Understanding Fecal Occult Blood Test (FIT) and Related Markers

The Fecal Occult Blood Test (FIT) is a common screening tool used to detect hidden blood in the stool, which can be an early sign of bowel cancer. Understanding how to read this test and its related markers can help you and your healthcare provider make informed decisions about your health.

What is the Fecal Occult Blood Test (FIT)?

The FIT is a non-invasive test that checks for hidden (occult) blood in the stool, which is not visible to the naked eye. It is often used as part of routine screening for bowel cancer. The test measures the amount of hemoglobin (a protein in red blood cells) in the stool sample. A typical adult range for FIT is 0 to 10 µg Hb/g. A result is typically reported as positive or negative around a 10 µg Hb/g threshold.

Why is the FIT important?

Detecting blood in the stool can be an important indicator of potential issues in the digestive tract. Blood in the stool may be caused by a variety of conditions, including hemorrhoids, ulcers, or more serious conditions like bowel cancer. Early detection through FIT can lead to earlier diagnosis and treatment, potentially improving outcomes.

How to interpret FIT results

• Negative Result: A negative result means that no blood was detected in your stool sample, or the amount of blood is below the 10 µg Hb/g threshold. This is generally considered a normal result.
• Positive Result: A positive result indicates that blood was detected in your stool sample above the 10 µg Hb/g threshold. This does not necessarily mean you have bowel cancer, but it does warrant further investigation by a healthcare provider.

Related markers and their significance

While FIT is primarily used to detect hidden blood in the stool, other related markers might be assessed to provide a more comprehensive picture of your digestive health. These may include tests for inflammatory markers or other stool tests. However, FIT remains a key component in bowel cancer screening due to its specificity for detecting blood.

Frequently asked questions

What should I do if my FIT result is positive? If your FIT result is positive, it is important to follow up with your healthcare provider. They may recommend additional tests, such as a colonoscopy, to determine the source of bleeding.

Can medications affect my FIT results? Certain medications, particularly those that can cause gastrointestinal bleeding like nonsteroidal anti-inflammatory drugs (NSAIDs), may affect your FIT results. Inform your healthcare provider about any medications you are taking before the test.

How often should I have a FIT? The frequency of FIT screening can depend on your age, risk factors, and healthcare provider's recommendations. Generally, it is recommended annually for individuals over a certain age, but your provider will give the best advice for your specific situation.

When to see a doctor

You should see a doctor if you receive a positive FIT result, experience unexplained changes in bowel habits, or notice visible blood in your stool. These could be signs of underlying conditions that require medical evaluation.

Remember, this information is intended to help you understand your test results. Always consult with your healthcare provider for medical advice and decisions regarding your health.