Rectal bleeding

Rectal bleeding is a common symptom that can occur in various diseases. It is very important to determine the exact cause of the bleeding, as the treatment strategy depends on the underlying condition. Some causes, such as hemorrhoids or anal fissures, are usually treated conservatively. However, others, such as colorectal cancer or inflammatory bowel disease, require urgent diagnosis and treatment.

What are the signs of rectal bleeding?

• You notice fresh blood on toilet paper;
• You notice blood in the toilet after a bowel movement;
• You notice red streaks on the surface of your stool.

The most common causes of rectal bleeding:

• Hemorrhoids: these are the dilation and downward prolapse of blood vessels (hemorrhoidal nodes) in the anal canal. Hemorrhoids can be internal (nodes form inside the rectum) or external (nodes form around the anus). For many people, symptoms improve with home treatment and lifestyle changes;
• Anal fissure: a small tear in the skin or mucous membrane of the anus. It often causes pain and rectal bleeding, especially during bowel movements. This condition can occur in people of any age, but it is more commonly diagnosed in infants and during pregnancy;
• Inflammatory bowel disease: most commonly causes chronic inflammation of the intestinal lining—in both the small and large intestines. Crohn’s disease most often affects the small intestine, while ulcerative colitis affects the large intestine.
• Inflammatory bowel disease causes chronic abdominal pain and diarrhea, and in severe cases, it can lead to bleeding;
• Diverticulitis: This is an acute inflammation of one or more diverticula, accompanied by erosion or localized necrosis of the diverticulum wall, which can lead to micro- or macroperforation of the diverticulum wall and cause bleeding.

Other possible causes:

• Infectious colitis: Some bacterial infections, such as E. coli and C. diff, can cause hemorrhagic colitis—bleeding from the large intestine. This typically presents as bloody diarrhea. If your symptoms last longer than a couple of days, see a specialist;
• Sexually transmitted infections (STIs): Certain common STIs can cause inflammation and bleeding from the rectum, including gonorrhea, chlamydia, and syphilis. Most STIs require specific treatment, so it’s important to get them diagnosed;
• Peptic ulcer: These most commonly develop in the stomach or duodenum. They occur when stomach acid damages the protective lining, creating open sores. An ulcer causes a burning or gnawing pain in the stomach and may bleed. Bleeding in the upper gastrointestinal tract takes longer to occur, so the blood may be dark, black, and tarry;
• Colonic polyps and colon cancer: Polyps are common, and larger ones may bleed. Sometimes, polyps can develop into cancer, which may bleed more frequently.

Can straining too hard during a bowel movement cause rectal bleeding?

Yes. Constipation and straining during bowel movements can cause rectal bleeding. Straining increases pressure in the rectal area, which can cause hemorrhoids to enlarge and result in traces of blood. In addition, very hard stools can damage the mucous membrane or cause anal fissures, which also lead to bleeding.

How is rectal bleeding diagnosed?   

• Medical history and physical examination: To diagnose rectal bleeding, the doctor will ask about your symptoms, their onset, progression, family history, and risk factors, and will perform a rectal examination;
• Digital rectal exam: a finger examination of the rectum to assess tone and integrity;
• Anoscopy: a procedure during which the doctor examines the mucous membrane of the anus and rectum;
• Colonoscopy: an endoscopic examination performed when colorectal cancer, ulcerative colitis, Crohn’s disease, or diverticulosis is suspected;
• Stool test. The doctor may perform a stool test to check for active bleeding, traces of occult blood, or signs of inflammation. They may also check for specific infections;
• Fibrogastroduodenoscopy (FGDS): This is a procedure in which the digestive system is examined using an endoscope. Using the endoscope, the doctor looks for signs of inflammation and suspicious areas or growths; if necessary, the doctor may take small tissue samples, which are sent to a laboratory where pathologists determine the exact nature of the pathology.

What is the treatment for rectal bleeding?

In most cases, treatment will depend on the underlying cause. If rectal bleeding is caused by an anal fissure or hemorrhoids, a consultation with a specialist is recommended.

When should I be concerned and see a doctor about rectal bleeding?

Rectal bleeding is a reason to see a doctor. It may be a symptom of a more serious condition that requires treatment. If the bleeding is heavy or you notice blood clots after a bowel movement, go to the nearest medical facility.