Toxic megacolon

  • Definition
    • Toxic megacolon occurs when swelling and inflammation spread into the deeper layers of your colon. As a result, the colon stops working and widens. In severe cases, the colon may rupture.

  • Alternative Names
    • Toxic dilation of the colon; Megarectum; Inflammatory bowel disease - toxic megacolon; Crohn disease - toxic megacolon; Ulcerative colitis - toxic megacolon

  • Causes
    • The term "toxic" means that this problem is very dangerous. Toxic megacolon may occur in people with an inflamed colon due to:

      Other forms of megacolon include pseudo-obstruction, acute colonic ileus, or congenital colonic dilation. These conditions do not involve an infected or inflamed colon.

  • Symptoms
    • The rapid widening of the colon may cause the following symptoms to occur over a short period of time:

      If the colon ruptures, symptoms may include

      • Rapid heart rate
      • Shock, when a bodywide infection leads to dangerously low blood pressure
  • Exams and Tests
  • Treatment
    • Treatment of the disorder that led to toxic megacolon may be started, including:

      • Steroids and other medicines that suppress the immune system
      • Antibiotics

      If you have septic shock, you will be admitted to the intensive care unit of the hospital. Treatment may include:

      • Breathing machine (mechanical ventilation)
      • Dialysis for kidney failure
      • Drugs to treat low blood pressure, infection, or poor blood clotting
      • Fluids given directly into a vein (intravenously)
      • Oxygen

      If rapid widening is allowed to continue, an opening or rupture can form in the colon. Therefore, most cases of toxic megacolon will need surgery to remove a part of or the entire colon.

      You may receive antibiotics to prevent sepsis (a severe infection).

  • Outlook (Prognosis)
    • If the condition does not improve, it can be life threatening. In this case, a colectomy is usually needed.

  • Possible Complications
    • Complications may include:

      • Perforation of the colon
      • Sepsis
      • Shock
  • When to Contact a Medical Professional
    • Go to the emergency room or call the local emergency number (such as 911) if you develop severe abdominal pain, especially if you also have:

      • Bloody diarrhea
      • Fever
      • Frequent diarrhea
      • Rapid heart rate
      • Tenderness when the abdomen is pressed
  • Prevention
    • Treating diseases that cause toxic megacolon, such as ulcerative colitis or Crohn disease, can prevent this condition.

  • References
    • Lichtenstein GR. Inflammatory bowel disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 141.

      Marrero F. Severe complications of inflammatory bowel disease. Med Clin North Am. 2008;92:671-686. PMID: 18387381

      Peterson MA. Disorders of the large intestine. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 95.