Eosinophilic colitis (EC) is a rare inflammatory condition affecting the large intestine. It is characterized by an unusual accumulation of eosinophils, a type of white blood cell, within the colon’s tissues. EC is part of eosinophilic gastrointestinal disorders (EGIDs), which involve excessive eosinophil presence in various parts of the digestive tract. This condition can impact individuals across all age groups.
Understanding Eosinophilic Colitis
Eosinophils are immune cells normally found in the gastrointestinal tract, where they contribute to immune responses against parasites and maintain the mucosal barrier. In eosinophilic colitis, these cells accumulate in abnormally high numbers in the large intestine. This excessive presence leads to inflammation, causing redness, swelling, and damage to the intestinal lining.
The exact mechanisms causing this accumulation are not fully understood, but allergic reactions or immune system dysregulation often play a role. Eosinophils release toxic proteins (e.g., major basic protein, eosinophil cationic protein) and other chemicals that contribute to tissue damage and inflammation. While a chronic condition, symptom severity can fluctuate over time.
Recognizing the Signs
Symptoms of eosinophilic colitis can differ widely and often resemble other gastrointestinal conditions, making diagnosis a challenge. Abdominal pain is a common symptom, ranging from a dull ache to sharp, colicky sensations. Diarrhea is also frequently reported and may contain visible blood, appearing bright red to dark black.
Other manifestations include nausea and vomiting, which can contribute to difficulty feeding or gaining weight, particularly in infants. Weight loss and poor growth are also observed, stemming from malabsorption or reduced food intake. Additionally, individuals may experience fatigue and develop anemia due to chronic blood loss.
How Eosinophilic Colitis is Diagnosed
Diagnosis of eosinophilic colitis typically begins with a thorough review of the patient’s medical history and a physical examination. Blood tests may check for elevated eosinophil counts, though a normal count does not rule out the condition. These tests can also identify signs of inflammation or anemia.
A colonoscopy is a standard diagnostic procedure. A flexible tube with a camera is inserted to visualize the large intestine. During this procedure, small tissue samples, called biopsies, are taken from various sections of the colon. These biopsies are then examined under a microscope by a pathologist to identify and count the number of eosinophils present.
While some eosinophils are normally present, an abnormally high concentration, such as more than 20 eosinophils per high-power field in some areas, supports an EC diagnosis. Other conditions causing elevated eosinophil levels in the colon, such as parasitic infections, inflammatory bowel disease, or drug reactions, must be ruled out.
Managing Eosinophilic Colitis
Management strategies for eosinophilic colitis are often individualized due to the condition’s varying nature and lack of standardized treatment guidelines. Dietary modifications are a common approach, especially in infants where the condition is often linked to cow’s milk protein or soy. Elimination diets, which involve removing specific foods to identify and avoid triggers, can reduce symptoms and inflammation.
Medications are frequently used to manage symptoms and reduce inflammation. Corticosteroids, such as prednisone, are often prescribed to suppress the immune response and decrease eosinophil activity. These can be administered systemically or topically via enemas or suppositories for more localized effects.
For more severe or persistent cases, other immunomodulators may be considered to regulate the immune system and reduce inflammation long-term. Supportive care, including iron supplements for anemia, is also provided to address specific symptoms and improve overall well-being. Regular monitoring through follow-up endoscopies and biopsies may be necessary to assess treatment effectiveness and make adjustments.