What Causes Rectal Bleeding?

Hematochezia—passing blood per rectum—most commonly results from gastrointestinal bleeding, particularly originating in the colon or rectum; however, upper gastrointestinal bleeding may occasionally present this way. Hematochezia refers to the passage of blood through the anus, either mixed with stool or as pure blood. So, what causes hematochezia? Below is an overview.

Causes of Hematochezia

1. Rectal Disorders

Certain rectal conditions can cause hematochezia. For example, rectal polyps often lead to blood-tinged stools during defecation. Patients with rectal cancer may also experience hematochezia; although anal pain is typically absent during bowel movements, they frequently report anal discomfort, which progressively worsens as the disease advances.

2. Colonic Disorders

Colonic diseases—including colitis, ulcerative colitis, and colorectal cancer—can cause hematochezia. In colitis, hematochezia is a common symptom, though patients may also exhibit mucus discharge, abdominal pain, fever, and increased frequency of bowel movements. Colorectal cancer—a malignant tumor—typically presents with dark red or bright red blood mixed in the stool, accompanied by a sensation of rectal heaviness or pressure.

3. Hemorrhoids

Hemorrhoids are a frequent cause of hematochezia. In severe cases, patients may experience bleeding during defecation—ranging from dripping to spurting—and the blood is typically bright red. Additionally, prolapsed tissue may accompany the bleeding.

4. Anal Fissures

Anal fissures can also cause hematochezia. Patients with anal fissures often experience bleeding during bowel movements, along with perianal pain and constipation. Besides bleeding and pain, patients commonly have discharge from the anal region, necessitating prompt medical evaluation and treatment.

The above outlines the primary causes of hematochezia, including hemorrhoids and anal fissures, as well as colonic and rectal disorders. If you experience hematochezia, it is strongly recommended that you seek timely medical evaluation and diagnosis at a healthcare facility. We hope this information is helpful to you.