White Blood Cell (WBC) in Stool

This test looks for white blood cells in a sample of your stool (poop). White blood cells are also called leukocytes, so this test is sometimes called a leukocytes in stool test. White blood cells are part of your immune system.

They help your body fight off infections and other diseases. White blood cells in your stool are usually a sign that you have an infection or other condition in your digestive system that's causing inflammation. A white blood cell in stool test is used if you have diarrhea that could be caused by inflammation.

Diarrhea from inflammation is severe and lasts for more than a couple days. It can include blood in stool, abdominal (belly) pain, and fever. It may be caused by: Certain bacterial infections, such as: Clostridium difficile (C. diff).

This infection mostly happens after taking antibiotics that kill the 'good germs' that keep C. diff bacteria from growing in your body.; Some types of bacteria that cause 'food poisoning,' including: Salmonella. Most infections come from contaminated food, but you can get salmonella from infected animals, especially reptiles and birds.; Shigella. Infection with shigella is called shigellosis.

You can get it from food and touching contaminated surfaces and then touching your mouth.; Campylobacter. Infection can happen from food and contact with dog and cat feces (poop).; ; ; Inflammatory bowel disease (IBD), which includes: Ulcerative colitis; Crohn's disease; ; A parasite (Entamoeba histolytica) which causes a disease called 'amebiasis.' Amebiasis is most common in tropical places with poor sanitary conditions.; A white blood cell in stool test can't diagnose the exact condition that's causing diarrhea. But it can help narrow down the possible causes to conditions that either do or don't involve inflammation.

Why this test is done

Most diarrhea goes away on its own after a day or two, and your health care provider doesn't need to find the cause. But you may need a white blood cell in stool test and other tests if you have symptoms of diarrhea from inflammation that don't improve after a few days.

Knowing the cause of your diarrhea helps your provider choose the right treatment. That's important because ongoing diarrhea can lead to serious health problems, including dehydration and electrolyte imbalances.

See your provider right away if you have:

• Signs of dehydration, including dry mouth, dark urine (pee), fatigue, or dizziness
• Diarrhea for more than 2 days, or for more than 24 hours in a young child or infant
• A fever of 102 degrees or higher
• Severe pain in the abdomen (belly) or rectum
• Stool that is black and tarry or contains blood or pus
• In adults: frequent vomiting or diarrhea 6 or more times in 24 hours

How to prepare

Certain medicines and foods may affect the test results. Ask your provider if there are any specific things you need to avoid before the test.

Sample type

Stool

Other names for this test

leukocytes in stool, stool WBC, fecal WBC, fecal leukocyte test, FLT, FGST, fecal leukoctye gram stain screen