An abscess is a pocket of inflamed tissue filled with pus. Abscesses can form anywhere on the body (inside and outside), but are most commonly found on the surface of the skin. An abdominal abscess is a pus pocket located in the abdominal region, which includes:
- behind the abdominal cavity
- below the diaphragm
- in the middle of the abdomen
They can also form inside, on the surface, or near organs in the abdomen such as your liver, pancreas, and kidneys. Abdominal abscesses may form for no apparent reason or in conjunction with an operation or infection.
Abdominal abscesses are normally the result of trauma or infection in the area of the abscess. Intra-abdominal abscesses (abscesses within the abdomen) can be caused by the rupturing of an organ or infection spread from an organ into the abdomen. Depending on where the abdominal abscess is located, additional causes may be to blame.
These abscesses are usually formed due to a ruptured organ in the mid-abdominal region such as the intestines or appendix. They can also stem from diseases that affect the abdominal organs, such as irritable bowel disease. An infected wound in the area may also cause an abscess to form.
Below the Diaphragm
Abdominal abscesses form below the diaphragm when infected fluid makes its way to the area. This is normally the result of an internal injury or ruptured organ.
Behind the Abdominal Cavity
Abscesses behind the abdominal cavity (retroperitoneal cavity) form on or behind the membrane that lines the abdominal organs and cavity called the peritoneum. When surrounding organs become inflamed or infected, abscesses may form.
General symptoms of abdominal abscesses include:
- feeling unwell
- abdominal discomfort
- abdominal pain
If an infection is present, you may also develop:
- weight loss (due to loss of appetite)
Additional symptoms can occur depending on the location of the abdominal abscess.
- pain in the area containing the abscess (may be sharp or dull and achy)
- lower back pain, typical of behind the abdomen abscesses (worsens as you move your hips)
- abdominal distress (diarrhea—often a symptom of a pelvic abscess)
- pain on the left side of your abdomen (symptom of liver abscess)
Since the symptoms of an abscess are similar to symptoms of other less serious conditions, your doctor may need an imaging test for confirmation. Ultrasound is usually the first diagnostic tool used. If needed, other imaging tests such as a CT scan or MRI may be used to view the abdominal organs and tissues.
Computerized Tomography (CT) Scan
For this procedure, you will lay flat on a table. The CT scanner looks like a large circle with a hole in the middle, called a gantry. The table is positioned in the gantry. The gantry then begins to rotate around you in order to take images of your abdomen from many angles. This gives the doctor a complete view of the area. A CT scan can display ruptures, organs, abdominal growths, and foreign objects in the body.
Magnetic Resonance Imaging (MRI)
The MRI machine is a long magnetic tube. You will lie on bed that slides into the tube’s opening. The magnetic field produced by the machine surrounds your body, and aligns water molecules within your body. This allows the machine to capture clear, cross-sectional images of your abdomen.
Abscess Fluid Sample Analysis
Your doctor may choose to take a sample of fluid from the abscess and examine it for a better diagnosis. The method for obtaining a fluid sample depends on the location of the abscess.
Drainage is the first course of treating an abscess. Needle drainage is one of the methods used for this procedure. A needle is inserted through the skin and into the abscess, or into the abscess directly during surgery. The doctor pulls up the syringe to remove all of the fluid from the abscess.
Antibiotics are prescribed to prevent infection from the drainage procedure. They are also used to treat the infection causing the abscess.