Differential Diagnosis for Rectal Bleeding
Single Most Likely Diagnosis
- Hemorrhoids: This is often the most common cause of rectal bleeding, especially in adults. Hemorrhoids can be internal or external and are usually caused by increased pressure on the veins in the rectal area, often due to constipation, straining during bowel movements, or pregnancy.
Other Likely Diagnoses
- Diverticulosis: A condition where small, bulging pouches (diverticula) develop in the digestive tract. When these pouches bleed, they can cause rectal bleeding. Diverticulosis is common in older adults and is often associated with a low-fiber diet.
- Anal Fissures: These are small tears in the lining of the anus, which can cause pain and bleeding during and after bowel movements. Anal fissures are common and can be caused by constipation, straining during bowel movements, or spicy foods.
- Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause chronic inflammation and ulcers in the digestive tract, leading to rectal bleeding. IBD can affect anyone but is more common in younger adults.
Do Not Miss Diagnoses
- Colorectal Cancer: Although less common than other causes, colorectal cancer is a critical diagnosis to consider, especially in older adults or those with a family history of the disease. Rectal bleeding can be an early sign of colorectal cancer.
- Gastrointestinal Infections: Certain infections, such as those caused by Salmonella or Shigella, can lead to rectal bleeding. These infections are more common in travelers or individuals with compromised immune systems.
- Ischemic Colitis: Reduced blood flow to the colon can cause inflammation and bleeding. This condition is more common in older adults and those with cardiovascular disease.
Rare Diagnoses
- Angiodysplasia: A condition characterized by the presence of abnormal blood vessels in the colon, which can bleed. Angiodysplasia is rare and typically affects older adults.
- Intussusception: A condition where a part of the intestine slides into an adjacent part, potentially causing bleeding. Intussusception is rare in adults but can occur in children.
- Meckel's Diverticulum: A congenital anomaly of the small intestine that can cause bleeding, especially in children and young adults. It is a rare cause of rectal bleeding.