Fecal culture

Definition

A fecal culture is a lab test to find organisms in the stool (feces) that can cause gastrointestinal symptoms and disease.

Alternative Names

Stool culture; Culture - stool; Gastroenteritis fecal culture

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 plastic container for the toilet that the lab may give you.
• 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. Depending on the stool tests ordered, you may be given multiple collection bottles. They may have different instructions. Read everything ahead of time and make sure to follow all instructions carefully.

How the Test will Feel

There is no discomfort.

Why the Test is Performed

The test is done if you have severe, bloody diarrhea accompanied by fever or diarrhea that does not go away or 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

Multiplex polymerase chain reaction (PCR) stool panels are increasingly replacing traditional cultures.

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

Axelrad JE, Melia JMP. Infectious enteritis and proctocolitis. In: Chung RT, Rubin DT, Wilcox CM, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 12th ed. Philadelphia, PA: Elsevier; 2026:chap 112.

Fleckenstein JM. Approach to the patient with suspected enteric infection. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 262.

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.