Acute Pancreatitis

What is acute pancreatitis?

Acute pancreatitis is a sudden inflammatory disease of the pancreas. It can run at different degrees of severity, from a mild illness that settles within a few days to a serious one that may need intensive care.

The pancreas is an important organ lying behind the stomach, producing the enzymes needed for digestion as well as the hormones that regulate the blood sugar.

Normally the digestive enzymes the pancreas produces become active in the bowel. In acute pancreatitis, the damage and the inflammatory response that develop in the pancreatic tissue can affect the pancreas itself and sometimes other organs.

What are the commonest causes of acute pancreatitis?

Gallstones

Gallstones are one of the most important causes of acute pancreatitis.

A small stone or biliary sludge leaving the gallbladder can cause temporary or permanent obstruction at the point where the bile and pancreatic ducts open into the bowel. Acute pancreatitis may follow.

In suitable patients who have had pancreatitis due to a gallstone, removal of the gallbladder may come into consideration to prevent another attack.

Alcohol

Drinking alcohol in large amounts is another important cause of acute pancreatitis.

The effect of alcohol on the pancreas varies from person to person. Not everyone who drinks alcohol has pancreatitis; but in patients who do develop pancreatitis, stopping alcohol matters for preventing further attacks.

A raised triglyceride level

A very high level of triglycerides in the blood can cause acute pancreatitis.

At very high triglyceride values in particular, the risk of pancreatitis rises markedly.

Medicines

Some medicines can uncommonly cause acute pancreatitis. But before deciding that a medicine a patient is taking has caused their pancreatitis, the commoner causes must be investigated.

Medicines should not be stopped without consulting a doctor.

Other causes

Acute pancreatitis can also develop:

• After ERCP,
• With an excessive rise in the calcium in the blood,
• With certain infections,
• With structural problems in the pancreas or the bile ducts,
• In certain genetic conditions,
• After injury.

Sometimes no definite cause is found despite the investigations carried out. This is called idiopathic acute pancreatitis.

What are the symptoms of acute pancreatitis?

The most typical symptom is upper abdominal pain of sudden onset, generally severe.

The pain:

• May be felt in the upper middle part of the abdomen,
• May spread through to the back,
• May continue for hours or days,
• May be accompanied by nausea and vomiting.

In some patients there may be bloating of the abdomen, fever, a rapid pulse and a deterioration in general condition.

In severe disease, more serious problems such as low blood pressure, shortness of breath or a disturbance of kidney function may develop.

How is acute pancreatitis diagnosed?

Three main features are generally assessed in making the diagnosis:

1. Typical abdominal pain consistent with acute pancreatitis,
2. A rise in the blood lipase or amylase to more than three times the upper limit of normal,
3. Findings on imaging consistent with acute pancreatitis.

Generally at least two of these three criteria are enough for the diagnosis.

Which matters more, lipase or amylase?

Today lipase is generally the blood test of choice in diagnosing acute pancreatitis.

Lipase is more specific than amylase for diseases of the pancreas, and it can stay raised for longer.

But how high the blood tests are does not on its own show how severe the illness will be.

A very high lipase, for instance, does not necessarily mean very severe pancreatitis.

Does every patient need a CT scan?

No.

In a patient with typical abdominal pain and a markedly raised lipase or amylase, an immediate CT scan to confirm the diagnosis is not always necessary.

CT may be used particularly where:

• The diagnosis is uncertain,
• The patient is not improving as expected,
• A complication is suspected,
• The course of the illness needs to be assessed.

For looking for gallstones, ultrasound of the abdomen is an important first investigation.

Where needed, methods such as MRCP or endoscopic ultrasound (EUS) may be used.

How serious a disease is acute pancreatitis?

In a substantial proportion of patients with acute pancreatitis the illness runs a mild course and settles with supportive treatment.

But in some patients complications around the pancreas, or disturbance of other organs, may develop.

The course of the illness can broadly be assessed as:

mild → moderately severe → severe.

The development of persistent organ failure in particular is one of the important markers of severe disease.

For this reason, once acute pancreatitis is diagnosed, attention goes not only to the pancreatic enzymes but to many factors — the patient’s blood pressure, breathing, kidney function, fluid state and general clinical course.

How is acute pancreatitis treated?

Treatment of acute pancreatitis is planned according to the cause and the severity of the illness.

The main elements of treatment are:

• Appropriate fluid treatment,
• Control of pain,
• Treatment of nausea and vomiting,
• Arrangement of nutrition,
• Correction of electrolyte and metabolic problems,
• Close observation of the patient,
• Treatment of the condition that caused the pancreatitis.

Severely ill patients may be looked after in intensive care.

Does the patient have to go without food?

In the past it was common practice to keep patients with acute pancreatitis without food for a long period, to “rest” the pancreas.

This approach has changed.

In mild acute pancreatitis, starting to eat by mouth early is preferred as soon as nausea, vomiting and pain allow.

If the patient cannot take enough by mouth but their bowel can be used, enteral feeding through a tube may be preferred where necessary.

Unnecessary fasting for long periods is not recommended.

Are antibiotics used in acute pancreatitis?

Not every patient with acute pancreatitis is given an antibiotic.

Acute pancreatitis itself is mostly not a bacterial infection. For this reason the routine use of antibiotics as a preventive measure is not recommended, particularly in sterile pancreatic necrosis.

An antibiotic may properly be used:

• Where infected pancreatic necrosis is suspected,
• Where there is infection of the bile duct (cholangitis),
• Where a chest, urinary or other bacterial infection has developed.

Is ERCP done in every gallstone pancreatitis?

No.

The development of acute pancreatitis due to a gallstone does not on its own mean that an urgent ERCP is needed.

Early ERCP may be needed particularly in patients in whom cholangitis or continuing obstruction of the bile duct is suspected.

In other patients, whether an ERCP is needed is decided according to the clinical findings and the results of imaging.

When is the gallbladder removed?

In mild acute pancreatitis due to a gallstone, removing the gallbladder during the same hospital admission may be preferred in suitable patients, to prevent a further attack of pancreatitis.

But in patients with severe pancreatitis, fluid collections around the pancreas or other complications, the timing of the operation may be planned differently.

What is pancreatic necrosis?

In severe acute pancreatitis, a disturbance of the circulation and death of tissue may develop in part of the pancreas or of the fatty tissue around it. This is called necrosis.

Necrosis is not always infected.

Sterile necrosis and infected necrosis are different from one another, and their treatments may differ too.

Infected necrosis is a serious complication. Where necessary, antibiotics, endoscopic or radiological drainage, or surgical intervention may be used.

Today, in suitable patients, less invasive and stepwise treatment methods are preferred as far as possible.

What is a pseudocyst?

After acute pancreatitis, collections of fluid may develop around the pancreas in some patients.

Some of these disappear on their own over time. Others develop a clear wall around them and become a pancreatic pseudocyst.

Not every pseudocyst has to be drained.

Interventional treatment may be needed for collections that cause problems such as pain, infection, enlargement, bleeding, or pressure on the stomach, the bowel or the bile ducts.

Does acute pancreatitis recur?

Yes.

If the factor that caused the pancreatitis is not removed, further attacks may develop.

For instance:

• Gallstones not being treated,
• Alcohol being continued,
• Very high triglyceride levels not being controlled,
• Certain anatomical or genetic problems being present

can all increase the risk of recurrent pancreatitis.

Repeated attacks of acute pancreatitis can, in some patients, progress over time to chronic pancreatitis.

What should be attended to after acute pancreatitis?

After leaving hospital, what matters is not only that the pancreatitis has settled but that the reason it developed has been established.

According to the cause, what may be planned includes:

• An operation on the gallbladder,
• Stopping alcohol,
• Stopping smoking,
• Treatment of a raised triglyceride level,
• A review of the medicines being taken,
• Further investigation of the pancreas and bile ducts where needed.

In pancreatitis of unexplained cause or recurrent pancreatitis in particular, EUS, MRCP or, in selected patients, other investigations may be needed.

When is emergency assessment needed?

Where there is newly begun, severe upper abdominal pain that does not pass, particularly if it spreads through to the back and is accompanied by nausea and vomiting, medical assessment should not be delayed.

Emergency assessment is needed if this is accompanied by:

• Fever,
• Jaundice,
• Persistent vomiting,
• Shortness of breath,
• Fainting or marked weakness,
• Low blood pressure.

Remember

Acute pancreatitis can run a variable course, from a mild illness to a picture that can threaten life.

Gallstones and alcohol are important causes; but a raised triglyceride level, medicines and other causes should also be investigated.

Not every patient needs an urgent CT scan, antibiotics or an ERCP. In current treatment the main approach is appropriate fluid and pain treatment, early feeding where possible, close monitoring of the severity of the illness, and removal of the cause that led to the pancreatitis.