Definition of Peritoneal fluid culture:

Peritoneal fluid culture is a laboratory test performed on a sample of peritoneal fluid to detect bacteria or fungi that cause infection (peritonitis).

Peritoneal fluid is the fluid from the peritoneal cavity, a space between the wall of the abdomen and the organs inside.

How the test is performed:

The test is performed by abdominal tap (paracentesis), a needle aspiration of the peritoneal cavity. A sample of fluid is sent to the laboratory for Gram stain and culture. The sample is examined regularly for bacterial growth.

How to prepare for the test:

Empty your bladder before your abdominal tap procedure.

How the test will feel:

A small area in your lower abdomen will be cleaned with germ-killing medicine (antiseptic). You will also receive local anesthesia. You will feel pressure as the needle is inserted. If a large amount of fluid is withdrawn, you may feel dizzy or lightheaded.

Why the test is performed:

The test is done to find out if there is an infection in the peritoneal space.

Normal Values:

Peritoneal fluid is a sterile fluid, so normally no bacteria or fungi are present.

What abnormal results mean:

The growth of any microorganism, such as bacteria or fungi, from peritoneal fluid is abnormal and indicates peritonitis.

What the risks are:

There is a small risk of the needle puncturing the bowel, bladder, or a blood vessel in the abdomen. This may result in bowel perforation, bleeding, and infection.

Special considerations:

The diagnosis of peritonitis is based on more than just the peritoneal fluid culture (which may be negative even if you have peritonitis).