Stercoral colitis (SC) is a serious, uncommon form of colon inflammation and ulceration caused by severe, chronic constipation. This condition develops when a large, hardened mass of stool becomes lodged within the colon. This impacted fecal matter causes mechanical pressure and injury to the colon wall. Stercoral colitis demands prompt medical intervention because it can quickly progress to life-threatening complications, including bowel perforation.
How Fecal Impaction Leads to Colitis
Stercoral colitis begins with severe, prolonged fecal impaction, often in the rectosigmoid junction, the narrowest part of the large intestine. The stagnant fecal material dehydrates and hardens into a dense mass known as a fecaloma. This hard mass exerts intense pressure against the inner lining of the colon wall.
This sustained pressure compresses small blood vessels within the colon wall, reducing blood flow to the tissue. This lack of adequate blood supply, known as localized ischemia, prevents cells from receiving oxygen and nutrients. The resulting tissue damage is called pressure necrosis, leading to deep ulcers in the colon lining. These ulcers are most common on the antimesenteric border of the colon, the side farthest from the main blood vessels, making it vulnerable to poor circulation.
Stercoral colitis most frequently affects the elderly, especially those with dementia or limited mobility, and individuals who are bedridden. Chronic constipation is the foundation for this condition, often exacerbated by medications, such as opioids, that decrease intestinal movement. Patients who cannot sense or communicate their symptoms effectively are at high risk.
Identifying the Clinical Signs
Patients frequently present with a history of worsening constipation followed by severe abdominal discomfort. This pain is often localized to the left lower quadrant of the abdomen, corresponding to the rectosigmoid area where impaction is common. The abdomen may appear swollen and feel tender when pressed.
A characteristic symptom is paradoxical diarrhea, where liquid stool leaks around the blockage. This can lead to the mistaken assumption that the patient is not constipated. Systemic signs of infection or inflammation, such as fever or a rapid heart rate, suggest progression to a severe stage. In the most severe cases, patients may show signs of peritonitis or septic shock, indicating colon perforation.
Confirming the Diagnosis
Diagnosis relies heavily on medical imaging, as clinical signs alone can be non-specific or difficult to assess. A computed tomography (CT) scan of the abdomen and pelvis is the most informative tool. The CT scan clearly visualizes the impacted, dense fecal mass (fecaloma) and often shows a widening of the colon lumen.
The imaging also reveals signs of inflammation related to the pressure injury. This includes thickening of the colon wall (greater than three millimeters) and inflammation in the surrounding fatty tissue. The CT scan can identify life-threatening complications, such as free air in the abdominal cavity, which indicates colon perforation. Laboratory blood tests check for signs of systemic stress, such as leukocytosis, which is an elevated white blood cell count indicating infection.
Immediate Treatment and Recovery
Immediate management focuses on removing the impacted stool and supporting the patient’s health. For patients without signs of perforation or severe systemic infection, conservative therapy is attempted first. This involves an aggressive bowel regimen, including manual disimpaction of the rectal mass, along with enemas and laxatives to soften and mobilize the remaining stool. Intravenous fluids correct dehydration, and broad-spectrum antibiotics are started to address potential infection.
Surgical intervention is necessary for complicated cases, particularly if the colon has perforated or if conservative methods fail. A perforated colon requires urgent surgery to resect (remove) the diseased section of the bowel. This procedure often involves a colostomy, where the healthy end of the colon is brought through the abdominal wall to divert waste.
Long-term recovery and prevention center on managing the chronic constipation underlying the condition. This involves establishing a consistent bowel regimen, including increasing dietary fiber and fluid intake. Patients are monitored by specialists, such as gastroenterologists, to address underlying causes of reduced bowel motility and prevent recurrence.