Also called: Stool Culture, Fecal Test

Bacteria Culture Stool Test

What Is a Bacteria Culture Stool Test?

A bacteria culture stool test checks a sample of stool (also called poop, feces, or excrement) for bacteria that cause illness.

Why Is the Test Done?

The test helps doctors see if there's a bacterial infection in the intestines, such as:

• shigella
• salmonella
• yersinia
• campylobacter
• E. coli

Sometimes, the test finds other bacteria.

Who Needs the Test?

Doctors may order this test if a child:

• has had diarrhea for several days
• has bloody diarrhea (especially if there's been an outbreak of foodborne illness in the area)
• recently traveled to certain places outside the United States

Top Things to Know

• A bacteria culture stool test checks for bacteria that can cause infections in the intestines.
• Parents usually collect the stool (poop) sample at home.
• Results can take 1–4 days.
• Your doctor can explain what the results mean and what treatment, if any, is needed.

How Is a Bacteria Culture Stool Test Done?

Unlike most other lab tests, parents might need to collect the stool sample for the test. Your doctor or lab will give instructions on how to take a stool sample.

Sometimes only one stool sample is needed but other times, samples are needed from different bowel movements. Your doctor will let you know if this is the case.

How Is the Sample Checked?

At the lab, a technician places small stool samples in sterile plastic dishes with nutrients that encourage the growth of certain bacteria. These will grow only if they're already in the stool sample.

If the bacteria grow, this means there’s an infection. The technician uses a microscope and chemical tests to identify the bacteria.

How Long Do Results Take?

Results can be back in 24–48 hours or take 3–4 days.

What Do the Test Results Mean?

If no disease-causing bacteria grow, the test is negative. This means there’s no sign of a bacterial infection. Kids then may need other tests to see what’s causing their symptoms, like a digestive problem.

What Else Should I Know?

Tell your doctor if your child recently took antibiotics because those can affect the test results. Your doctor will explain what the results mean for your child and answer any questions you have.