What Causes Rectal Bleeding?

Hematochezia (passage of bright red blood per rectum) may result from the following conditions:

1. Hemorrhoidal bleeding—this is the most common cause, typically presenting as blood mixed with stool or bleeding after defecation, usually in the form of fresh, bright red blood.

2. Ulcerative colitis—typically characterized by bloody, purulent stools accompanied by abdominal pain; the disease course is often recurrent and chronic, and long-standing cases may be associated with weight loss.

3. Gastrointestinal malignancies—bleeding caused by intestinal tumors is frequently accompanied by changes in bowel habits (e.g., frequency, urgency, or tenesmus) or alterations in stool caliber (e.g., narrowing).

4. Hematologic disorders—such as thrombocytopenia or coagulopathies—may also lead to gastrointestinal bleeding and subsequent hematochezia.

The above descriptions are based solely on clinical symptoms; definitive diagnosis requires further investigations, such as colonoscopy.