What Is Acute Pancreatitis? Symptoms, Causes, Diagnosis and Treatment

What Is the Pancreas and What Does It Do?

The pancreas is an organ located in the upper abdomen behind the stomach. It has important digestive and hormonal functions.

Its two main functions are:

• Digestion: It produces enzymes that help digest fats, proteins and carbohydrates and delivers them to the small intestine.
• Hormone production: It produces hormones including insulin and glucagon that contribute to regulation of blood glucose.

What Is Pancreatitis?

Pancreatitis is inflammation of the pancreas.

In acute pancreatitis, premature activation of pancreatic enzymes and the resulting inflammatory response can injure pancreatic and surrounding tissues.

The illness may resolve within a few days in some patients, while others can develop pancreatic necrosis, fluid collections or organ failure.

Acute vs Chronic Pancreatitis

Acute pancreatitis develops suddenly and often resolves with appropriate supportive treatment.

Chronic pancreatitis involves long-term inflammation and permanent structural damage to the pancreas and may eventually cause pancreatic enzyme insufficiency, weight loss or diabetes.

What Are the Symptoms of Acute Pancreatitis?

The most characteristic symptom is significant upper abdominal pain.

Symptoms can include:

• Severe or persistent upper abdominal pain
• Pain radiating to the back
• Nausea
• Vomiting
• Abdominal tenderness or distension
• Fever
• Increased heart rate

Patients with biliary obstruction may also develop jaundice or dark urine.

Which Symptoms Require Urgent Medical Assessment?

How Is Acute Pancreatitis Diagnosed?

Diagnosis generally relies on three criteria:

1. Typical abdominal pain consistent with acute pancreatitis
2. Serum lipase or amylase at least three times the upper limit of normal
3. Imaging findings consistent with acute pancreatitis

The presence of at least two of these three criteria supports the diagnosis.

When Are Ultrasound, CT or MRI Used?

Routine early CT is not required when acute pancreatitis is clearly established by typical symptoms and laboratory testing.

Abdominal ultrasound is particularly important when gallstones or a biliary cause are suspected.

Contrast-enhanced CT or MRI may be used when the diagnosis is uncertain, the patient fails to improve as expected, or complications such as pancreatic necrosis are suspected.

What Causes Acute Pancreatitis?

Gallstones and alcohol are among the most common causes.

Other causes include:

• Severe hypertriglyceridaemia
• Certain medicines
• Post-ERCP pancreatitis
• Hypercalcaemia
• Abdominal trauma
• Certain infections
• Autoimmune disease
• Genetic factors
• Pancreatic or biliary tumours

In some patients, no definite cause can be identified despite appropriate investigation. This is termed idiopathic acute pancreatitis.

Gallstone Pancreatitis

A small gallstone can transiently or persistently obstruct the region where the common bile duct and pancreatic duct drain, triggering pancreatic inflammation.

Ultrasound assessment for gallstones is therefore important in patients presenting with acute pancreatitis.

Once the acute episode has settled, prevention of another episode may require removal of the gallbladder in appropriate patients.

Can High Triglycerides Cause Pancreatitis?

Yes. Severe hypertriglyceridaemia can cause acute pancreatitis.

Triglyceride concentrations above approximately 1,000 mg/dL strongly support hypertriglyceridaemia as a possible cause, particularly when more common causes such as gallstones and alcohol have been excluded.

Long-term triglyceride control is important for reducing the risk of recurrence.

How Serious Is Acute Pancreatitis?

The clinical course varies considerably.

Many cases are mild, but severe disease can involve persistent organ failure, pancreatic necrosis and systemic complications requiring intensive monitoring.

Respiratory, cardiovascular and kidney function are particularly important when assessing severity.

How Is Acute Pancreatitis Treated?

Treatment depends on severity and cause.

Initial management can include:

• Appropriate intravenous fluid therapy
• Pain control
• Treatment of nausea and vomiting
• Monitoring oxygenation and vital signs
• Monitoring renal function and fluid balance
• Early oral nutrition when tolerated

Fluid therapy should be adjusted according to haemodynamic response, age and cardiac or renal function. Excessive fluid administration may itself cause complications.

Nutrition in Acute Pancreatitis

Patients with mild acute pancreatitis can generally start oral food early when tolerated.

It is not always necessary to begin with clear liquids only; an appropriate low-fat soft or solid diet may be used.

When oral intake is inadequate, enteral nutrition is generally preferred over total parenteral nutrition.

When Is ERCP Needed in Acute Pancreatitis?

ERCP is an endoscopic procedure used to diagnose and treat selected biliary and pancreatic duct problems.

Urgent ERCP is not routinely required for every patient with gallstone pancreatitis.

It is particularly considered when:

• Acute cholangitis is present
• Persistent common bile duct obstruction is strongly suspected

Are Antibiotics Routinely Used?

No.

Routine prophylactic antibiotics are not recommended for uncomplicated acute pancreatitis or sterile pancreatic necrosis.

Antibiotics may be appropriate when infected pancreatic necrosis, cholangitis or another bacterial infection is confirmed or strongly suspected.

What Is Necrotising Pancreatitis?

Necrotising pancreatitis occurs when parts of the pancreas or surrounding tissues lose viability during an episode of acute pancreatitis.

Necrosis does not automatically mean infection or immediate surgery.

Sterile necrosis can often be managed without intervention.

When infected or symptomatic necrosis requires intervention, endoscopic or percutaneous drainage and minimally invasive step-up approaches may be used.

In clinically stable patients, intervention is often delayed where possible to allow the necrotic collection to become organised.

When Is Gallbladder Surgery Needed?

When gallstones caused the episode, cholecystectomy may be recommended to reduce the risk of recurrence.

For mild acute biliary pancreatitis, gallbladder removal is generally preferred during the same hospital admission when clinically appropriate.

Timing may be different in severe necrotising pancreatitis or when substantial local complications are present.

How Long Does Acute Pancreatitis Last?

Symptoms of mild acute pancreatitis often begin to improve within several days.

Recovery from severe or necrotising pancreatitis can take weeks or, in some patients, months.

How Can Recurrent Acute Pancreatitis Be Prevented?

Prevention depends on identifying and treating the underlying cause.

• Gallstones: Cholecystectomy may be recommended.
• Alcohol: Abstinence is recommended when alcohol is contributing to pancreatitis.
• Smoking: Smoking cessation is important because smoking is associated with recurrent and chronic pancreatitis.
• Hypertriglyceridaemia: Triglycerides should be controlled with appropriate dietary, metabolic and pharmacological management.
• Medication-related pancreatitis: The suspected medicine should be reviewed by the treating physician.

Recurrent or unexplained pancreatitis may require additional investigation with MRCP, endoscopic ultrasound or genetic assessment in selected patients.

Frequently Asked Questions

References

1. Academic Hospital. Pancreas and Acute Pancreatitis
2. Tenner S, et al. American College of Gastroenterology Guidelines: Management of Acute Pancreatitis. Am J Gastroenterol. 2024.
3. American Gastroenterological Association. Initial Management of Acute Pancreatitis
4. Trikudanathan G, et al. Diagnosis and Management of Acute Pancreatitis. Gastroenterology. 2024.