Fecal smear is a laboratory test to check a stool sample for bacteria and other germs that can cause diseases in the digestive tract.
How the Test is Performed
A stool sample is needed.
There are many ways to collect the sample.
- You can catch the stool on plastic wrap that is loosely placed over the toilet bowl and held in place by the toilet seat. Then you put the sample in a clean container given to you by your health care provider.
- A test kit is available that supplies a special toilet tissue that you use to collect the sample. After collecting the sample, you put it in a container given to you by your health care 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.
- Put the sample in a container given to you by your health care provider.
Make sure you follow your health care provider's instructions for returning the sample. Return the sample to the laboratory as soon as possible. The sample should not include toilet tissue or urine.
The stool sample is sent to a lab where a small amount is placed on a slide. The slide is placed under a microscope and checked for the presence of bacteria, fungi, parasites, or viruses. A stain may be placed on the sample that highlights certain germs under the microscope.
How to Prepare for the Test
There is no preparation needed.
How the Test will Feel
There is no discomfort.
Why the Test is Performed
Your health care provider may order this test if you have severe diarrhea that will not go away or that keeps returning. The test result may be used to select the correct antibiotic treatment.
A normal result means there are no disease-causing germs present.
Normal value ranges may vary slightly among different laboratories. Talk to your health care provider about the meaning of your specific test results.
What Abnormal Results Mean
An abnormal result means that abnormal bacteria or other organisms have been found in the stool sample, which may be due to an infection of the digestive tract.
There are no risks associated with a fecal smear.
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Update Date 5/15/2014
Updated by: Jenifer K. Lehrer, MD, Department of Gastroenterology, Frankford-Torresdale Hospital, Aria Health System, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.