Bloody Stools

1 Bloody Stools Summary

Bloody stool, medically known as hematochezia, is a condition characterized by the presence of blood in the stool. It is also known as rectal bleeding as rectum lies just above the anus, and the belief that the blood in stool comes from the rectum.

But, as against this name, blood may come from other parts of the gastrointestinal system. The severity of the condition may vary with the person. A mild form of rectal bleeding may resolve on its own.

Mild rectal bleeding includes observation of few drops of blood in the toilet bowl or few spots on the toilet tissue. It may not require hospitalization or immediate medical evaluation.

Rectal bleeding or hematochezia may also be moderate, where the patient complains of increased frequency of bleeding. The quantity of blood lost is more than that is noted in mild hematochezia.

The blood may be dark colored and mixed with stool. It may also be lost in the form of blood clots. Severe rectal bleeding is characterized by bowel movement with large quantities of blood.

Some people may have several bowel movements, each mixed with large quantities of blood. Patients with a moderate and severe form of bloody stool often have other symptoms associated with severe blood loss from the body.

Other symptoms of blood loss include:

The blood pressure may decrease suddenly when the person changes position from sitting to lying. This condition is called as orthostatic hypotension. Moderate to a severe form of bleeding may require hospitalization for treatment.

As mentioned earlier, bleeding may occur from any part of the gastrointestinal tract.

Bleeding may occur from rectum or anus, and this is characterized by the bright red color of the blood. This may or may not be mixed with stools. This is often noticed after passing stool.
If the bleeding occurs from the colon, the blood is dark red in color and mixed with feces. In some rare cases, the blood may not be mixed with stool.

Bleeding that originates from the stomach or small intestine mixes blood with stool and changes the color of feces to black or plum colored. This condition requires medical attention as it involves lots of bleeding.

Bloody stool may be caused by multiple factors, including:

Diagnostic tests suggested for bloody stools depend on the possible cause of bloody stools. Medical history and physical examination provide important clues regarding the probable causes.

Sigmoidoscopy, colonoscopy, and CT colonography are the commonly suggested methods for identifying the underlying cause of blood in stools. In some disorders, the bleeding may be limited to a trickle and is difficult to see.

In such cases, fecal occult blood test helps to determine the amount of blood in the stool. It is usually recommended when the person has other symptoms suggestive of disorders of the gastrointestinal system.

Treatment methods vary according to the actual cause of the condition. Stool softeners are suggested to reduce bleeding in people with hemorrhoids. Sitz bath is also useful in reducing pain and prevent bleeding. Ulcers are treated with acid-reducing medications, while antibiotics are used in case of inflammatory bowel disease and infections.

2 Causes

There are many possible causes for the presence of blood in the stool.

Some of the common causes are:

Hemorrhoids – or piles, as it is popularly known as, are characterized by the presence of swellings in anus and rectum. Bleeding after stool is the most common symptom of hemorrhoids. Other symptoms include mucus discharge, pain, irritation and itching in the anal region. 

Anal fissure – a tear in the anal skin is referred is known as anal fissure. This tear is usually small but is very painful. Anal fissures cause mild bleeding which is noted after the passing of stool. The blood is fresh and bright red and stops soon.

Diverticula – diverticula refers to small pouches that project from the wall of the gut. It is more commonly found in the colon but can be found in other parts of the gut as well. Some of the diverticula may bleed causing abrupt bleeding through the anus. This bleeding is usually painless, though blood loss may be severe. It is associated with other symptoms like abdominal pain and changes in bowel movement.

Crohn’s disease – it is an inflammatory condition of the gut that flares up occasionally. Symptoms of Crohn’s disease depends on the severity and location of inflammation in the gut. Bloody stools and abdominal pain are the most common symptoms of the condition.

Colitis – inflammation of colon leads to bleeding. Ulcerative colitis is a condition characterized by inflammation of colon and rectum. Bloody diarrhea is a common symptom of the condition as bleeding occurs from the ulcers present in the inner wall of the colon.

Polyps – small outgrowths that form on the inner wall of colon and rectum are known as polyps. These growths are benign and are more commonly found in older people. A polyp may bleed sometimes resulting in the bloody stool.

Cancer – rectal bleeding is a common symptom of colon and rectal cancer. Bleeding is not visible in most of the cases and is associated with other symptoms. People with cancer may have unexplained weight loss, anemia, diarrhea or constipation.

Angiodysplasia – blood vessels in the inner lining of the colon may become enlarged leading to angiodysplasia. This may lead to painless bleeding and may range from bright red to plum-colored feces.

Abnormalities of gut – rectal bleeding may be caused by abnormalities of the gut like twisting or volvulus.


Other abnormalities include:

  • Intussusception where one part is sucked into another region.
  • Meckel's diverticulum, a congenital problem characterized by an extra bulge in small intestine
  • Hirschsprung's disease, where the muscles of bowel cannot move the feces
  • Abnormal development of blood vessel in the gut

Ulcers in stomach – bleeding of ulcers in stomach and duodenum lead to dark-colored stools.

Gut infections – infections of the gut may lead to inflammation, which leads to bloody diarrhea.

Some less common causes of bloody stools are sexually transmitted infections and use of anticoagulant drugs.

3 Diagnosis and Treatment

Medical history, associated symptoms and physical examination of the patient aid in identifying the possible cause of bleeding. Physical examination may include evaluation of anus and rectum.

This is also done with the help of proctoscope which is useful in checking deeper into the gut. Anal fissures and hemorrhoids are diagnosed with this method.

Other tests and investigations are based on the suspected cause of bleeding in different parts of the gut. Three tests are usually suggested for confirmatory diagnosis – sigmoidoscopy, colonoscopy, virtual colonoscopy or CT colonography.

Colonoscopy – in this procedure a colonoscope is inserted into the anus and passed to the colon. It is used to visualize the parts of large intestine till the meeting point with the small intestine. The fiber optic channels in the colonoscope help to visualize the inner parts of the gut. It can also be used to take a small sample of the inner lining of the colon for biopsy.

Sigmoidoscopy – this procedure uses a shorter form of colonoscopy that with a light source attached to it. This is usually used in cases where the bleeding is suspected to occur from lower parts of the colon, particularly the part that is joined to the rectum. The sigmoidoscope is inserted through the anus and passed to sigmoid colon and rectum.

Virtual colonoscopy – in this procedure a tube is passed into rectum which helps to push gas into the bowel to open it. CT scan of the bowel is the next step in this method.

Disorders in which bleeding is very less use a fecal occult blood test to evaluate bleeding. This procedure can only detect the blood cells in stool, but cannot detect the location of bleeding. Other imaging techniques like MRI, X-ray, and CT scan help in visualizing the flow of blood in the gastrointestinal system.

Treatment of bloody stool varies with the underlying cause of the problem. Stool softeners are recommended for people with hemorrhoids as it makes the movement of stool easier. Sitz bath is suggested to relieve pain and to prevent bleeding.

Bleeding from ulcers is treated with acid-reducing drugs. Inflammatory bowel disease is treated with immunosuppressant medications, while antibiotics are the choice for controlling infections.

Surgery is suggested for removing abnormalities in vein and blockages. This is usually recommended when bleeding does not resolve on its own or with conventional treatment.

Those who have heavy blood loss due to bleeding may develop anemia and require a blood transfusion. This procedure is essential to replace the lost blood cells in the body.

Benign polyps may not require much treatment, and periodic monitoring is suggested. Polyps that are cancerous are treated with radiation therapy and chemotherapy.

Bloody stools can be prevented by keeping oneself well hydrated and by eating fiber-rich foods. This helps to soften the stool, aiding easy movement of feces. Raspberries, beans, artichokes, and whole grains are rich in fiber and can prevent this symptom.

But the choice of food should be done only after discussing with the doctor. This is particularly important in the case of people who have inflammatory bowel disease, where certain foods may irritate bowel and lead to inflammation.

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