Diverticular disease involves the formation of small pouches, known as diverticula, that protrude outward through weak spots in the wall of the large intestine, or colon. This condition, called diverticulosis, is common, especially with increasing age, affecting an estimated 5% of people by age 40 and at least 50% by age 80. Diverticular bleeding occurs when blood vessels within these pouches rupture, leading to visible blood in the stool. While often self-limiting, it can sometimes be a serious medical event.
How Diverticular Bleeding Occurs
Diverticula are thought to form when high pressure inside the colon pushes against weak areas in the colon wall. These weak spots are typically where small blood vessels penetrate the muscle layer. When these blood vessels within the diverticular wall become injured, bleeding occurs.
This bleeding typically presents as a sudden, often painless, passage of a large amount of bright red or dark maroon blood from the rectum, sometimes with blood clots. Unlike other gastrointestinal issues, diverticular bleeding is not accompanied by abdominal pain. Although the volume of blood can be alarming, the bleeding often stops on its own.
When Bleeding Becomes a Concern
About 10% to 20% of individuals may experience significant blood loss, or hemorrhage. Significant blood loss can lead to serious symptoms requiring immediate medical attention. Signs of severe bleeding include dizziness, weakness, or fainting, suggesting a drop in blood pressure.
A rapid heart rate is another indicator of substantial blood loss, as the body tries to compensate for reduced blood volume. In some cases, individuals may show signs of shock, such as confusion, pale skin, or cold, clammy skin. Ongoing, heavy bleeding can lead to anemia, and may necessitate blood transfusions.
Medical Intervention and Management
When diverticular bleeding is suspected, diagnosis typically begins with a medical history and physical examination to rule out other causes of rectal bleeding. A colonoscopy is often the recommended initial diagnostic test, performed within 12 to 48 hours after presentation, following a rapid bowel preparation. It allows direct visualization of the colon to identify and treat the bleeding site.
During a colonoscopy, if the bleeding source is identified, endoscopic techniques like injecting epinephrine, applying clips, or using electrocautery can stop the bleeding. If the bleeding is severe or ongoing and a colonoscopy is not conclusive, other imaging tests such as angiography may be used. Angiography involves injecting a dye to locate the bleeding, allowing for targeted treatment like embolization, which blocks the bleeding vessel. In rare instances where other interventions fail or if there is persistent instability, surgical removal of the affected colon may be necessary.
Reducing Your Risk
Certain lifestyle adjustments can help reduce the risk of diverticular disease and prevent bleeding episodes. A diet rich in fiber is recommended, aiming for 20 to 35 grams daily. Foods high in fiber include whole grains, fruits like berries, and vegetables such as broccoli and spinach.
Adequate hydration is also important, as drinking plenty of fluids helps fiber move through the digestive system smoothly, preventing constipation. Regular physical activity contributes to healthy bowel movements and may further support colon health. Avoiding regular use of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) can also lower the risk of diverticular bleeding.