Pancreatitis is an inflammation of the pancreas, an important organ that produces enzymes to help digest food as well as hormones like insulin to regulate blood sugar. There are two main types of pancreatitis: acute and chronic. Acute pancreatitis involves sudden inflammation that develops over a few days and may resolve in a few weeks. Chronic pancreatitis involves persistent inflammation that causes permanent damage to the pancreas over many years.
Both types of pancreatitis have similar causes, symptoms, and treatments. The main difference is the duration and reversibility of the inflammation and damage. Acute cases may resolve completely and not return while chronic pancreatitis is an ongoing inflammatory condition.
There are three key criteria that must be met for a diagnosis of pancreatitis:
Abdominal Pain
The hallmark symptom of pancreatitis is abdominal pain that classically occurs in the upper abdomen and often radiates to the back. It is usually a sudden and severe pain described as boring, sharp, or stabbing.
The abdominal pain is due to inflammation of the pancreas itself as well as inflammation of surrounding tissues and organs that are irritated by pancreatic enzymes leaking out of damaged cells. This pain tends to be made worse after eating, especially fatty foods.
Abdominal pain from pancreatitis usually lasts for several days but may persist for a week or more in severe cases. The pain may be constant or fluctuate in intensity. It typically reaches peak intensity over the first 12-24 hours.
While abdominal pain is also seen with many other abdominal conditions, the characteristics and location of the pain can help distinguish pancreatitis when considered together with other criteria. Mild cases of acute pancreatitis may have minimal abdominal pain.
Elevated Pancreatic Enzymes
The pancreas produces and secretes many digestive enzymes that help breakdown fats, proteins and carbohydrates. Normally these enzymes do not become activated to digest food until they reach the small intestine.
In pancreatitis, these enzymes become prematurely activated inside the pancreas, starting to digest the pancreatic cells themselves. This causes damage and inflammation.
The most important enzymes are amylase and lipase. Blood tests nearly always show elevated levels of these enzymes during an episode of acute pancreatitis. The levels may be elevated 3-5 times higher than the normal range or even more in severe cases.
The enzyme levels begin to rise within 12-24 hours of the start of symptoms and may remain elevated for 1-2 weeks as the pancreas recovers. In chronic pancreatitis, the enzyme levels may be normal or only mildly elevated since there is already permanent damage.
Checking serum amylase and lipase is important to confirm a diagnosis. The degree of elevation can also indicate the severity of an attack. However, some other conditions can also cause mild elevations in these enzymes.
Radiologic Findings
Various imaging tests can confirm the diagnosis by revealing characteristic findings associated with inflammation and injury of the pancreas. These include:
– Ultrasound: Can show an enlarged pancreas as well as inflammation of surrounding fatty tissues. It cannot reliably detect mild cases.
– CT scan: Often the preferred test. Can show inflammation of the pancreas and peri-pancreatic fluid collections. It can also detect gallstones if present.
– MRI: Similar to CT in detecting pancreatic inflammation, fluid collections, and stones. May give clearer images than CT.
– ERCP: Uses endoscopy to inject dye into the pancreatic ducts and take x-rays. Can detect narrowing, blockage, or leakage of ducts.
– MRCP: Non-invasive MRI to visualize pancreatic ducts similar to ERCP.
The characteristic radiological findings for acute pancreatitis may include:
– Pancreatic enlargement
– Blurring of pancreatic margins and contours
– Areas of reduced contrast enhancement
– Inflammatory changes spreading into peri-pancreatic fat
– Fluid collections around the pancreas
Pancreatitis often resolves without complications seen on imaging. In more severe or prolonged cases, pancreatic necrosis, abscesses, pseudocysts, or benign strictures may be seen. Chronic pancreatitis causes irreversible scarring and calcification of the pancreas detectable on CT scan.
Mild, Moderate, and Severe Pancreatitis
Pancreatitis occurs across a spectrum of severity. There are some general guidelines to categorize cases as mild, moderately severe, or severe based on clinical and lab criteria:
Mild Acute Pancreatitis
– Minimal organ dysfunction
– Unremarkable morphology on imaging
– Usually resolves in the first week
– Typically not life-threatening
– Minimal fluid loss or metabolic disturbance
Moderately Severe Acute Pancreatitis
– Organ failure lasting less than 48 hours
– Local complications seen on imaging (necrosis, abscess, pseudocyst)
– Requires prolonged hospitalization
Severe Acute Pancreatitis
– Persistent organ failure (>48 hours)
– Often requires ICU admission
– Associated with a high mortality rate
– Diffuse or necrotizing pancreatitis on imaging
Distinguishing mild cases from more severe ones guides treatment and determines prognosis. Around 80% of acute pancreatitis cases are mild and usually resolve with conservative treatment. The remaining 20% that are moderately severe or severe require more intensive care.
Causes
There are numerous causes that can trigger pancreatitis by promoting premature activation of pancreatic enzymes inside the pancreas rather than in the small intestine. Common causes include:
– Gallstones – The most common cause, seen in 35-40% of cases
– Alcoholism – The second most common cause overall; the most common in adults
– Hypertriglyceridemia – Caused by high blood fats
– Medications – Such as steroids, diuretics, anti-HIV drugs, azathioprine
– ERCP procedure – May damage the pancreas ducts
– Trauma/injury – Blunt injury to the upper abdomen
– Infections – Mumps, Coxsackie B virus
– Autoimmune disorders
– Tumors – Pancreatic or ampullary cancers
– Pancreas divisum – A congenital condition with two drainage ducts
– Idiopathic – No cause found in ~25% of cases
Identifying and addressing the underlying cause is an important part of treatment. For example, stopping a medication that triggered pancreatitis or treating gallstones to prevent recurrence. When no cause is found, it is considered idiopathic.
Risk Factors
Factors that increase the risk of developing pancreatitis include:
– Gallstones
– Alcoholism
– Smoking
– Obesity
– Hypertriglyceridemia
– Diabetes
– Chronic kidney disease
– HIV infection
– Family history of pancreatitis
– Certain medications (see causes above)
– Age older than 60
– Male gender
Avoiding modifiable risk factors can help prevent episodes of pancreatitis, especially in patients who have already had an attack or have an underlying condition that predisposes them to it.
Symptoms
The symptoms of acute and chronic pancreatitis are similar and may include:
– Upper abdominal pain that can radiate to the back
– Nausea and vomiting
– Fever
– Rapid heartbeat
– Diarrhea
– Bloating and gas
– Loss of appetite and weight loss
– Jaundice – yellowing skin and eyes
– Generalized body weakness
More severe cases can lead to:
– Dehydration
– Breathing difficulty
– Confusion
– Shock
Chronic pancreatitis causes persistent digestive problems and diabetes due to the gradual destruction of the pancreas over years. There may also be oily stools from the inability to properly digest fats.
Diagnosis
Diagnosing pancreatitis requires:
– Characteristic upper abdominal pain
– Elevated pancreatic enzymes in the blood
– Radiologic findings of pancreatic inflammation
Additional diagnostic tests may include:
– Blood tests – To assess dehydration and electrolyte abnormalities. May show high glucose and fatty acids.
– Liver tests – Bilirubin and AST/ALT may be elevated if bile duct obstructed.
– Lipase – More specific for pancreatitis than amylase.
– Serum calcium – Low calcium can occur due to saponification.
– Urinalysis – Tests for ketones caused by fat breakdown.
– Imaging – CT, MRI, ultrasound (described above)
– ERCP – Helps identify gallstones and duct abnormalities.
– EUS – Endoscopic ultrasound to examine the pancreas.
– Stool tests – To rule out infectious causes.
Treatment
The treatment of pancreatitis aims to:
1. Manage pain and nausea
2. Correct fluid and electrolyte losses
3. Give nutrition support
4. Prevent enzyme and calcium abnormalities
5. Treat any complications detected
The main principles for treating acute pancreatitis include:
– Withholding oral food and fluids temporarily
– Providing IV fluid rehydration
– Controlling pain with medications
– Preventing enzyme activation inside the pancreas
– Monitoring for signs of severity/complications
– Checking for improvement with repeat lipase tests
Mild cases may only require a few days of this conservative treatment before resuming an oral diet. Severe cases require ICU monitoring and urgent treatment of any necrosis, abscesses, or organ failure detected.
Treatment for chronic pancreatitis focuses on managing the ongoing symptoms of pancreatic insufficiency and diabetes. This may require long-term use of enzyme supplements and insulin. Surgery is sometimes needed to relieve pain or drain pseudocysts.
Complications
Potential complications of pancreatitis include:
– Shock – Due to fluid sequestration
– Pleural effusions
– Acute respiratory distress syndrome
– Pancreatic necrosis
– Cyst formation
– Abscess
– Pseudocyst
– Disseminated intravascular coagulation
– Acute kidney failure
– Pancreatic insufficiency
– Diabetes mellitus
– Malnutrition
Severe necrotizing pancreatitis has a high mortality rate. Even after recovery, recurrent acute attacks can lead to chronic pancreatitis. Prompt treatment of complications is crucial.
Prognosis
The prognosis for pancreatitis depends on the severity and cause. Overall:
– Mild acute pancreatitis has a mortality rate less than 1%
– Moderately severe has a mortality rate around 6%
– Severe cases have a mortality rate of 15-30%
With treatment, most mild cases resolve completely within days to weeks and do not cause permanent damage. More than 80% of patients have no recurrence.
However, severe acute pancreatitis can have serious complications with a prolonged recovery time. Recurrent bouts of acute pancreatitis often progress to chronic pancreatitis, especially if the cause it not addressed.
Chronic pancreatitis has an increased mortality risk due to the development of diabetes and malnutrition over time. Stopping alcohol use and smoking can slow the progression of chronic disease.
Prevention
Strategies to help prevent pancreatitis include:
– Avoiding heavy alcohol use
– Maintaining healthy weight
– Managing diabetes and high blood fats if present
– Taking steps to prevent gallstones
– Avoiding certain medications when possible
– Stopping cigarette smoking
– Not skipping meals or fasting for long periods
– Staying hydrated
For those with chronic or recurrent pancreatitis, these steps may also help prevent acute flares:
– Following a low-fat diet
– Taking pancreatic enzyme supplements
– Monitoring blood glucose closely
– Taking vitamins/minerals to prevent deficiencies
– Avoiding known triggers like alcohol
– Taking medication to prevent gallstone attacks
Conclusion
In summary, the three key criteria for diagnosing pancreatitis are:
1. Upper abdominal pain, usually severe and lasting over a week
2. Elevated blood levels of pancreatic enzymes like amylase and lipase
3. Radiologic findings on CT, MRI, or ultrasound confirming inflammation
Pancreatitis occurs in acute episodes lasting days to weeks or as a chronic condition. It has numerous causes, most commonly gallstones and alcoholism. Diagnosis is made by the classic symptoms and confirmed with lab tests and imaging.
Treatment involves fluid resuscitation, pain control, and prevention of complications. Mild cases usually resolve fully, while severe pancreatitis can lead to organ failure, pancreatic necrosis, and long-term damage. Preventing modifiable risk factors can reduce the risk of pancreatitis.