Fecal occult blood test results determine whether or not a patient has a problem in his digestive system, such as a polyp, growth or cancer in the rectum or colon, according to WebMD. The doctor carries out a fecal occult blood test to detect the presence of invisible or microscopic blood in the stool. If the test reveals microscopic blood in the feces, the patient needs to undergo additional tests to determine the source of the bleeding.Continue Reading
A patient’s stool may have blood in it because of conditions such as benign or malignant growths or polyps in the colon, intestinal infections that trigger inflammation, blood vessel abnormalities in the large intestine, diverticular disease or Meckel’s diverticulum. Hemorrhoids, ulcerative colitis, Crohn’s disease, anal fissures and ulcers may also cause blood in a patient’s stool, explains WebMD.
To perform the test, the doctor collects three stool samples, each taken a day apart, because colon cancers do not bleed consistently. The patient can also acquire fecal occult blood test kits from a pharmacy and perform the test at home, notes WebMD. The patient should not undergo the test if he has colitis, constipation, diarrhea, ulcers or hemorrhoid flare-ups. The patient should also not eat foods such as beets, radishes, red meat, cauliflower and cucumbers 48 to 72 hours before undergoing the test. A female patient on her period should also not take the test.
If blood is found in the stool, the doctor performs an upper gastrointestinal endoscopy and a colonoscopy to establish whether the blood is from the small intestine or stomach, says WebMD. If both tests are negative, the doctor performs a capsule endoscopy, where the patient swallows a small capsule that takes pictures of the gastrointestinal tract to detect the areas of bleeding.Learn more about Diagnostics & Imaging