Lower GI Bleeding – Healthooz

What is Lower GI Bleeding?

Lower gastrointestinal (GI) bleeding refers to any form of bleeding originating from the lower part of the digestive tract, specifically from the small intestine (below the ligament of Treitz), the colon, rectum, or anus. This condition can range from mild to life-threatening, depending on the cause and the amount of blood loss.

Blood loss from the lower GI tract can present as rectal bleeding, blood in the stool, or dark, tarry stools (melena), depending on the location of the bleeding. It is important to identify the source and cause of the bleeding to determine the most effective treatment.

Causes of Lower GI Bleeding?

Lower GI bleeding can be caused by a variety of conditions, some of which are relatively minor, while others may be more serious. Common causes include:

1. Hemorrhoids?

Hemorrhoids are swollen blood vessels in the rectum or anus and are one of the most common causes of rectal bleeding. The bleeding is usually bright red and occurs during or after a bowel movement.

2. Anal Fissures?

An anal fissure is a small tear or crack in the skin around the anus. It often causes pain and bleeding during or after bowel movements, with bright red blood appearing on the stool or toilet paper.

3. Diverticulosis and Diverticulitis?

Diverticulosis is a condition in which small pouches (diverticula) form in the walls of the colon. These pouches can sometimes bleed, leading to painless rectal bleeding.
Diverticulitis, an inflammation or infection of the diverticula, can also cause bleeding, but it is typically accompanied by abdominal pain and fever.

4. Colorectal Cancer?

Colorectal cancer is a common and potentially serious cause of lower GI bleeding. The bleeding may be subtle and occur over time, resulting in chronic anemia or fatigue. In more advanced stages, visible blood may be found in the stool.

5. Inflammatory Bowel Disease (IBD)?

Conditions such as Crohn’s disease and ulcerative colitis (two types of inflammatory bowel disease) can cause chronic inflammation in the intestines, leading to ulcers, lesions, and bleeding. The blood in the stool may be mixed with mucus and may appear red or maroon.

6. Angiodysplasia?

Angiodysplasia refers to abnormal blood vessels in the colon that are prone to bleeding. It is most commonly found in the elderly and may cause intermittent bleeding.

7. Ischemic Colitis?

Ischemic colitis occurs when the blood supply to the colon is reduced or interrupted, often due to narrowed blood vessels. This condition can cause pain, bleeding, and diarrhea. It is more common in older adults.

8. Gastrointestinal Infections?

Infections caused by bacteria, viruses, or parasites (such as Clostridium difficile, Salmonella, or Shigella) can result in bloody diarrhea, which may lead to lower GI bleeding.

9. Polyps?

Colorectal polyps, which are growths in the lining of the colon or rectum, can bleed, especially if they are large. Although many polyps are benign, some can become cancerous over time.

10. Radiation Proctitis?

Radiation proctitis occurs as a result of radiation therapy used to treat pelvic cancers (e.g., prostate, cervical, or rectal cancer). This treatment can cause inflammation and bleeding in the rectum or colon.

11. Arteriovenous Malformations (AVMs)?

Arteriovenous malformations are abnormal connections between arteries and veins that can form in the GI tract. These malformations can rupture and bleed, often causing intermittent or chronic lower GI bleeding.

Symptoms of Lower GI Bleeding?

The primary symptom of lower GI bleeding is the presence of blood in the stool. However, the appearance of the blood can vary depending on the cause and the location of the bleeding:

Bright red blood in the stool or on toilet paper typically indicates that the bleeding is coming from the rectum or lower colon (e.g., hemorrhoids or anal fissures).
Maroon-colored stools or blood mixed with stool may suggest that the bleeding is originating from the upper colon or small intestine (e.g., diverticulosis or colitis).
Black, tarry stools (melena) often indicate that the bleeding is coming from the upper GI tract, but if bleeding from the lower GI tract is slow and gradual, it can also cause this appearance.

Other symptoms that may accompany lower GI bleeding include:

Abdominal pain or cramping
Fatigue or weakness (due to anemia)
Dizziness or fainting (in severe cases of blood loss)
Changes in bowel habits, such as diarrhea or constipation

In severe cases, if the bleeding is rapid or excessive, shock (a medical emergency) can occur, presenting with:

Rapid pulse
Low blood pressure
Pale skin
Confusion or loss of consciousness

Diagnosis of Lower GI Bleeding?

A thorough evaluation is needed to determine the cause of lower GI bleeding. This may involve several tests and procedures, including:

1. Physical Examination

A healthcare provider will conduct a physical exam, including a digital rectal exam, to check for visible sources of bleeding (such as hemorrhoids or anal fissures).

2. Laboratory Tests

Blood tests may be done to assess hemoglobin levels (to check for anemia) and other markers of blood loss.
Stool tests may be performed to check for signs of infection, blood, or parasites.

3. Endoscopy

Colonoscopy is the most common procedure to examine the colon and rectum directly. A camera is inserted through the anus to visualize the source of the bleeding.
Flexible sigmoidoscopy is a similar procedure, but it only examines the lower part of the colon.
Upper GI endoscopy may be recommended if the source of bleeding is suspected to be in the upper GI tract.

4. Imaging Studies

In some cases, imaging studies such as CT scans or angiography may be used to identify the location of the bleeding, especially when the source is not immediately apparent.

Treatment of Lower GI Bleeding?

The treatment of lower GI bleeding depends on the cause, severity, and location of the bleeding. Common treatment options include:

1. Conservative Management?

In some cases, particularly with mild bleeding, treatment may involve:

Dietary modifications to reduce bowel irritation
Medications (e.g., anti-inflammatory drugs or antibiotics for infections)
Hemorrhoid treatments (e.g., stool softeners, topical medications)

2. Endoscopic Treatment?

Endoscopic procedures (such as banding, sclerotherapy, or laser therapy) may be used to stop bleeding from certain sources, such as diverticular bleeding or vascular malformations.

3. Surgical Intervention?

In cases of severe or ongoing bleeding, surgery may be necessary. This could involve:

Resection of the bleeding portion of the colon (in cases of cancer, diverticulitis, or large polyps)
Repairing blood vessel malformations
Removal of tumors or affected areas in cases of cancer

4. Blood Transfusion?

For patients who have lost a significant amount of blood, blood transfusions may be required to restore hemoglobin levels and prevent shock.

5. Medications?

Hemostatic agents may be used in certain situations to help control bleeding.
IV fluids and electrolyte replacement may be used to maintain hydration and balance during episodes of significant bleeding.

Prevention of Lower GI Bleeding?

While not all cases of lower GI bleeding can be prevented, the following steps can help reduce the risk:

Maintain a high-fiber diet to prevent constipation and strain on the rectum and colon.
Regular screenings for colon cancer and polyps (especially after the age of 50 or for those with a family history).
Avoid excessive alcohol consumption and smoking, both of which can increase the risk of GI problems, including ulcers and cancer.
Manage chronic conditions, such as inflammatory bowel disease, with the help of a healthcare provider to reduce the risk of flare-ups and complications.

When to See a Doctor?

If you notice blood in your stool or experience symptoms like abdominal pain, fatigue, or dizziness, it’s important to seek medical attention immediately. In cases of severe bleeding, such as large amounts of blood in the stool or signs of shock, go to the emergency room for urgent evaluation and treatment.