Chemotherapy, a common treatment for various cancers, targets rapidly dividing cells. While highly effective, this mechanism can inadvertently affect healthy cells in the body that also divide quickly. One such area is the gastrointestinal tract, and colitis, inflammation of the colon, is a known side effect for some patients.
How Chemotherapy Affects the Gut
Chemotherapy drugs are designed to eliminate rapidly proliferating cancer cells, but they often lack the ability to distinguish these from other fast-growing cells. The cells lining the gastrointestinal tract, particularly those in the colon, constantly divide and regenerate. When chemotherapy agents reach these healthy cells, they can damage them, leading to inflammation and disruption of the gut lining.
This damage can also alter the gut microbiome, reducing beneficial bacteria and allowing harmful bacteria to overgrow. This dysregulation contributes to the inflammatory process within the colon. Different chemotherapy agents, such as fluoropyrimidines (e.g., 5-FU, capecitabine) and irinotecan, are particularly recognized for their propensity to induce gastrointestinal toxicity, including colitis.
Identifying Symptoms of Colitis
Patients experiencing chemotherapy-induced colitis often report a range of symptoms, with diarrhea being one of the most prominent. This diarrhea can vary in severity, from increased frequency of loose stools to severe, watery bowel movements that may contain blood or mucus. Abdominal pain and cramping are also common, often described as a generalized discomfort or sharp pains in the lower abdomen. These symptoms arise from the inflammation and irritation of the colon wall.
Other symptoms can include nausea and vomiting, which may contribute to fluid loss. A low-grade fever might also be present, indicating an inflammatory response. Due to fluid loss from diarrhea and vomiting, dehydration can become a serious concern, leading to symptoms like excessive thirst, dry mouth, and reduced urination. Promptly report any of these symptoms to the healthcare team for early intervention and management.
Diagnosis and Medical Management
Diagnosing chemotherapy-induced colitis typically begins with a thorough physical examination and a detailed review of the patient’s symptoms and recent chemotherapy regimen. Healthcare professionals will often order stool tests to rule out infectious causes of diarrhea, as certain bacterial or viral infections can mimic colitis symptoms and require different treatments. Blood tests may also be performed to assess hydration status and check for signs of inflammation.
In more severe or persistent cases, imaging studies like a computed tomography (CT) scan of the abdomen and pelvis may be used to visualize the colon and assess the extent of inflammation. Endoscopic procedures, such as a colonoscopy, might be considered to directly examine the colon lining and obtain tissue biopsies for microscopic analysis, confirming the presence and severity of inflammation. Medical management focuses on supportive care, including intravenous fluids to correct dehydration and electrolyte imbalances. Anti-diarrheal medications, such as loperamide, are often prescribed to reduce stool frequency, and pain management strategies are implemented to alleviate abdominal discomfort. In severe instances, or when symptoms do not improve, the chemotherapy dosage may be temporarily held or adjusted to allow the colon to heal.
Patient Support and Self-Care
Patients experiencing chemotherapy-induced colitis can take several self-care measures to help manage symptoms and promote healing alongside medical treatment. Dietary adjustments are often recommended, such as consuming a bland diet that is low in fiber and avoiding foods that can irritate the gut, like spicy foods, high-fat items, and dairy products. Maintaining adequate hydration is important, which involves regularly sipping on clear broths, water, or electrolyte-rich drinks.
Good perianal hygiene is also important to prevent skin irritation and breakdown due to frequent bowel movements. This can involve gentle cleansing with warm water and using barrier creams. Managing fatigue is also key, and patients should prioritize rest. Open and consistent communication with the healthcare team is essential, allowing them to monitor symptoms, adjust treatments as needed, and provide personalized advice for managing this side effect.