Amylase is an enzyme that helps digest carbohydrates by breaking down starches into sugars. It is primarily produced in the salivary glands and pancreas and plays a critical role in the digestive process. Amylase levels can be measured in blood or urine to assess various medical conditions, particularly those affecting the pancreas.

Why is Amylase Tested?

1. Diagnosing Pancreatic Disorders:

• Acute pancreatitis: Amylase levels often rise significantly during an acute inflammation of the pancreas.
• Chronic pancreatitis: May show moderately elevated or even normal amylase levels if the pancreas is severely damaged.
• Pancreatic cancer: Elevated levels can occur but are less specific.

1. Detecting Salivary Gland Issues:

• Elevated amylase levels can indicate parotitis (inflammation of the salivary glands), such as in mumps.

1. Investigating Abdominal Pain:

• Amylase is tested to rule out pancreatic involvement as a cause of pain.

1. Assessing Other Conditions:

• Perforated ulcers, intestinal obstruction, or ectopic pregnancy can sometimes elevate amylase due to secondary effects on the pancreas.

Normal Amylase Levels

• Blood Amylase: 30–110 U/L (units per liter), though ranges may vary between laboratories.
• Urine Amylase: Typically less than 500 U/24 hours.

Causes of Elevated Amylase

1. Pancreatic Causes:

• Acute pancreatitis: Levels can increase 3–5 times the upper normal limit within hours of onset and normalize in 3–5 days.
• Chronic pancreatitis: Mild or moderate increases during flare-ups.

1. Salivary Gland Causes:

• Mumps (parotitis): Infection of the salivary glands.
• Blockage or inflammation of salivary ducts.

1. Other Causes:

• Gallbladder disease: Such as gallstones causing secondary pancreatic inflammation.
• Intestinal conditions: Perforation, obstruction, or ischemia.
• Renal failure: Reduced clearance of amylase.
• Ectopic pregnancy or ruptured cysts: Rarely.

Causes of Low Amylase

• Severe pancreatic damage: In chronic pancreatitis or late-stage pancreatic cancer, the pancreas may no longer produce enough amylase.
• Cystic fibrosis: Associated with reduced pancreatic enzyme production.
• Removal of the pancreas (pancreatectomy).

Interpreting Results

• Elevated Amylase: Suggests pancreatic or salivary gland involvement but is not specific to a particular condition.
• Low Amylase: May indicate chronic conditions where the pancreas no longer functions effectively.

Limitations of the Test

• Amylase is not entirely specific to the pancreas; elevated levels can occur in other conditions affecting the abdomen or salivary glands.
• Lipase, another pancreatic enzyme, is often measured alongside amylase for better specificity in diagnosing pancreatitis.

Symptoms Leading to Amylase Testing

1. Acute pancreatitis:

• Severe upper abdominal pain radiating to the back.
• Nausea, vomiting, or fever.

1. Chronic pancreatitis:

• Recurring abdominal pain.
• Malabsorption symptoms like weight loss or diarrhea.

1. Mumps or Parotitis:

• Swelling and tenderness of the salivary glands.
• Difficulty swallowing or fever.