What does a positive result in a Guaiac (Hemoccult) test indicate?

A positive result in a Guaiac (Hemoccult) test indicates the presence of blood in the stool. This test is specifically designed to detect hidden (occult) blood, which may not be visible to the naked eye, thus helping in the diagnosis of conditions such as gastrointestinal bleeding, polyps, or colorectal cancer. The test uses a chemical reaction that changes color in the presence of heme, a component of hemoglobin found in red blood cells. A positive result suggests that further diagnostic evaluation is necessary to determine the source of the bleeding and guide appropriate action.