis:

   • Levels may rise during acute flare-ups, though not as high as in acute pancreatitis.

3. Pancreatic Pseudocyst:

   • Amylase levels may be elevated in people with pseudocysts resulting from chronic pancreatitis or trauma.

4. Other Causes of Elevated Amylase:

   • Gallbladder disease (cholecystitis, gallstones)
   • Gastrointestinal perforation (peptic ulcer)
   • Peritonitis
   • Renal failure (as amylase is excreted by the kidneys)
   • Macroamylasemia (amylase forms complexes with proteins in blood, reducing excretion)
   • Salivary gland inflammation or blockage (parotitis, mumps)
   • Some cancers (ovarian, lung, and pancreatic cancer)

Low Serum Amylase Levels (Hypoamylasemia):

Causes of low amylase levels may include:

1. Advanced Pancreatic Damage:

   • Chronic pancreatitis, late-stage pancreatic cancer, or cystic fibrosis may lead to reduced amylase production due to pancreatic insufficiency.

2. Liver Disease:

   • Liver diseases like cirrhosis can reduce amylase levels.

3. Kidney Disease:

   • If kidneys are unable to clear amylase from the blood effectively, this can sometimes present as decreased amylase levels in later-stage kidney disease.

4. Preeclampsia:

   • This pregnancy complication has been associated with decreased amylase levels.

Important Considerations:

• Timing of test: Amylase levels may not peak immediately after the onset of symptoms, so repeat testing is sometimes required.
• Other tests: Lipase is another pancreatic enzyme that is often tested alongside amylase for a more specific diagnosis of pancreatic disease, especially in acute pancreatitis where lipase remains elevated longer.

Specimen Details for Serum Amylase Test:

• Specimen Type: Blood (serum)
• Collection Method:
  • Blood is drawn from a vein, usually from the arm.
  • The blood is then processed to separate the serum, which is the liquid part of the blood after clotting.

Requirements:

• Volume: Typically, 3-5 mL of blood is collected.
• Container:
  • A standard red-top or serum separator tube (SST) is commonly used.
  • The SST contains a gel that separates the serum from the rest of the blood after centrifugation.

Pre-Test Considerations:

• Fasting: Fasting is generally not required, though the healthcare provider may offer specific instructions.
• Medications: Some medications may affect amylase levels (e.g., certain diuretics, opioids, and oral contraceptives), so it's important to inform the healthcare provider about all medications being taken.

Storage and Stability:

• Room Temperature: Serum should be tested within a few hours, or it should be refrigerated if it cannot be tested immediately.
• Refrigeration: The serum can typically be stored in the refrigerator for up to 48 hours.
• Freezing: If the sample needs to be stored longer, freezing is usually recommended.