Diverticulitis, the inflammation or infection of small pouches (diverticula) along the colon walls, can cause anemia. Anemia is defined by a lack of healthy red blood cells or low hemoglobin levels, and it is a frequent complication of diverticular disease. This inflammation often leads to chronic blood loss within the gastrointestinal tract, resulting in the body’s inability to produce enough red blood cells. The physiological link makes anemia an important symptom requiring medical investigation.
How Diverticulitis Causes Blood Loss and Anemia
The primary mechanism linking diverticulitis to anemia is chronic gastrointestinal bleeding. Diverticula form where small blood vessels penetrate the muscular layer of the colon wall. When these pouches become inflamed during an episode of diverticulitis, the nearby blood vessels are subject to irritation and erosion.
This erosion often results in a slow, persistent leak of blood into the colon. This type of bleeding can go unnoticed because it is not obvious in the stool. Even a small, continuous loss of blood over time depletes the body’s iron stores. Since iron is an essential component of hemoglobin, this chronic loss leads specifically to iron-deficiency anemia.
In less common, acute cases, a blood vessel near a diverticulum can rupture completely, causing a sudden and significant hemorrhage. This rapid blood loss leads to an immediate drop in hemoglobin levels and can present as bright red or maroon blood in the stool. The loss of blood volume and iron content, whether chronic or severe, directly causes the development of anemia.
A secondary factor contributing to anemia is the inflammation itself. Chronic inflammation associated with diverticulitis can interfere with the absorption of nutrients, including iron and B vitamins. Furthermore, the body’s inflammatory response can inhibit the efficient use of stored iron, a condition sometimes termed the anemia of chronic disease. However, blood loss from damaged vessels remains the most frequent cause of iron-deficiency anemia.
Identifying the Source Through Medical Testing
Confirming diverticulitis as the cause of anemia requires specific medical tests to assess the type of anemia and rule out other potential causes of gastrointestinal bleeding. The initial step involves a Complete Blood Count (CBC) test, which measures red blood cells and hemoglobin levels. In cases of chronic iron deficiency, the CBC typically reveals microcytic, hypochromic anemia, meaning the red blood cells are smaller and paler than normal due to low iron content.
Following the confirmation of anemia, further tests pinpoint the source of blood loss. A fecal occult blood test checks for microscopic amounts of blood in the stool, confirming a slow internal bleed. Blood iron panel tests, including serum ferritin, measure the body’s iron reserves; a low ferritin level strongly indicates iron-deficiency anemia.
The definitive diagnostic tool for internal bleeding in the colon is a colonoscopy. This procedure allows a physician to visually inspect the entire large intestine and identify the diverticula. It also helps rule out other serious causes of lower gastrointestinal hemorrhage, such as polyps or colorectal cancer. The combination of these blood and imaging tests links the anemia directly to the diverticular disease.
Comprehensive Treatment for Anemia Linked to Diverticulitis
Effective management of anemia caused by diverticulitis requires a dual approach: treating the resulting iron deficiency and addressing the underlying inflammation and bleeding. Treatment often begins with oral iron supplements, such as ferrous sulfate, fumarate, or gluconate, to replenish the body’s depleted stores. This oral supplementation typically continues for about three months after hemoglobin levels normalize to ensure iron reserves are fully restored.
If anemia is severe, or if the patient cannot tolerate or absorb oral iron due to gastrointestinal side effects, intravenous (IV) iron therapy is necessary. IV iron is a highly effective method for rapidly increasing iron levels and is often preferred during periods of active diverticulitis inflammation. For patients with life-threatening blood loss or very low hemoglobin levels, a blood transfusion may be required to quickly stabilize the condition.
Simultaneously, the underlying diverticulitis must be managed to stop the ongoing blood loss. Treatment includes dietary changes, such as increasing fiber intake to promote healthy bowel function and reduce pressure on the colon walls. During acute flares, antibiotics are prescribed to clear any infection. In severe or recurring instances of bleeding, surgical resection to remove the affected segment of the colon may be considered.