Lower GI bleeding occurs most frequently from the large intestine (colon) and rectum. The most common reasons for passage of bright red blood through the rectum as:
Local irritation by cuts (fissures) or hemorrhoids
Infections (for example with bacteria such as Shigella, Salmonella, or E. coli)
Inflammation (colitis, Crohn’s disease)
Bleeding can consist of streaks or larger clots. It can be mixed in with the stools or show as a coating outside the bowel movement.
Pediatricians and pediatric gastroenterologists see this problem quite regularly. It is estimated that GI bleeding accounts for 1% of all pediatric hospitalizations.
Straining and passage of a hard or wide stool can injure the lining of the rectum and result in bleeding. In the case of colitis, ulcers are deep enough to break the blood vessels, as the lining is inflamed and delicate. Polyps are finger-like overgrowths of the lining of the intestine and bleed when the stool rubs against them.
The treatment of lower GI bleeding depends on the cause and the location of the bleeding. Colonoscopy is the best way to determine the cause of lower GI bleeding and will be recommended if the bleeding suggests a polyp or a diagnosis of colitis is suspected. In this test, a fiber optic flexible tube with a video system allows a direct look into the rectum and can be advanced throughout the large intestine. Polyps can be removed during the colonoscopy with special snares, and biopsies taken for diagnosis or culture.
Local fissures and hemorrhoids are managed with diet modification, stool softeners and topical creams and ointments.
Polyps in children are mostly benign and usually do not recur. Follow up colonoscopy might be necessary in some cases.
Preventing constipation will help avoid the recurrence of fissures and rectal irritation.
If colitis is the reason for the bleeding, medications will be prescribed to heal the inflammation.