The stool guaiac test looks for hidden (occult) blood in a stool sample. It can find blood even if you cannot see it yourself. It is the most common type of fecal occult blood test (FOBT). Guaiac is a substance from a plant that is used to coat the FOBT test cards. Usually, you collect a small sample of stool at home.
How do you do a guaiac test?
- Collect a stool sample from three consecutive bowel movements.
- Smear a small amount of the stool on a card that has been provided in the kit.
- Mail the card to a laboratory for testing.
- Ensure that you follow the manufacturer's instructions in order to get accurate results.
What is the primary purpose of guaiac test?
What is the primary purpose of a guaiac slide tests and what specimen is used for this test? The stool guaiac test looks for hidden (occult) blood in a stool sample. It can find blood even if you cannot see it yourself. It is the most common type of fecal occult blood test (FOBT). Guaiac is a substance from a plant that is used to coat the FOBT ...
How to do guaiac test?
The steps to this test typically are as follows:
- Flush the toilet before your bowel movement.
- If provided, place paper in the toilet to catch bowel movement.
- Use the brush provided by the kit to brush the surface of your stool and dip into toilet water.
- Touch brush with sample on the space indicated on test paper.
How often to have smear test?
Women should start Pap smear screening at age 21. Between the ages of 21-29, women whose Pap smears are normal only need it repeated every three years. Women ages 30 and over should have testing for the human papillomavirus (HPV) with their Pap smear. HPV is the cause of cervical cancer.
What would a positive guaiac test indicate?
A fecal occult blood test uses chemicals to find out if there is blood in a sample of feces. If your test is negative, your result is normal. If your test is positive, you had blood from your digestive tract in your stool sample.
What is guaiac positive stool?
For the FOBT, a positive test result indicates that abnormal bleeding is occurring somewhere in the digestive tract. As we've stated, this blood loss could be due to a number of things besides cancer, so if the test finds blood, a colonoscopy will be needed to look for the source.
What color is a positive guaiac test?
Background: In guaiac-based faecal occult blood tests (FOBT), blue colours are considered positive. Blue-green colours should also be considered positive. Distinct green colours are said to be due to bile and it is stated that these should be interpreted as negative.
How is stool guaiac test done?
Guaiac fecal occult blood test (gFOBT). You collect a stool sample from each of two or three bowel movements in a clean container, usually taken on consecutive days, and then use an applicator stick to apply a smear of stool to a specific area of a card.
What is the most common cause of occult blood in stool?
Some of the more common causes include colon cancer, esophagitis, peptic ulcers, gastritis, inflammatory bowel disease, vascular ectasias, portal hypertensive gastropathy, gastric antral vascular ectasias, and small bowel tumors (eg, GI stromal cell tumor, lymphoma, carcinoid, adenocarcinoma, or polyp).
What are the foods to avoid during the stool guaiac test Why?
Some foods can affect test results. Follow instructions about not eating certain foods before the test....These may include:Red meat.Cantaloupe.Uncooked broccoli.Turnip.Radish.Horseradish.
How do you read a guaiac test?
A testing solution is put on the cards and the guaiac causes the stool sample to change color. If there is blood in the stool, the color changes very quickly. Blood in the stool may be a sign of colorectal cancer or other problems, such as polyps, ulcers, or hemorrhoids.
What does positive occult stool mean?
A positive fecal occult blood test means that blood has been found in the stool. Your doctor will have to determine the source of the bleeding, either by doing a colonoscopy or by doing an examination to determine if the bleeding is coming from the stomach or small intestine.
What happens if blood is found in stool sample?
You will need further tests if there is blood found in your poo. Your doctor might call this FIT positive. This doesn't mean that you have cancer. Blood in your poo can be caused by cancer or by other medical conditions.
What should you avoid before a stool test?
Here's how to do the test right: Watch what you eat. Two days before and the day of the fecal occult blood test, cut out all red meat, beets, broccoli, cantaloupe, carrots, cauliflower, cucumbers, grapefruit, horseradish, mushrooms, radishes, and turnips, which can all trigger false alarms.
What can cause a positive stool test?
Blood may show up in your poop because of one or more of the following conditions: Growths or polyps of the colon. Hemorrhoids (swollen blood vessels near the anus and lower rectum that can rupture, causing bleeding) Anal fissures (splits or cracks in the lining of the anal opening)
What are the symptoms of occult blood?
Symptoms of OGIB include a change in the color of stools to black-tarry or even maroon, a drop in red blood cells (anemia) and low blood pressure, on occasion. Patients with OGIB may be admitted to the hospital several times for blood transfusions.
Does Iron Make stool guaiac positive?
Most studies show that oral ingestion of iron does not cause a positive stool guaiac reaction. However, all in vitro studies show that iron does cause a positive guaiac reaction and some in vivo studies have shown a positive stool guaiac reaction in response to oral iron.
What causes false-positive stool occult blood?
False-positive results have been associated with red or rare meat as well as raw fruits and vegetables, including but not limited to horseradish, raw turnips, cantaloupe, broccoli, cauliflower, parsnips, and red radishes.
What does a stool culture test for?
A stool culture is used to detect the presence of disease-causing (pathogenic) bacteria and help diagnose an infection of the digestive system (gastrointestinal, GI tract).
How can you tell if Hemoccult is positive?
A distinct green color (no blue) appearing on or at the edge of the smear within 60 seconds after adding Hemoccult SENSA Developer, should be interpreted as negative for occult blood. A blue or blue-green color should be interpreted as positive for occult blood.
What is the test for occult blood?
Guaiac fecal occult blood test. This test can detect small amounts of blood in stool. It requires abstaining from red meat and certain medications for a number of days before. An FOBT is more specific to finding blood from further up the digestive tract, such as the stomach. Looks for blood in stool.
How to smear stool sample?
Use a wooden applicator or a brush to smear a thin film of the stool sample onto one of the slots in the test card or slide.
What does a positive FOBT test mean?
For the FOBT, a positive test result indicates that abnormal bleeding is occurring somewhere in the digestive tract. As we’ve stated, this blood loss could be due to a number of things besides cancer, so if the test finds blood, a colonoscopy will be needed to look for the source.
How long before a blood test can you eat red meat?
Red meats for three days before testing, as the components of blood in the meat may cause the test to show positive
What is a guaiac test?
It can find blood even if you cannot see it yourself. It is the most common type of fecal occult blood test (FOBT). Guaiac is a substance from a plant that is used to coat the FOBT test cards.
What causes a positive stool guaiac test?
Hemorrhoids. Crohn disease or ulcerative colitis. Peptic ulcer. Other causes of positive test may include: Nosebleed. Coughing up blood and then swallowing it. If the stool guaiac results come back positive for blood in the stool, your doctor will likely order other tests, often including a colonoscopy.
Can stool guaiac test detect cancer?
The stool guaiac test does not diagnose cancer. Screening tests such as colonoscopy can help detect cancer. The stool guaiac test and other screenings can catch colon cancer early, when it is easier to treat. Risks.
Does Guaiac react with heme?
Guaiac reacts not only with heme but also with chemicals that are found in plants. People who are taking the test should abstain from iron supplements, red meat, certain vegetables, vitamin C, and citrus fruit for several days before the test.
Can you take a guaiac test with heme?
The chemical guaiac reacts not only with heme but also with chemicals found in plants. People who are taking the test are advised to abstain from consuming iron supplements, red meat, certain vegetables, vitamin C, and citrus fruit for several days before the test. The test is completely noninvasive and only requires you take a sample of your stool after you use the bathroom. You will need to take samples from three separate bowel movements. After you follow the instructions with your kit you will mail the sample envelope to the lab to be analyzed.
Can FIT and GFOBT detect blood?
Both the FIT and gFOBT tests detect hidden blood in stool samples that are collected at home. However, the nature of the laboratory analysis is distinct between the two along with the dietary preparation before the test.
How often is a guaiac blood test done?
The guaiac-based fecal occult blood test (gFOBT) uses the chemical guaiac to detect blood in the stool. It is done once a year. For this test, you receive a test kit from your health care provider. At home, you use a stick or brush to obtain a small amount of stool.
What is the test for polyps in the colon?
Colonoscopy. This is similar to flexible sigmoidoscopy, except the doctor uses a longer, thin, flexible, lighted tube to check for polyps or cancer inside the rectum and the entire colon. During the test, the doctor can find and remove most polyps and some cancers. Colonoscopy also is used as a follow-up test if anything unusual is found ...
What tests can be used to detect polyps?
Several screening tests can be used to find polyps or colorectal cancer. The Task Force outlines the following colorectal cancer screening strategies. It is important to know that if your test result is positive or abnormal on some screening tests (stool tests, flexible sigmoidoscopy, and CT colonography), a colonoscopy test is needed ...
How to know if a screening test is right for you?
How Do I Know Which Screening Test Is Right for Me? 1 Your preferences. 2 Your medical condition. 3 The likelihood that you will get the test. 4 The resources available for testing and follow-up.
How often is a FIT DNA test done?
For this test, you collect an entire bowel movement and send it to a lab, where it is checked for cancer cells. It is done once every three years.
Advantages
Disadvantages
- Cannot identify polyps; can only detect signs of cancer
- Will need a colonoscopy if test is positive
- Patients may find test unpleasant
- Requires strict adherence to the test protocol for the test to be accurate (restricted diet and multiple days of stool collection)
Will My Insurance Cover It?
- Medicare covers FOBT once a year for individuals 45 and over. Most other insurances cover the test too; talk to your carrier.
The Facts
- The guaiac fecal occult blood test (FOBT) is used to find occult blood (or blood that can’t be seen with the naked eye) in stool. The idea behind this test is that blood vessels at the surface of larger polyps or cancers are often fragile and easily damaged by passing stool. The damaged blood vessels usually release a small amount of blood into the...
The Prep
- Some foods or drugs can affect the outcome of the FOBT, so your doctor may suggest that you avoid the following before this test: 1. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil), naproxen (Aleve) or aspirin (more than one adult aspirin per day), for seven days before testing 2. Vitamin C in excess of 250 mg daily from either supplements or citrus fruits an…
The Procedure
- Begin with all of your supplies ready and in one place. Supplies will include a test kit, test cards, either a brush or wooden applicator and a mailing envelope. The kit will give you detailed instructions on how to collect the stool. The instructions below can be used as a guide, but your kit instructions could be a little different, so always follow those instructions first. First, you’ll ne…
The Big 'What If…'
- For the FOBT, a positive test result indicates that abnormal bleeding is occurring somewhere in the digestive tract. As we’ve stated, this blood loss could be due to a number of things besides cancer, so if the test finds blood, a colonoscopy will be needed to look for the source.