Diagnosis

White Blood Cell (Stool)

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Does this test have other names?

Stool white blood cell test, fecal leukocyte test, FLT


What is this test?

This test looks for white blood cells in your stool. It can help your doctor diagnose the cause of inflammatory diarrhea.

White blood cells, also called leukocytes, are immune system cells that can show up in the stool if you have inflammatory diarrhea. This type of diarrhea may be a symptom of an infection caused by bacteria, such as shigella, Clostridium difficile, campylobacter, or salmonella. It may also occur in inflammatory bowel disease, such as Crohn's disease or ulcerative colitis. 


Why do I need this test?

You may need this test if you have inflammatory diarrhea. Symptoms may include:

  • Many small loose or watery stools.

  • Blood or mucus in the stool.

  • Severe cramping or pain in your belly.

  • Fever.


What other tests might I have along with this test?

Your doctor may order other tests that look at the stool for:

  • Lactoferrin or calprotectin. These are substances made by certain white blood cells.

  • Parasites and their eggs (ova).

  • Toxins.

  • Blood (hemoccult test).

Your doctor may also order a stool culture. For this test, a stool sample is checked for bacteria to see if an infection is present..


What do my test results mean?

Test results may vary depending on your age, gender, health history, and other things. .Ask your doctor what your test results mean for you.

White blood cells in the stool may mean that you have inflammation in your digestive tract. But a negative result doesn't rule out a problem. Some people with these illnesses don't have white blood cells in their stool and may still need medical treatment to restore a healthy digestive system.


How is this test done?

Your doctor will give you a special container with a tightly fitting lid to place the stool sample in. If you aren't able to make a stool sample, your doctor may collect a sample by inserting a swab into your rectum. You may be able to collect a sample at home as well.


What might affect my test results?

Urine or toilet paper may contaminate the sample, affecting the results. Drinking milk can affect the results.


How do I get ready for this test?

You don't need to prepare for this test, but it's a good idea to tell the doctor about other health problems you may have. Be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illegal drugs you may use.

Author: Metcalf, Eric

Online Medical Reviewer: Chad Haldeman-Englert MD

Online Medical Reviewer: Raymond Turley Jr PA-C

Online Medical Reviewer: Tara Novick BSN MSN

Date Last Reviewed: 07/01/2025

© 2000-2026 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
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