There is no blood in the stool, occasionally wiping the buttocks a little blood, and infrequent bleeding, no pain, the main consideration is related to dry stool, hemorrhoids and polyps and other diseases. 1. Dry stools: mainly related to improper diet, which can lead to dry stools. When defecating, too dry stools may damage the anus, triggering bleeding, which in turn leads to this symptom. 2. Hemorrhoids: especially internal hemorrhoids, can lead to symptoms of blood in the stool, and patients often do not have obvious pain symptoms. 3. polyps: polyps at the blood rich, fragile skin. When defecating, under certain pressure, can lead to polyp breakage, bleeding, and then appear to wipe the ass with blood, and no pain symptoms. The above symptoms may also be related to other diseases, and should be diagnosed and treated in time to avoid delays.