DIGESTIVE TRACT IN BRIEF
The digestive tract starts from the mouth and ends in the anal opening. The food we eat passed down the food pipe (esophagus) into the stomach where the initial part of digestion occurs and then passes into the small intestine where the major part of digestion and absorption of nutrients occurs.

Undigested food, water and waste products enter the colon or large intestine where a large amount of water is absorbed and the stool become more solid in consistency and enter the last portion of the colon, the rectum where it is temporarily stored until it is passed into the anal canal and excreted out of the anal opening.

BLOOD IN STOOL – OVERVIEW
When bleeding occurs in any portion of the digestive tract described above, due to any cause, the blood passes down the digestive tract and excreted out via the anal opening

Blood in stool or rectal bleeding is when you notice bright red or dark blood mixed with the stool or in the toilet bowl or staining the toilet paper.

The amount may vary from small to large; also the causes may vary from treatable conditions to a serious underlying condition

As per the Cleveland Clinic, the most common cause of blood in stool is hemorrhoids

The appearance of the blood may give a clue as to where the bleeding is coming from

Bright red blood on the surface of the stool, drops of blood in the toilet bowl or staining the toilet paper suggest the bleeding is coming from either the rectum or anal canal.

If the blood is mixed with the stool rather than occurring on its surface, the bleeding may be higher up in the digestive tract

Lastly, if the stools appear brownish black and tarry (melena) and smell bad, the bleeding may be from the upper part of the digestive tract

CAUSES OF BLOOD IN STOOL
Mild Causes
? Constipation or passage of hard and dry stools which may cause mucosal irritation and bleeding
? Anal fissure or tear in the anal mucosa
? Hemorrhoids (piles) due to swollen and congested veins in the rectum or anal canal that bleed
? Polyps or tiny growths in the mucosal lining of the large intestine or rectum that can bleed
? Angiodysplasia colon – In angiodysplasia there are several abnormal engorged blood vessels in the colon which may bleed
? False alarm – Quite commonly reddish pigment in food can give the stools a reddish color resembling blood. Some examples include beetroots, Hawaiian punch, red gelatin

Serious Causes
? Colorectal or anal cancer
? Inflammatory bowel disease – eg ulcerative colitis and Crohn’s disease
? Bleeding diverticula – Diverticula are outpouchings of the intestinal wall and bursting of a blood vessel within the diverticulum can cause rectal bleeding
? Ischemic colitis (caused by atherosclerotic disease or blood clot)
? Intestinal infections eg salmonellosis (caused by Salmonella typhi)
? Rare causes – stomach and duodenal ulcers can cause black tarry stools (melena), radiation proctitis

ASSOCIATED SYMPTOMS THAT WARRANT IMMEDIATE ATTENTION
? Severe bleeding
? Fainting
? Feeling dizzy or light headed may indicate severe blood loss
? Abdominal pain and cramps
? Cold clammy skin
? Nausea and vomiting
? Pain around the anal region
? Significant weight loss in a short span of time

DIAGNOSIS/ INVESTIGATIONS
If you notice blood in the stool, it is advisable to see a doctor to find out the underlying cause and rule out serious conditions
The doctor will conduct a detailed examination to look for possible causes of rectal bleeding and localize the site of bleeding

• Digital rectal examination – The doctor will gently insert a gloved lubricated finger into the anal canal and check for abnormalities such as hemorrhoids
• Anoscopy/ sigmoidoscopy/ colonoscopy – A thin flexible tube illuminated at one end is inserted into the anal canal. There is a camera at the end which allows the doctor to visualize any pathology and pinpoint the site of bleeding
• Full blood count – to check the general condition of the patient and degree of anemia
• If bleeding is suspected from the upper GIT, an EGD (esophagogastroduodenoscopy) is done to locate the source of bleeding.
• If no source is located in the upper GI and colorectum, then a small intestinal source must be looked for by performing video capsule endoscopy, a specialized test
• If large bowel malignancy is suspected or seen on sigmoidoscopy/ colonoscopy, further imaging such as CT or MRI scans may be needed to find the extent and spread of disease

TREATMENT OF RECTAL BLEEDING
Following investigations, once the diagnosis is confirmed, treatment will depend on the cause and severity of the condition

• Anemia due to chronic bleeding must be medically treated; if there is sudden acute blood loss, blood transfusion may be required

• Chronic constipation should be treated with diet and lifestyle changes. The diet should include adequate fiber and water. Regular exercise will
also help to prevent constipation

• Hemorrhoids – Minor lesions may be treated with warm baths and local creams to reduce irritation. For larger and more severe hemorrhoids,
more invasive treatments such as surgical excision, rubber band ligation or laser treatments are necessary

• Anal fissure may respond to conservative measures such as local creams to reduce pain and irritation and stool softeners to relieve constipation

• Bowel infections should be treated with antibiotics to eliminate the infection

• Inflammatory bowel disease is treated with medications (antiinflammatory drugs and immunosuppressants) or surgery as appropriate

• Benign polyps are treated by surgical excision (polypectomy). Angiodysplasia is treated by cauterization or surgical excision as appropriate

• Colon cancer is treated with invasive treatments such as surgery, radiation and chemotherapy

• Diverticular disease with mild symptoms may be treated by antibiotics and pain killers and bland liquid diet until the inflammation settles down. For recurrent attacks of diverticulitis, or if associated with complications such as bowel abscess, perforation, obstruction or fistula, surgery may be indicated

Reducing Risk of Rectal Bleeding
• Avoid alcohol abuse
• Avoid constipation by consuming a fiber rich diet