Laboratory Tests for Diagnosing Pancreatitis and Monitoring the Condition

Pancreatitis involves the inflammation of the pancreas. Chronic pancreatitis is a long-term condition, while acute pancreatitis occurs for a short duration.

The pancreas is located below the liver and behind the stomach. It has a narrow, flat shape, and is around 6 inches long. The gland is split into three sections: the head, the tail, and the middle. The head section is connected to the start of the duodenum (small intestine).

The pancreas produces bicarbonate and digestive enzymes that are transported into the large pancreatic duct by small tubes. The large duct moves the bicarbonate and digestive enzymes from the tail section of the pancreas to the head section and subsequently into the small intestine.

Another duct running through the pancreas’s head section is the bile duct, which carries bile from the gallbladder and liver into the duodenum. The pancreatic duct and the bile duct converge before entering the small intestine through the same duodenum opening.

The pancreas is comprised of two distinct types of tissues that each perform special functions:

Exocrine Tissues

The exocrine pancreas manufactures, stores, and outputs strong digestive enzymes that break down carbohydrates, proteins, and fats in the duodenum. The enzymes are transported to the small intestine in an inactive state, ready to be activated as required. In addition to potent digestive enzymes, exocrine tissues also produce bicarbonate. Bicarbonate is used to neutralize stomach acid to allows for digestive enzyme activation.

Endocrine Tissues

The endocrine pancreas makes and releases hormones, including glucagon and insulin. Glucagon and insulin are used to regulate glucose levels in the blood and maintain efficient transportation of sugar into the cells that require it for energy.

Pancreatitis occurs when digestive enzymes become activated inside the pancreas. The activation of such enzymes causes irritation and damage to pancreatic tissues, leading to swelling and inflammation.

In the case of acute pancreatitis, the onset of inflammation is rapid but only lasts a couple to days.

The causes of pancreatitis are long-term alcohol abuse and gallstones that clog the pancreatic duct. Severe attacks can necessitate a lengthy stay in a hospital so that serious complications can be treated, and the condition can be monitored. With modern treatment methods, mild cases can often be cured in a few days. Furthermore, during mild attacks, the pancreas is likely to return to normal functioning after healing.

Recurrent acute pancreatitis attacks can lead to chronic pancreatitis, which is long-lasting pancreas inflammation and swelling. The leading cause of chronic pancreatitis is long-term alcohol abuse. Those who smoke cigarettes are also at an increased risk of developing the condition.

Chronic pancreatitis can result in the development of scar tissue inside the pancreas, which can impair its functionality. A malfunctioning pancreas can cause diabetes and digestive problems.

Pancreatitis is more common in males than in females. Cases of the condition are also becoming more numerous in the USA, however, the reasons for the increasing number of cases are unclear. Around 2750,000 individuals are hospitalized for acute pancreatitis every year. Cases of chronic pancreatitis are less common, with hospitalization numbers of around 86,000 individuals each year.

Causes of Pancreatitis

As previously mentioned, the main causes of the condition are long-term alcohol abuse and gallstones. Additional causes can include:

  • Viral infections, including Epstein-Barr virus and mumps
  • Pancreatic cancer
  • Injury to the gland organ
  • Use of pharmaceutical medications like estrogen pills and valproic acid
  • High blood calcium levels or triglyceride levels
  • Cystic fibrosis
  • Carrier of the gene responsible for cystic fibrosis
  • Certain autoimmune conditions
  • Inherited pancreas defects

In some cases, the exact cause of acute or chronic pancreatitis remains unclear.

Pancreatitis can be prevalent in families, and several genes have been identified as being associated with an increased risk of developing the condition.

Signs & Symptoms

1. Acute 

Here are some of the most common acute pancreatitis signs and symptoms:

  • Fever
  • Nausea
  • Vomiting
  • Severe upper abdominal pain. The pain often worsens when lying flat or after eating and can radiate to the spine.
  • Racing pulse
  • Abdominal tenderness and swelling

An attack of acute pancreatitis causes local inflammation, hemorrhage, and swelling of the pancreas, which typically disappears after treatment, leaving no permanent damage. However, sometimes such an attack can be very severe and lead to complications, such as:

  • Kidney failure
  • Infection
  • Necrosis (tissue death)
  • Trouble breathing
  • Pancreatic pseudocysts (sacs full of dead tissue and fluid, which often become infected)
  • Low blood pressure

If you notice any of the signs and symptoms of acute pancreatitis, it’s vital that you contact a healthcare professional as the severity of symptoms does not always correspond to the amount of damage occurring. Some of the signs and symptoms of the condition can also be signs of a different medical condition that requires different treatment methods.

Swift diagnosis and treatment of acute pancreatitis are essential for preventing complications, limiting infection, and reducing inflammation. Repeated attacks of acute pancreatitis can result in chronic pancreatitis.

2. Chronic 

Individuals suffering from chronic pancreatitis might experience recurring attacks that have symptoms similar to a bout of acute pancreatitis. As the condition progresses, the frequency of the attacks often increases. Pain resulting from chronic pancreatitis can be very severe and intermittent or continuous. The pain often worsens after consuming food or drinking, in particular alcoholic beverages.

Over time, chronic pancreatitis can lead to the gland organ becoming scarred and unable to manufacture digestive enzymes properly. This can result in:

  • Malnutrition
  • Weight loss
  • Pancreatic insufficiency
  • Pancreatic pseudocysts (sacs full of dead tissue and fluid, which often become infected)
  • Ascites (fluid buildup in the abdomen)
  • Fatty, foul-smelling stools
  • Once the cells in the pancreas that make insulin are severely damaged, diabetes can develop

Diagnosis

The diagnosis of pancreatitis requires a physical exam, medical history check, imaging tests, and blood tests. Two out of the following three criteria must be met for an acute pancreatitis diagnosis:

1. “Characteristic” imaging results

2. Pain in the abdominal area that is characteristic of the condition

3. Lipase levels or amylase levels three times greater than the normal upper limit

Lab Tests

Blood tests are carried out to measure amylase and lipase levels in the blood. Amylase and lipase are digestive enzymes produced by the pancreas.

1. Lipase level test (preferred choice)

Lipase is an enzyme that digests fats. The test of lipase levels is more accurate than the test for amylase levels for diagnosing diseases of the pancreas, especially acute pancreatitis and acute alcoholic pancreatitis. Levels of the enzyme begin to rise between 4 and 8 hours following the onset of various pancreatitis symptoms. They will typically fall back to normal levels within seven days. If the lipase level is three times higher than the normal upper limit, acute pancreatitis is diagnosed. As chronic pancreatitis worsens, levels of lipase can be normal or below normal.

2. Amylase level test

Amylase is an enzyme that digests carbohydrates. Although the amylase test can signal pancreatic diseases, it is not as specific as the lipase test. This means elevated amylase levels can indicate an issue, but the cause might not be linked to the pancreas. Amylase levels begin to increase between 2 and 12 hours following the onset of various acute pancreatitis symptoms and generally return to normal levels within seven days. If levels are three times higher than the normal upper limit, acute pancreatitis is probable. Amylase levels can also be monitored in individuals with chronic pancreatitis. The levels will typically be somewhat elevated until cell damage to cells that manufacture the enzyme becomes extensive, at which stage amylase levels in the blood are likely to be decreased.

There are further blood tests than can be used to aid in the diagnosis of acute pancreatitis or help to detect complications. Such tests can include:

Triglycerides

Complete blood count

Comprehensive metabolic panel

Calcium

Glucose

Magnesium

C-reactive protein

In addition to blood tests, other lab tests can be used to help diagnose and monitor chronic pancreatitis, including:

  • Fecal fat test to detect an excess of fat in a stool sample, which is often one of the first signs of pancreatic insufficiency. The stool elastase test (see below) is easier to carry out, so the fecal fat test is less commonly done.
  • Stool elastase test to measure the levels of elastase (a pancreatic enzyme) in a stool sample. Pancreatic insufficiency results in reduced levels of the enzyme in stools. Chronic pancreatitis can cause pancreatic insufficiency.
  • Immunoreactive trypsinogen (IRT) blood test to measure trypsinogen levels. Trypsinogen, made by the pancreas, is the inactive precursor of trypsin, an enzyme that digests protein. Elevated IRT levels can be a sign.
  • Chymotrypsin test to measure chymotrypsin in stools. Chymotrypsin is a pancreatic enzyme that digests proteins, and an absence of it in stools signifies pancreatic insufficiency.
  • Genetic mutation tests, such as cystic fibrosis gene mutation testing and test for other genes known to cause hereditary pancreatitis.
  • Chloride test (aka sweat test) to diagnose cystic fibrosis.