Fecal Immunochemical Test

• The Fecal Immunochemical Test (FIT) is a non-invasive screening method for detecting hidden blood in stool.
• Its primary purpose is to aid in the early detection of colorectal cancer and precancerous polyps.
• FIT works by specifically identifying human hemoglobin, making it more accurate than older tests.
• A positive FIT result indicates the presence of blood and necessitates further investigation, typically a colonoscopy.
• Regular screening with FIT can significantly improve outcomes by catching potential issues at an early, more treatable stage.

What is a Fecal Immunochemical Test (FIT) and its Purpose?

A Fecal Immunochemical Test (FIT) is a laboratory test that checks for occult (hidden) blood in a stool sample. Unlike older tests that detect both human and animal blood, FIT specifically targets human hemoglobin, a protein found in red blood cells. This specificity reduces the likelihood of false positives due to dietary factors, as it is not affected by foods like red meat or certain vegetables.

The primary Purpose of Fecal Immunochemical Test is to screen for colorectal cancer and precancerous polyps. These growths can bleed intermittently, and while the blood may not be visible to the naked eye, FIT can detect even tiny amounts. Early detection is vital for successful treatment, as colorectal cancer is often treatable when found in its initial stages. According to the Centers for Disease Control and Prevention (CDC), regular screening can prevent colorectal cancer or find it early, when treatment is most effective.

How Does FIT Testing Work?

The Fecal Immunochemical Test (FIT) is a simple, non-invasive test performed at home. Patients receive a collection kit from their healthcare provider, which typically includes a collection device and instructions. The process involves collecting a small stool sample, usually from a single bowel movement, and returning it to the lab for analysis. Because FIT specifically detects human hemoglobin, there are generally no dietary or medication restrictions required before taking the test, making it convenient for many individuals.

Once the sample reaches the laboratory, it is analyzed using antibodies that bind to human hemoglobin. If hemoglobin is present in the sample, it reacts with these antibodies, leading to a detectable signal. The level of hemoglobin detected determines whether the result is positive or negative. This method offers several advantages:

• It is highly specific to human blood, reducing false positives.
• It is non-invasive and can be done in the privacy of one’s home.
• No special diet or medication adjustments are typically required.
• It is a cost-effective screening option for large populations.

Fecal Immunochemical Test Results Explained

Understanding Fecal Immunochemical Test results explained is crucial for appropriate follow-up. A negative FIT result indicates that no human hemoglobin was detected in the stool sample above a certain threshold. While this suggests a low likelihood of significant bleeding from the lower gastrointestinal tract at the time of the test, it does not completely rule out the presence of polyps or cancer, as these may not bleed continuously. Therefore, regular screening at recommended intervals is still important.

A positive FIT result means that human hemoglobin was detected in the stool sample. It is important to understand that a positive FIT does not diagnose cancer. Instead, it indicates the presence of bleeding, which could be caused by various conditions, including:

• Colorectal polyps (benign or precancerous)
• Colorectal cancer
• Hemorrhoids
• Diverticulosis
• Inflammatory bowel disease

If a FIT result is positive, the next step is typically a diagnostic colonoscopy. A colonoscopy allows a gastroenterologist to visually inspect the entire colon and rectum, identify the source of bleeding, and remove any polyps or take biopsies of suspicious areas. Discussing your FIT results with your healthcare provider is essential to determine the most appropriate next steps for your individual health needs.