Hyperamylasemia

What is Hyperamylasemia?

Hyperamylasemia is the term used when the level of amylase in your blood is higher than normal (usually between 30 U/L to 110 U/L). Amylase is one of the enzymes that helps digest food in our bodies. Its job is to break down starches, a type of carbohydrate, into smaller sugars. This process happens through a chemical reaction called hydrolysis, which ends up releasing sugars like maltose and other small carbohydrates.

Amylase is mostly produced in the pancreas and the salivary glands. About 40-45% comes from the pancreas and 55-60% from the salivary glands. There are two types of amylase: P-type, which comes from the pancreas, and S-type, from the salivary glands. The body gets rid of amylase through the kidneys (25%) and a system in the body called the reticuloendothelial system (75%).

It’s important to note that while checking amylase levels is often part of the process, it is not the best test for diagnosing a condition called pancreatitis, an inflammation of the pancreas. This is because it does not always clearly point to pancreatitis. While amylase levels may be higher in about 75% of pancreatitis cases, sometimes they may also fall within the normal range even when the pancreas has severe damage.

What Causes Hyperamylasemia?

Hyperamylasemia is a condition where there is too much amylase in the blood. This can be due to issues with the pancreas, salivary glands, or other health problems.

Let’s start with problems related to the pancreas. Acute pancreatitis can occur where severe abdominal pain appears along with high levels of serum amylase, which is above three times the normal limit. After an initial attack of pancreatitis, if the high amylase level persists for longer than expected, around three to seven days, it may indicate the disease is recurring.

Additionally, trauma such as an injury, surgery, or a procedure known as endoscopic retrograde cholangiopancreatography (ERCP) on the pancreas, can cause the amylase enzyme to be released from the pancreatic cells. Other reasons related to the pancreas may include chronic pancreatitis, pancreatic pseudocysts (fluid-filled sacs), pancreatic ascites (fluid build-up), pancreatic trauma, and obstructive gallstone disease.

Moving on to the salivary glands, increased blood amylase can be caused by several factors such as injury to the salivary gland, neck radiation involving the parotid gland, or blockage of the salivary gland with stones.

Rarely, conditions that disrupt the body’s natural ability to get rid of amylase, such as kidney or liver failure, can also lead to Hyperamylasemia.

Other situations that can lead to high amylase levels in the blood include macroamylasemia (a benign condition involving a large form of amylase complex in the blood), diseases of the small intestine, complications from certain female reproductive disorders, cancers such as lung, ovary, pancreas cancer, certain hormonal conditions, blood conditions like multiple myeloma, and conditions that lead to too much acid in the body, and even a type of procedure known as balloon-assisted enteroscopy.

Risk Factors and Frequency for Hyperamylasemia

Doctors frequently test for amylase levels in patients who they think might have acute pancreatitis. However, although this test is sensitive, it isn’t always accurate. In a study of 1000 emergency department patients with stomach pain, only about 4% were diagnosed with pancreatitis, even though 39% were tested for amylase. It’s also worth noting that 11% to 13% of patients with stomach pain not related to pancreatitis still show increased pancreatic enzymes. Also, raised amylase levels are common after heart surgery, affecting between 30% to 60% of patients.

When examining serum amylase levels, it’s important to take a person’s age and racial or ethnic group into account, as these can affect the results. For instance, research indicates that 32% of Asian Americans and 50% of Native Americans have amylase levels higher than the normal limit compared to white people. Additionally, older people, both men and women, tend to have higher total serum amylase because as we age, our kidneys may become less efficient at removing it from our bodies.

Signs and Symptoms of Hyperamylasemia

Hyperamylasemia, a condition where the blood has high levels of amylase, can happen because of many different factors. For this reason, doctors have to investigate the patient’s medical history carefully to figure out the root cause. A very sharp increase in amylase, more than three times the upper normal limit, along with sudden severe stomach pain and touch sensitivity, could suggest acute pancreatitis ailment.

Sometimes, a blockage in the parotid duct could be the culprit, especially if the patient complained of pain in the parotid gland (salivary gland in the cheek area), and if there’s a previous record of sialolithiasis – a condition where stones are formed in the salivary gland. This same gland can be inflamed due to mycobacterium, a type of bacteria, often resulting in long-lasting symptoms of parotitis, an infection of the salivary gland.

In rare cases, exposure to certain harmful substances, like organophosphates, could lead to hyperamylasemia. Such substances can cause salivary gland inflammation, which in turn can lead to elevated amylase levels in the blood.

Other potential factors that doctors consider include whether the patient recently had ERCP (a procedure to examine the pancreatic and bile ducts), any physical injury or a surgery. In children, doctors would check if the kid has received all the necessary vaccines, for conditions such as mumps for instance. Also, the doctor would look into other health conditions like alcohol misuse, inflammatory bowel disorder, kidney failure, liver illness, or a family history of pancreatitis.

Testing for Hyperamylasemia

A blood test that measures the level of a substance called “serum amylase” is often used to help identify a condition known as acute pancreatitis. This condition happens when your pancreas becomes inflamed and causes severe pain in your upper belly area. If your doctor can duplicate this pain by pressing on your stomach and your amylase level is three times higher than normal, they may diagnose you with acute pancreatitis without using any imaging scans.

Another substance, called “serum lipase”, can also be checked through a blood test. However, ordering both tests—amylase and lipase—does not necessarily provide a clearer diagnosis. If the amylase level is higher than normal but not three times the limit, and you have belly pain, your doctor could order a computed tomography (CT) scan. This imaging test uses x-rays and a computer to create detailed pictures of your pancreas.

Besides these tests, your doctor might want to get more detailed information from other laboratory tests. These might include a complete blood count, basic metabolic panel, tests for liver function (alanine aminotransferase or ALT, aspartate aminotransferase or AST), calcium, albumin, and bilirubin levels.

Magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatogram (MRCP) could also be used. Both of these tests use powerful magnets and radiowaves to produce images and can provide additional details about the condition of your pancreas.

If your doctors perform a procedure called ERCP (where they examine your bile and pancreatic ducts using an endoscope, a type of camera), they might also measure amylase levels post-procedure. This is because, if the amylase level is more than five times the normal limit six hours after this procedure, it accurately predicts any inflammation in the pancreas that might occur post-procedure.

In cases where only the amylase level is high but there are no other symptoms, a condition called “macroamylasemia” should be considered. This tends to happen when the body is dealing with inflammation due to conditions like celiac disease and rheumatoid arthritis.

Macroamylasemia is diagnosed using the so-called amylase-to-creatinine clearance ratio (ACCR). This ratio would be less than 1 in macroamylasemia due to inefficient kidney filtration of large macroamylase complexes.

In some cases, if a patient just has a high amylase level without macroamylasemia or belly pain, or doesn’t have any other signs or symptoms, no further tests might be needed. Additionally, the ratio of lipase to amylase is not a reliable test for alcoholic pancreatitis. However, if this ratio is more than 2, it could suggest alcoholic pancreatitis.

After pancreatic surgery, a low amylase level on the day of the operation can also indicate the patient is at low risk for postoperative complications, such as pancreatic fistula (an abnormal duct or passageway that allows fluid to drain from the pancreas). This could potentially guide doctors in deciding to remove surgical drains earlier.

Treatment Options for Hyperamylasemia

When your body generates excess amounts of the enzyme amylase – a condition known as hyperamylasemia – the recommended treatment typically involves addressing the underlying cause. An isolated increase in amylase levels, particularly in people without symptoms and no suspected cause, is generally harmless and doesn’t require any medical intervention.

In cases where hyperamylasemia is a result of acute pancreatitis (an inflammation of the pancreas), the treatment might include replenishing body fluids, managing pain and ensuring adequate nutritional intake. For hydration, a saltwater solution is given intravenously; the same applies to pain medication if needed. If the pancreatitis is relatively mild, the patient can usually return to eating a low-fat diet within 24 hours, provided their pain and vomiting symptoms are improving.

Hyperamylasemia is also a common complication following an ERCP (Endoscopic Retrograde Cholangiopancreatography), a procedure used to diagnose and treat conditions affecting the bile and pancreatic ducts. A recent study suggested that using a guidewire during this procedure significantly decreases the risk of elevated amylase levels post-ERCP. However, this adaptation has not been found to affect the development of pancreatitis.

If parotid disease – a disorder affecting the salivary glands, located in front of the ears – is the cause of hyperamylasemia, the best course of action is to begin appropriate treatment for the parotid condition. Once this condition is treated and inflammation in the salivary glands has subsided, the levels of amylase in the body will typically return to normal.

What else can Hyperamylasemia be?

When trying to figure out the reason for high levels of amylase in the blood, doctors consider various origins: it could be due to problems in the pancreas, in the salivary glands, or other miscellaneous causes. Here are the possible causes of hyperamylasemia (high blood amylase):

• Pancreatic causes:
  • Acute or chronic pancreatitis (inflammation of the pancreas)
  • Complications following acute pancreatitis, such as an abscess, pseudocyst, or ascites
  • Physical trauma (for example, from endoscopic retrograde cholangiopancreatography -ERCP-, blunt trauma, or recent surgery)
  • Pancreatic cancer
• Salivary gland issues:
  • Blocked salivary gland or salivary gland stones
  • Chronic alcohol abuse
  • Physical trauma (for example, blunt trauma or recent surgery)
  • Mumps
  • Sjogren syndrome, an immune disorder that primarily causes dry eyes and mouth
  • Eating disorders like anorexia or bulimia
• Miscellaneous causes:
  • Macroamylasemia, a condition in which a form of amylase circulates in the blood leading to high levels
  • Various types of cancer (ovarian, kidney, breast, thymoma, multiple myeloma, pheochromocytoma, colon cancer)
  • Inflammatory bowel disease
  • Renal failure
  • Liver diseases such as hepatitis, cirrhosis, or liver cancer
  • Ketotic and non-ketotic acidosis, metabolic conditions that result in too many ketones or acids in the body

What to expect with Hyperamylasemia

If the amount of an enzyme called amylase is high in your body for over a week after experiencing a bout of acute pancreatitis (a sudden inflammation of the pancreas), this could be a sign that the pancreatitis may occur again. However, it’s important to note that the level of amylase in your body doesn’t have a role in figuring out how serious the pancreatitis is or what caused it.

After doctors have diagnosed acute pancreatitis, it doesn’t help to continuously monitor the level of amylase in the patient’s body. Patients who have high levels of amylase for a long period of time are at a higher risk of developing complications linked to the pancreas. These complications could include death of tissues (necrosis), formation of fluid-filled sacs in the pancreas (pseudocysts), or a collection of pus due to infection (abscess).

Possible Complications When Diagnosed with Hyperamylasemia

Long-term high levels of amylase in the blood are often linked to complications of acute pancreatitis. These include conditions like the development of pseudocysts (false cysts filled with fluid), necrosis (death of body tissue), or abscess (collection of pus) in the pancreas. High amylase levels have also been independently associated with alcohol consumption.

Sometimes, doctors can use the ratio of lipase (another enzyme) to amylase in blood tests to determine the cause of acute pancreatitis. A higher ratio could suggest that alcohol is the main cause. However, a follow-up study was unable to confirm this finding.

Key Points:

• High amylase level over a long period can lead to pancreas complications such as pseudocysts, necrosis, or abscess.
• Alcohol use can independently raise amylase levels.
• A higher ratio of lipase to amylase might indicate alcohol as the main cause of acute pancreatitis, but this is still under investigation.

Preventing Hyperamylasemia

It’s important for patients to understand why certain tests, like a serum amylase test, are done. This test is often used by doctors to help diagnose acute pancreatitis, which is a sudden inflammation of the pancreas. However, it’s important to note that tracking changes in amylase levels over time isn’t helpful for determining how severe the pancreatitis is.

Doctors may also use imaging studies, such as ultrasounds or scans, along with blood tests, when they strongly suspect that a patient has acute pancreatitis. If a patient has high amylase levels (a condition known as hyperamylasemia) but there’s no other reason to suspect an underlying disease, no further tests or treatments are usually necessary.