Culture - colonic tissue
Definition
A colonic tissue culture is a laboratory test to check for disease-causing bacteria, fungi, or viruses in a sample of tissue from the large intestine.
Alternative Names
Colonic tissue culture
Why the Test is Performed
Your doctor may order this test if you have signs or symptoms of an infection that can affect the large intestine. A culture is often done when other tests such as a stool culture could not identify the cause of infection.
How the Test is Performed
The doctor removes a piece of tissue from your large intestine during a colonoscopy. For more information on how this procedure is done, see colonoscopy.
The sample is sent to a laboratory where it is placed in a special dish containing a gel on which microoganisms can grow, and stored at a certain temperature. The laboratory team checks the sample daily to see if bacteria, viruses, or fungi have grown.
If certain microorganisms grow, more tests will be done to further identify them. This helps determine the best treatment.
How to Prepare for the Test
There is no specific preparation needed for a culture. For information on how to prepare for the procedure to remove a piece of tissue from your large intestine, see colonoscopy.
How the Test Will Feel
The laboratory culture does not involve the patient, so there is no pain.
For information on how it will feel to have a piece of large intestine tissue removed, see colonoscopy.
Risks
A colonic tissue culture poses no risks to the patient. For information on risks related to removing a sample of tissue from the large intestine, see colonoscopy.
Normal Results
A normal result means that no disease-causing organisms have grown in the laboratory dish.
Some "healthy" bacteria, called bowel flora, are normally found in the gut. The growth of such bacteria during this test does not mean there is an infection.
Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
An abnormal result means that disease-causing organisms have grown in the laboratory dish. Such organisms may include:
- Clostridium difficile bacteria
- Cytomegalovirus
- Mycobacterium tuberculosis bacteria
- Salmonella bacteria
- Shigella bacteria
These organisms may lead to infectious diarrhea or parasitic or viral infections involving the colon.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
