Rectal bleeding refers to bright or dark red blood coming from the rectum during defecation or passing gas.
Causes
Common (benign): Haemorrhoids, anal fissure, rectal polyp, diverticular disease.
More serious: Colorectal cancer, inflammatory bowel disease (Crohn's, ulcerative colitis), angiodysplasia.
Red Flags
Over 50 years old, family history of colorectal cancer, bleeding accompanied by weight loss, night sweats and fatigue; dark (melaena) or clotted blood; requires urgent assessment.
Diagnosis
Evaluated with rectal examination, anoscopy, sigmoidoscopy and colonoscopy. CT colonoscopy or CT angiography may be performed if necessary.
Important Warning
Rectal bleeding should never be taken lightly; specialist advice should always be sought, especially in recurring or large-volume cases.