What are the other Names for this Test? (Equivalent Terms)
- Urine Amylase Test
- Serum Amylase Test
- Peritoneal Fluid Amylase Test
What is Amylase Test? (Background Information)
- Amylase is an enzyme (a protein causing a specific chemical change), which is secreted mainly from the pancreas and salivary glands of the body
- It helps in breaking-down complex carbohydrates and starches into simple sugars, to aid in digestion and absorption of sugars into the body. This is important, because simple sugars are ultimately converted to glucose, which fuels all of the body's processes
- Amylase levels may increase in blood, urine, and sometimes in the peritoneal fluid, during pancreatic disease
- An Amylase Test is performed to measure the level of amylase in blood, urine, or peritoneal fluid (fluid collected in the area of the abdomen, called the peritoneal space)
- The test is used to diagnose or monitor acute pancreatitis (inflammation of the pancreas). It may also be performed for chronic pancreatitis, pancreatic pseudocyst, and also to help detect digestive tract problems
What are the Clinical Indications for performing the Amylase Test?
Following are the clinical indicators for performing an Amylase Test:
- A healthcare provider may order the test, often along with a lipase test, if there is:
- A suspicion of a pancreatic problem, including pancreatitis, gallstones
- A blockage of the duct that carries amylase and other substances from the pancreas to the small intestine, for digestion of carbohydrates and starches present in food
- The symptoms of a pancreatic disorder may include:
- Severe abdominal or back pain
- Loss of appetite
- Nausea and vomiting
- To monitor patients with cystic fibrosis, a genetic condition in which thick mucus blocks passages in the lungs and digestive system, causing repeated lung infections and problems with absorbing nutrients. In cystic fibrosis, when mucus blocks the pancreatic ducts from carrying the enzymes that the small intestine needs to digest food properly, blood levels of amylase rise
- The Amylase Test may also be ordered to monitor the effectiveness of treatment for pancreatitis and other pancreatic diseases
- The blood test for amylase may be ordered along with the urine amylase levels for better evaluation of pancreatic damage
- Amylase levels may also increase during mumps (inflammation of the salivary gland), trauma to salivary glands, or renal failure (due to reduced amylase clearance from the kidneys)
How is the Specimen Collected for Amylase Test?
Following is the specimen collection process for Amylase Test:
Sample required: Blood, peritoneal fluid, 24-hour or 2-hour urine sample
- Procedure for collecting blood sample: Insertion of needle into a vein (arm)
- Procedure for collecting peritoneal fluid: Insertion of needle through the skin of abdomen into the peritoneal space, for a sample of the peritoneal fluid. This process is called paracentesis. The area is cleaned with an antiseptic and numbed, prior to needle insertion
Procedure for collecting 24-hour urine sample:
- The first urine sample, after waking up in the morning, is discarded. The time is noted down, and this marks the beginning of a 24-hour collection period
- All urine, over the next 24-hour period is collected in a large container (normally supplied by the healthcare provider)
- Do not contaminate the large container. Use a small container to collect urine, each time. Transfer this into the large container
- Use ice to keep the container at very low temperature (else refrigerate the container and contents)
- Just before the end of the 24-hour collection period, empty the bladder one last time, to collect the final urine sample
- Keep the 24-hour urine sample free of any contaminants or foreign matter, like toilet paper, stool, menstrual blood, pubic hair, etc.
Procedure for collecting 2-hour urine sample:
- The first urine sample, after waking up in the morning, is discarded. The time is noted down, and this marks the beginning of a 2-hour collection period
- All urine, over the next 2-hour period is collected in a large container (normally supplied by the healthcare provider)
- Care has to be taken to not contaminate the large container. A smaller container is used to collect urine, each time. This is then transferred to the larger container
- Use ice to keep the container at very low temperature (else refrigerate the container and its contents)
- Just before the end of the 2-hour collection period, empty the bladder one last time, to collect the final urine sample
- Keep the 2-hour urine sample free of any contaminants or foreign matter, like toilet paper, stool, menstrual blood, pubic hair, etc.
A 2-hour urine sample is collected for a period of 2 hours, in the same manner as the 24-hour urine collection.
- No special preparation is needed prior to the test
- However, some drugs may interfere with the test result. The healthcare provider must be informed about all the drugs you are currently taking
- Intake of alcohol should be avoided before the test
What is the Significance of the Amylase Test Result?
Small amounts of amylase are normally present in blood. However, increased amounts (up to 4-6 times higher levels) may be released into blood, when the pancreas is injured, inflamed, or blocked.
Increased blood amylase levels may indicate:
- Infections of the salivary glands or a blockage
- Acute pancreatitis: Elevated amylase levels follow the pattern of increase of lipase concentrations. In acute pancreatitis, lipase levels take longer to rise than amylase levels. The amylase levels begin to fall after a while; lipase levels remain elevated for a longer period of time. Hence, both levels should be tested
- Chronic pancreatitis
- Cancer of the pancreas, ovaries, or lungs
- Gastroenteritis (severe)
- Intestinal blockage
- Macroamylasemia: A harmless condition in which amylase is bound to protein in blood, causing higher levels
- Pancreatic or bile duct blockage
- Perforated ulcer in stomach or duodenum
- Tubal pregnancy (abnormal location of pregnancy in fallopian tubes, which is also called ectopic pregnancy)
Decreased blood amylase levels may indicate:
- Cancer of the pancreas
- Damage to the pancreatic tissue
- Kidney disease
- Toxemia of pregnancy
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- In chronic pancreatitis, amylase levels are initially increased. With progressive pancreatic damage, the levels often decrease over time. Hence, chronic pancreatitis amylase levels may be increased, decreased, or at normal levels
- Chronic pancreatitis is often associated with alcoholism. It is seen in association with cystic fibrosis and may be caused by trauma, or pancreatic duct obstruction
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider, the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.