What can cause a positive result in fecal occult blood test?

Several factors can cause a positive result in a fecal occult blood test (FOBT), indicating the presence of hidden blood in the stool. Here are some common causes:

1. Gastrointestinal Bleeding:

- Lower Gastrointestinal Tract Bleeding: Conditions such as hemorrhoids, anal fissures, diverticular disease, or colorectal cancer can cause bleeding in the lower digestive tract. These conditions may lead to the presence of blood in the stool.

2. Upper Gastrointestinal Tract Bleeding:

- Ulcers: Peptic ulcers in the stomach or duodenum can cause upper GI bleeding and lead to positive FOBT results.

3. Inflammatory Conditions:

- Inflammatory Bowel Disease (IBD): Conditions like ulcerative colitis and Crohn's disease can cause inflammation and damage to the lining of the colon, resulting in bleeding and positive FOBT results.

4. Medications and Supplements:

- Certain medications, such as aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), anticoagulants (blood thinners), and iron supplements, can cause irritation or ulcers in the gastrointestinal tract, leading to positive FOBT results.

5. Dietary Factors:

- Red Meat and Vegetables: Consuming large amounts of red meat or vegetables like broccoli, horseradish, or turnips can sometimes cause a false-positive FOBT result.

6. Menstruation and Pregnancy:

- Menstruation: In women, menstrual blood can contaminate the stool sample and lead to a false-positive result.

- Pregnancy: During pregnancy, the increased blood flow to the pelvic region can result in small amounts of blood in the stool.

7. Colon Polyps or Cancer:

- Precancerous Polyps: The presence of colon polyps or colorectal cancer can cause bleeding that may be detected by a FOBT.

8. Recent Colonoscopy or Biopsy:

- A colonoscopy or biopsy of the colon can cause temporary irritation and bleeding, potentially resulting in a positive FOBT result.

9. Hemorrhoids:

- Swollen or bleeding hemorrhoids can result in blood in the stool.

10. Diverticular Disease:

- Diverticular pouches in the colon can sometimes bleed and cause a positive FOBT result.

It is important to note that a positive FOBT result does not always indicate a serious underlying condition. However, it is crucial to follow up with a healthcare provider for further evaluation to determine the cause and receive appropriate medical care if necessary.