Intra-Abdominal Abscess

What is an intra-abdominal abscess?

An intra-abdominal abscess is a collection of pus or infected fluid that is surrounded by inflamed tissue inside the belly. It can involve any abdominal organ, or it can settle in the folds of the bowel.

What causes an intra-abdominal abscess?

Intra-abdominal abscesses sometimes happen because of another condition. An example might be appendicitis or diverticulitis. Many cases, however, happen after surgery. 

Abdominal abscesses can be caused by a bacterial infection. The most common bacteria to cause them are found in the stomach and intestines. One of these is Escherichia coli or E. coli. If left untreated, the bacteria will multiply and cause inflammation and kill healthy tissue.

Who is at risk for an intra-abdominal abscess?

Abdominal surgery or trauma and conditions, such as diabetes or inflammatory bowel disease, can put you at risk for an intra-abdominal abscess.

What are the symptoms of an intra-abdominal abscess?

If you've recently had surgery or trauma to an abdominal organ and have other risk factors, such as diabetes or inflammatory bowel disease, be on the lookout for signs of an intra-abdominal abscess.

Common symptoms include:

• Fever
• Belly pain
• Chest pain or shoulder pain 
• Lack of appetite
• Nausea and vomiting
• Change in bowel movements
• Rectal tenderness or fullness
• Mass in the belly
• Malnourishment

How is an intra-abdominal abscess diagnosed?

If you have symptoms of an intra-abdominal abscess, your healthcare provider may order tests to look for the presence of infection:

• Blood tests. Blood may be drawn to look for signs of infection or an intra-abdominal abscess. Particularly useful are tests that look at the number of white blood cells and other indicators of inflammation.
• Imaging tests. The best imaging test to check for an abscess is typically a computerized tomography or CT scan to see inside the belly. Other techniques, such as ultrasound or magnetic resonance imaging or MRI, may be used as well.
• Physical exam. As part of your exam, your healthcare provider will take your temperature and check for tenderness in the belly. Sometimes, the abscess can be felt as a mass in the midsection.

How is an intra-abdominal abscess treated?

Antibiotics may help treat an infection that could lead to an intra-abdominal abscess. But once the abscess has developed, antibiotics don't work as well for treatment. An intra-abdominal abscess often will need to be drained of fluid in order to heal. Typically, however, antibiotics are given along with draining the abscess. The type of antibiotic will depend on how severe your abscess is, your age, and any other conditions you may have.

One way to remove fluid is through percutaneous drainage. This is a process in which your healthcare provider guides a needle through the skin to the place where the infection is. This is a short procedure. Your healthcare provider will give you a sedative and a local anesthetic to help you relax and eliminate any discomfort or pain while it is being done. 

Another way to drain the abscess is with surgery. Surgical procedures may also involve repairing the condition that caused the abscess in the first place, such as a bowel perforation. Sometimes, more than one operation is needed.

Many times, a drainage catheter is left in the abscess cavity after it is drained. This will be checked by the healthcare team and removed when appropriate.

Your outcome will depend on the cause of your infection and how quickly you sought treatment. The right early treatment can significantly improve the outcome for people who develop intra-abdominal abscesses.  

While you are being treated for an intra-abdominal abscess, you may need nutritional support. This can be done by placing a feeding tube.

When should I call my healthcare provider?

If you've recently had surgery or trauma to an abdominal organ and have other risk factors, such as diabetes or inflammatory bowel disease, and you develop a fever, belly pain, nausea or vomiting, or other symptoms, you should immediately call your healthcare provider.

Key points about an intra-abdominal abscess

• An intra-abdominal abscess is a collection of pus or infected fluid that is surrounded by inflamed tissue inside the belly.
• An intra-abdominal abscess may be caused by bacteria. If left untreated, the bacteria will multiply and cause inflammation and kill healthy tissue
• If you've recently had surgery or trauma to an abdominal organ and have other risk factors, such as diabetes or inflammatory bowel disease, be on the lookout for signs of an intra-abdominal abscess.
• Early treatment can significantly improve the outcome for people who develop intra-abdominal abscesses

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.
• 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.