From the Research
Cologuard cannot reliably distinguish hemorrhoid bleeding from other sources of blood in the stool. This is because Cologuard is a non-invasive screening test for colorectal cancer that detects both altered DNA and blood in the stool, but it does not specifically identify the source of bleeding 1. When Cologuard detects blood, it cannot determine whether that blood comes from hemorrhoids, polyps, cancer, or other conditions like inflammatory bowel disease or diverticulosis.
The test's limitations are highlighted in a 2023 study published in The American Surgeon, which found that multitarget stool DNA testing has an unacceptably low positive predictive value for colorectal cancer and precancerous lesions 1. This means that a positive Cologuard result, regardless of the cause, typically requires follow-up with a diagnostic colonoscopy to visually examine the colon and determine the exact source of bleeding.
Some factors can increase the likelihood of a false-positive result, such as successive screening, anal disorders, and the use of proton pump inhibitors 2. However, these factors do not change the fact that Cologuard cannot reliably distinguish between benign and potentially serious causes of bleeding.
Given the potential for false-positive results and the test's inability to identify the source of bleeding, it is essential to consult with a healthcare provider for proper evaluation if you are experiencing rectal bleeding and are concerned about hemorrhoids, rather than relying solely on Cologuard results. A healthcare provider can perform a physical examination, take a medical history, and order additional tests, such as a colonoscopy, to determine the cause of bleeding and develop an appropriate treatment plan.
In terms of treatment options for hemorrhoids, a 2018 study published in the American Family Physician discusses various approaches, including medical management, dietary modifications, and behavioral therapies, as well as office-based and surgical procedures 3. However, the choice of treatment depends on the severity of symptoms, the size and location of the hemorrhoids, and other individual factors, which cannot be determined by Cologuard alone.