Three points to note regarding blood in stools: It is uncommon; it is a symptom of a larger health issue; and, you need to visit the doctor immediately. Here are the causes and the associated symptoms related to blood in stools.

Hemorrhoids: When hemorrhoids or clumps enlarge in the anal canal it causes discomfort when you have to pass stool. It makes it more difficult if the stool is hard, which causes bleeding and a lot of pain.

Bleeding in the esophagus: There is a possibility of the growth of varicose veins (enlarged veins) in the esophagus, that is, the tube that joins the mouth to the stomach. Or another possibility is the when the esophagus has tears that result in the presence of blood in the stools.

Colorectal cancer: Polyps or fleshy growth in the colon could also be a culprit. When they grow, it creates an obstruction for your stools that leads to bleeding. This benign growth can lead to cancer. Unfortunately the blood in your stool will be invisible most often.

Anal fissure: Here is where the importance of fiber comes in; when your stool is too hard or you repeatedly have bouts of diarrhea there are chances that you might develop anal fissures, which will tear or cut causing bleeding.

Diverticulitis: Diverticuli are bulging sacs in the colon caused due to pressure of the stool. When diverticuli pushes against the colon wall, causing a rupture that produces infection, this infectious disease is called diverticulitis.

Peptic ulcer: High doses of anti inflammatory drugs like asprins can cause ulcers - a condition, which is actually infection with a particular bacterium called H. pylori.

Yellow Fever: Closely associated with Africa, yellow fever is present in India too. One of the symptoms of yellow fever is blood in the stool, but the blood is black. Another symptom is black blood in your vomit.

ITP: Low platelets can result in continuous bleeding. The most evident sign is a group of blood spots. But you will witness blood in your stool and urine.

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