What are pancreatic pseudocysts?

Pancreatic pseudocysts are collections of leaked pancreatic fluids. They may form next to the pancreas during pancreatitis.

The pancreas is an organ that sits behind your stomach. It makes fluids that flow through a duct into the small intestine. These fluids help you digest food. The pancreas also releases hormones to help control blood sugar. This includes insulin.

Pancreatitis is inflammation of the pancreas. When the pancreas gets inflamed, it may leak digestive enzymes. This damages the pancreas. It causes collections of fluid to form. These are called pancreatic pseudocysts.

Pancreatic pseudocysts are different from true pancreatic cysts. Both cysts and pseudocysts are collections of fluid. A true cyst is a closed structure. It has a lining of cells that separates it from the nearby tissue. A pseudocyst isn’t closed. It doesn’t have a lining of cells separating it from the nearby tissue. This difference is important. The cause of these conditions and treatments may vary. Also, some true cysts are cancer. But pancreatic pseudocysts rarely are.

Pancreatic pseudocysts are not the same thing as pancreatic abscesses. These abscesses are also known as walled-off pancreatic necrosis. Abscesses that form during pancreatitis contain fluid and semisolid parts. These usually don't go away on their own and need treatment to be removed. Pseudocysts contain only fluid.

Pancreatic pseudocysts happen in around 1 in 10 people with chronic pancreatitis. It’s more common in people assigned male at birth than in others. It can affect people of all ages.

What causes pancreatic pseudocysts?

Pseudocysts form when the cells of the pancreas become inflamed or are injured. Pancreatic enzymes start to leak. Leaking of the enzymes harms the tissue of the pancreas.

Pancreatic pseudocysts are more common after an episode of sudden (acute) pancreatitis. People with chronic pancreatitis more often get pseudocysts. They may also form if you have long-term pancreas inflammation (chronic pancreatitis).

Having gallstones and drinking a lot of alcohol are the 2 most common causes of pancreatitis. Some other causes of it include:

• Pancreas injury

• Pancreas infection

• Pancreatic tumor

• High calcium levels in your blood

• Very high levels of blood fats (cholesterol)

• Pancreatic damage from medicines

• Autoimmune diseases

• Conditions that run in your family that harm the pancreas, such as cystic fibrosis

Who is at risk for pancreatic pseudocysts?

You may have a higher risk for pseudocysts if you have a health issue that can cause pancreatitis. These include gallstones. You may be able to reduce your risk by treating your health condition. Drinking less alcohol may also lower your risk.

What are the symptoms of pancreatic pseudocysts?

Symptoms of pancreatitis and pseudocysts may include:

• Stomach pain. This may go around to your back.

• Fever

• Swollen belly (abdomen)

• Nausea and vomiting

• An abdominal mass found on physical exam

• Yellowing of the skin or eyes (jaundice)

Severe pancreatitis may also cause fluid loss (dehydration) and low blood pressure. Complications from pseudocysts may cause other symptoms.

Sometimes you may not have any symptoms. The pseudocyst might show up on an imaging test done for another reason.

How are pancreatic pseudocysts diagnosed?

Your healthcare provider will ask about your health history, symptoms, and other health conditions. They will also give you an exam, focusing on your belly.  

You may have tests. These may include:

• Tests that look for high levels of pancreatic enzymes in your blood

• Tests for other substances. These include sodium, potassium, and glucose.

• Tests to find the cause of the pancreatitis. These include tests for blood fats.

• Imaging tests. These may include an abdominal ultrasound, CT scan or MRI.

Your healthcare provider will rule out other causes of your symptoms. They will check you for an ulcer, gallbladder inflammation, and pancreatic cancer.

Your healthcare provider can often confirm a pseudocyst with CT or with another imaging test, such as MRI. If the diagnosis is still unclear, your healthcare team may take a sample of the fluid in your cyst. This test is done with a long, thin needle and imaging guidance. Your healthcare team will need to see if you have a pseudocyst instead of a true pancreatic cyst (which might be cancer) or a pus-filled infection (abscess).

How are pancreatic pseudocysts treated?

Treatment often happens in 2 parts. You will have treatment for pancreatitis and treatment for the pseudocyst. To treat the pancreatitis, you may need:

• Rest

• IV (intravenous) fluids

• Pain medicines

• Medicines to prevent vomiting

You may also need nasogastric feedings. In nasogastric feeding, you get nutrition in liquid form. You will get it through a long, thin tube. This tube is put through your nose and into your stomach. Sometimes the tube is placed into a part of the small intestine. This is called nasojejunal feeding. You may also not be able to eat or drink anything for a while so that your pancreas can rest.

Treatment for the pseudocyst may vary. Many pseudocysts will go away on their own with supportive care. Your healthcare provider may just watch your pseudocyst. Your healthcare provider will carefully monitor you for symptoms of complications. You may also need another imaging test to check if your pseudocyst goes away.

If your pseudocyst is large, causes symptoms, or hasn’t gone away over time, your healthcare provider may treat it. They may put a thin tube (catheter) through your belly to drain the pseudocyst. This is done with the help of medical imaging. Or the cyst may be drained endoscopically. This means it may be done by entering the pancreatic pseudocyst through your stomach, or the first part of the small intestine (duodenum). In other cases, you may need surgery to drain your pseudocyst.

What are possible complications of pancreatic pseudocysts?

Pseudocysts can cause severe issues. They can even cause death if they are not treated right away. Most problems are fairly uncommon. Possible complications include:

• Cyst infection. This may lead to sepsis and shock.

• Cyst hemorrhage

• Bleeding into your spleen or a blood clot in a spleen vein

• Blockage of the bile duct. This may cause yellowing of your skin and eyes (jaundice).

• Portal hypertension

• Gastric outlet obstruction

• Cyst rupture

If you have these problems, you will likely have surgery or another treatment to drain the cyst.

When should I call my healthcare provider?

If you have a pancreatic pseudocyst, know that it may cause complications. Many of these need medical care right away. See your healthcare provider right away for any severe or sudden symptoms. These include:

• Throwing up blood

• Fever

• Dizziness

• Yellowing of your skin (jaundice)

• Severe stomach pain

Key points about pancreatic pseudocysts

• Pancreatic pseudocysts are collections of leaked pancreatic fluids. They may form next to the pancreas during pancreatitis.

• Having gallstones and drinking a lot of alcohol are the 2 most common causes of pancreatitis.

• Most people with pseudocysts will have stomach pain, vomiting, and other symptoms of pancreatitis.

• Your healthcare provider can likely diagnose a pseudocyst with a CT or another imaging test.

• Many pseudocysts get better without treatment. If your pseudocyst is large, causes symptoms, or hasn’t gone away over time, your healthcare provider may drain it.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

• Know the reason for your visit and what you want to happen.

• Before your visit, write down questions you want answered.

• Bring someone with you to help you ask questions and remember what your provider tells you.

• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.

• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are and when they should be reported.

• Ask if your condition can be treated in other ways.

• Know why a test or procedure is recommended and what the results could mean.

• Know what to expect if you do not take the medicine or have the test or procedure.

• If you have a follow-up appointment, write down the date, time, and purpose for that visit.

• Know how you can contact your provider if you have questions, especially after office hours and on weekends and holidays.