Skip to content
My WebMD Sign In, Sign Up

Information and Resources

Font Size

Stool Culture

How It Is Done continued...

Take the sealed container to your doctor's office or the laboratory as soon as possible. You may need to deliver your sample to the lab within a certain time. Tell your doctor if you think you may have trouble getting the sample to the lab on time.

You may need to collect several stool samples over 7 to 10 days if you have digestive symptoms after traveling outside the country.

Samples from babies and young children may be collected from diapers (if the stool is not contaminated with urine) or from a small-diameter glass tube inserted into the baby's rectum while the baby is held on an adult's lap.

Sometimes a stool sample is collected using a rectal swab that contains a preservative. The swab is inserted into the rectum, rotated gently, and then withdrawn. It is placed in a clean, dry container and sent to the lab right away.

How It Feels

Collecting a stool sample does not normally cause any discomfort.

If your doctor collects the stool sample using a cotton swab, you may feel some pressure or discomfort as the cotton swab is inserted into your rectum.

Risks

There is no chance for problems while collecting a stool sample. Be sure to wear gloves when you collect the sample and wash your hands before and after you collect the sample. This will help protect you from spreading an infection.

Results

A stool culture is done to identify bacteria, viruses, or fungi that may be causing an infection. Stool culture test results usually take 2 to 3 days. But some cultures for fungus may take weeks to get results.

Stool culture
Normal:

No disease-causing (pathogenic) bacteria, fungi, or viruses are present or grow in the culture.

Abnormal:

Bacteria (such as salmonella, shigella, campylobacter, certain types of Escherichia coli[E. coli], or Yersinia enterocolitica) grow in the culture. Fungi such as yeast are found in the stool.

If bacteria are found in the culture, sensitivity testing may be done to help choose the best treatment.

The stool also may be examined under a microscope to look for parasites such as Giardia.

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

  • Recent use of antibiotics, medicine (such as bismuth) to control diarrhea, enemas, or laxatives.
  • Recent X-ray tests using a contrast material containing barium.
  • A stool sample that is mixed with urine.
  • Not collecting a large enough sample.
  • Not getting the stool sample to the lab for testing quickly enough.

What To Think About

  • You may have an infection even if your stool culture test is normal.
  • Sensitivity testing helps your doctor choose the best treatment for the specific disease or infection.
  • A stool sample may be tested for parasites such as pinworms, roundworms, tapeworms and the protozoan Giardia that causes giardiasis. The parasites or their eggs can often be seen during an examination of the stool sample under a microscope.
  • A stool sample can also be checked for:
  • A stool analysis is a series of tests done on a sample of stool to help diagnose certain conditions affecting the digestive tract, including infection, poor absorption, or cancer. To learn more, see the topic Stool Analysis.

WebMD Medical Reference from Healthwise

Last Updated: March 07, 2012
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

Hot Topics

WebMD Video: Now Playing

Click here to wach video: Dirty Truth About Hand Washing

Which sex is the worst about washing up? Why is it so important? We’ve got the dirty truth on how and when to wash your hands.

Click here to watch video: Dirty Truth About Hand Washing

Popular Slideshows & Tools on WebMD

feet
Solutions for 19 types.
highlighted areas of the brain
How well do you know yours?
oatmeal and eggs
The best and worst for you.
dog begging at table
Foods your dog should never eat.
MS Overview
Recognizing symptoms.
mature woman with serious expression
What do you know?
chlamydia
Pictures and facts.
Healthy Snack
13 delicious options.
Take your medication
Separate fact from fiction.
lone star tick
How to identify that bite.
young woman in sun
What to watch for.
woman clutching at stomach
Do you know what's causing yours?

Women's Health Newsletter

Find out what women really need.