The severity of the condition cannot be determined simply by the presence of purplish blood in the stool. Usually, a variety of causes such as hemorrhoids, anal fissures, and rectal polyps, or even rectal tumors, can cause these symptoms to appear. If the blood in the stool is caused by hemorrhoids, the blood in the stool is brighter in color and appears red or purplish, which is not very serious and can be treated by applying hemorrhoid cream and surgically removing the blood clot. In the case of blood in the stool caused by anal fissure, the color of the bleeding will be purple or bright red and the bleeding volume is small, which can be treated by conservative means such as applying anti-inflammatory creams. For rectal polyps that cause blood in the stool, they need to be treated differently. Benign rectal polyps cause less blood in the stool and the situation is not particularly serious. If it is a malignant tumor with faster growth rate and larger size, it will cause a lot of bleeding during defecation, which is more serious and needs to be treated by surgical removal in hospital.