Blood in the Stool (Rectal Bleeding) (cont.)

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What diseases and conditions can cause blood in the stool (rectal bleeding)?

Many diseases and conditions can cause rectal bleeding. Common causes include:

  • Anal fissures
  • Hemorrhoids
  • Cancers and polyps of the rectum and colon
  • Diverticulosis
  • Abnormal blood vessels in the lining of the intestines (angiodysplasia)
  • Ulcerative colitis
  • Ulcerative proctitis
  • Crohn's colitis
  • Infectious colitis
  • Ischemic colitis
  • Meckel's diverticula

As discussed previously, it also is possible for "rectal bleeding" to be coming from the stomach and duodenum, primarily from ulcers, cancers, and angiodysplasias.

Anal fissures

An anal fissure is a fairly common, painful condition in which the lining of the anal canal is torn. An anal fissure usually is caused by constipation or a forceful bowel movement, though a tight anal muscle or physical trauma also may be contributing factors. Once the skin is torn, each subsequent bowel movement can be painful, and the pain often is severe. The amount of bleeding that occurs with an anal fissure is small and usually is noticed in the toilet bowl or on the toilet paper as bright red in color. The symptoms of an anal fissure are commonly mistaken for hemorrhoids, but hemorrhoids generally do not cause pain with bowel movements.

Hemorrhoids

Hemorrhoids are masses or clumps ("cushions") of tissue within the anal canal that contain blood vessels. Although most people think hemorrhoids are abnormal, they are present in everyone. It is only when the hemorrhoidal cushions enlarge that hemorrhoids become susceptible to trauma from passing stool cause problems (such as bleeding or anal discomfort) and be considered abnormal or a disease. Like anal fissures, bleeding from hemorrhoids usually is mild and does not cause anemia or low blood pressure. Rarely, a person may develop iron deficiency anemia as a result of repeated hemorrhoidal bleeding over several months to years, especially if the dietary intake of iron is low.

Picture of the formation of hemorrhoids
Picture of the formation of hemorrhoids
Medically Reviewed by a Doctor on 10/29/2015


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Blood in the Stool - Experience Question: Please describe your experience with blood in the stool.
Blood in the Stool - Causes Question: What was the cause of blood in your stool?
Blood in the Stool - Diagnosis Question: What was the diagnosis of blood in the stool?
Blood in the Stool - Treatment Question: Depending on the cause, what was the treatment for blood in the stool?
Blood in the Stool - Hemorrhoids Question: Please describe your experience with hemorrhoids and blood in your stool.
Blood in the Stool - Anal Fissures Question: Please describe your experience with anal fissures and rectal bleeding.
Blood in the Stool - Diseases Causes Question: Which one of these were the cause of your case of rectal bleeding, and please describe your experience.
Blood in the Stool - Infection Question: What infection caused your case of rectal bleeding, and how was it treated?
Blood in the Stool - Ulcers or Gastritis Question: Was it ulcers or gastritis that caused your case of rectal bleeding, and how was it treated?
Blood in the Stool - Esophageal Bleeding Question: Please describe your experience with rectal bleeding and esophageal bleeding.
Blood in the Stool - Rare Causes Question: If not mentioned previously, what caused your case of rectal bleeding?
Blood in the Stool - Associated Symptoms Question: What symptoms did you have that occurred with rectal bleeding?