Differential Diagnosis for Bright Red Blood in Stool
Single most likely diagnosis
- Hemorrhoids: This is the most common cause of bright red blood in stool, especially in young adults. The blood is typically seen on the toilet paper or dripping into the toilet bowl after a bowel movement.
Other Likely diagnoses
- Anal Fissure: A tear in the lining of the anus can cause bright red blood, often accompanied by pain during and after bowel movements.
- Diverticulosis: Although more common in older adults, diverticulosis can occur in younger individuals and may cause bright red blood in the stool, usually without other symptoms.
- Inflammatory Bowel Disease (IBD): Conditions like ulcerative colitis or Crohn's disease can cause rectal bleeding, among other symptoms such as diarrhea, abdominal pain, and weight loss.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
- Colon Cancer: Although rare in young adults, colon cancer can present with rectal bleeding and should always be considered, especially if there's a family history or other alarming symptoms like significant weight loss or anemia.
- Gastrointestinal Angiodysplasia: Vascular malformations in the gut can cause bleeding, which may be bright red if it's coming from the lower GI tract.
- Infectious Colitis: Certain infections can cause inflammation and bleeding in the colon, which might present with bright red blood in the stool, along with diarrhea, fever, and abdominal pain.
Rare diagnoses
- Intussusception: A condition where a part of the intestine slides into an adjacent part, which can cause bowel obstruction and bleeding. It's more common in children but can occur in adults.
- Meckel's Diverticulum: A congenital anomaly of the small intestine that can cause bleeding due to the presence of ectopic gastric mucosa.
- Solitary Rectal Ulcer Syndrome: A condition characterized by ulcers in the rectum, often associated with chronic constipation and straining during bowel movements, which can lead to rectal bleeding.