Toxic megacolon

A severe complication of colonic diseases

Toxic megacolon is a severe complication of colonic diseases, characterized by an extreme dilation of the colon. It is most commonly associated with inflammatory bowel diseases such as ulcerative colitis and Crohn's disease, but can also occur due to infections like Clostridioides difficile colitis.

Signs and symptoms

Patients with toxic megacolon typically present with abdominal pain, distension, fever, tachycardia, and signs of systemic toxicity. The condition can lead to perforation of the colon, sepsis, and can be life-threatening if not treated promptly.

Causes

Toxic megacolon is often a complication of severe inflammation of the colon. The most common causes include:

• Ulcerative colitis
• Crohn's disease
• Infectious colitis, particularly due to Clostridioides difficile
• Ischemic colitis

Pathophysiology

The pathophysiology of toxic megacolon involves severe inflammation of the colonic wall, leading to paralysis of the colonic muscles and subsequent dilation. The inflammation can also cause damage to the colonic mucosa, increasing the risk of perforation.

Diagnosis

Diagnosis is typically made based on clinical presentation and imaging studies. Abdominal X-ray or CT scan can show the dilated colon. Laboratory tests may reveal leukocytosis and electrolyte imbalances.

Treatment

Treatment of toxic megacolon involves addressing the underlying cause, supportive care, and sometimes surgical intervention. Initial management includes bowel rest, intravenous fluids, and broad-spectrum antibiotics. In cases where medical management fails, surgical options such as colectomy may be necessary.

Prognosis

The prognosis of toxic megacolon depends on the underlying cause and the timeliness of treatment. Early recognition and treatment are crucial to prevent complications such as perforation and sepsis.

Related pages

• Ulcerative colitis
• Crohn's disease
• Clostridioides difficile

Images

• Pseudomembranes in the colon, often associated with Clostridioides difficile infection.

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  Toxic megacolon in a patient with ulcerative colitis.

• Surgical specimen showing toxic megacolon.

• Colonic pseudomembranes at low magnification

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  Toxic megacolon in ulcerative colitis

• Toxic megacolon