Differential Diagnosis for a 20-year-old Male with Intermittent Bright Red Blood in Stool
Single most likely diagnosis:
- Hemorrhoids: This is the most common cause of bright red blood in the stool, especially in young adults. The intermittent nature of the bleeding and the bright red color are consistent with hemorrhoids, which are swollen veins in the lowest part of the rectum or anus.
Other Likely diagnoses:
- Anal fissure: A small tear in the lining of the anus can cause bright red bleeding, especially during or after bowel movements. The pain associated with an anal fissure can be severe.
- Diverticulosis: Although more common in older adults, diverticulosis (the presence of small, bulging pouches in the digestive tract) can occur in younger individuals and may cause intermittent bleeding.
- Inflammatory bowel disease (IBD): Conditions like ulcerative colitis or Crohn's disease can cause rectal bleeding, among other symptoms. However, they typically present with additional symptoms such as diarrhea, abdominal pain, and weight loss.
Do Not Miss diagnoses:
- Colorectal cancer: Although rare in young adults, colorectal cancer can present with rectal bleeding and must be considered to avoid a delayed diagnosis.
- Infections (e.g., amoebic dysentery): Certain infections can cause rectal bleeding and are important to diagnose promptly to initiate appropriate treatment.
- Angiodysplasia: Vascular malformations in the colon can cause bleeding, which may be intermittent and can be life-threatening if not recognized.
Rare diagnoses:
- Intussusception: A condition where a part of the intestine slides into an adjacent part, which can cause intermittent bleeding, although it's more common in children.
- Meckel's diverticulum: A congenital anomaly of the small intestine that can cause bleeding due to the presence of ectopic gastric mucosa.
- Arteriovenous malformations (AVMs): Abnormal connections between arteries and veins can cause bleeding in the gastrointestinal tract, including the rectum.