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.
Culture - peritoneal fluid
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 If a large amount of fluid is withdrawn, you may feel dizzy or lightheaded.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.
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.
The diagnosis of peritonitis is based on more than just the peritoneal fluid culture (which may be negative even if you have peritonitis).
Garcia-Tsao G. Cirrhosis and its sequelae. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 157.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.