Fecal culture
Stool culture; Culture - stool; Gastroenteritis fecal culture
A fecal culture is a lab test to find organisms in the stool (feces) that can cause gastrointestinal symptoms and disease.
A fecal occult blood test is a noninvasive test that detects the presence of hidden blood in the stool. Blood in the stool that is not visible is often the first, and in many cases the only, warning sign that a person has colorectal disease, including colon cancer.
The causative agent of typhoid fever is the bacterium Salmonella typhi. (Image courtesy of the Centers for Disease Control and Prevention.)
This picture shows the organism Yersinia enterocolitica. Yersinia organisms cause a wide range of disease but are most often associated with diarrhea or gastrointestinal symptoms. Yersinia infection is appearing with increased frequency in immunocompromised individuals. (Image courtesy of the Centers for Disease Control and Prevention.)
Campylobacter jejuni infection causes cramping, diarrhea, abdominal pain and fever within 2 to 5 days after a person has been exposed to the organism. Campylobacter jejuni is one of the most common bacterial causes of diarrhea. Most cases of Campylobacter jejuni come from handling or ingesting raw or undercooked poultry meat. Although poultry and other birds are not affected by the bacterium, other animals can be. Therefore it is possible for a person to acquire the infection from contact with infected stool of an ill cat or dog. This is what Campylobacter organisms look like through a microscope. (Image courtesy of the Centers for Disease Control and Prevention.)
Clostridium difficile is a bacterium commonly found in the intestinal tract but which, under the right circumstances, such as after or during antibiotics therapy, can be the cause of enterocolitis. (Image courtesy of the Centers for Disease Control and Prevention.)
How the Test is Performed
A stool sample is needed.
There are many ways to collect the sample.
You can collect the sample:
- On plastic wrap. Place the wrap loosely over the toilet bowl so that it is held in place by the toilet seat. Put the sample in a clean container given to you by your health care provider.
- In a test kit that supplies a special toilet tissue. Put it in a clean container given to you by your provider.
Do not mix urine, water, or toilet tissue with the sample.
For children wearing diapers:
- Line the diaper with plastic wrap.
- Position the plastic wrap so that it will prevent urine and stool from mixing. This will provide a better sample.
Return the sample to the laboratory as soon as possible. Do not include toilet paper or urine in the specimen.
In the lab, a technician places a sample of the specimen in a special dish. The dish is then filled with a gel that boosts the growth of bacteria or other germs. If there is growth, the germs are identified. The lab technician may also do more tests to determine the best treatment.
How to Prepare for the Test
You will get a collection container for the stool specimen.
How the Test will Feel
There is no discomfort.
Why the Test is Performed
The test is performed when your health care provider suspects that you may have a gastrointestinal infection. It may be done if you have severe diarrhea that does not go away or that keeps coming back.
Normal Results
There are no abnormal bacteria or other organisms in the sample.
What Abnormal Results Mean
Abnormal results may mean you have an intestinal infection. Talk to your provider about the meaning of your specific test results.
Risks
There are no risks.
Considerations
Often other stool tests are done in addition to the culture, such as:
Gram stain of stool Fecal smear Stool ova and parasites exam
References
Melia JMP, Sears CL. Infectious enteritis and proctocolitis. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 110.
Plourde AR, Beavis KG. Specimen collection and handling for diagnosis of infectious diseases. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 66.
Siddiqi HA, Rabinowitz S, Axiotis CA. Laboratory diagnosis of gastrointestinal and pancreatic disorders. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 23.
Wojewoda CM, Stempak LM. Medical bacteriology. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 57.
Version Info
Last reviewed on: 5/6/2022
Reviewed by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
