Table of Contents
Toxic Megacolon Definition
Toxic Megacolon is a serious condition in which a loss of MUSCLE tone in the lower COLON (typically the sigmoid colon) causes the preceding segment of colon to greatly enlarge (dilate). Air accumulates in the dilated bowel, increasing the pressure. Without prompt treatment intestinal perforation (rupture) is highly likely, with consequential PERITONITIS.
Toxic megacolon is a potentially lifethreatening condition that requires emergency medical treatment and often surgery.
Toxic megacolon is usually a complication of inflammatory conditions affecting the gastrointestinal tract, such as INFLAMMATORY BOWEL DISEASE (IBD) or INFECTION (COLITIS). The congenital disorder HIRSCHSPRUNG’S DISEASE, in which the lower colon lacks nerves, can cause toxic megacolon in a newborn infant.
Symptoms of Toxic Megacolon and Diagnostic Path
A person who has toxic megacolon is very sick. Usually there is FEVER along with ABDOMINAL DISTENTION, rigidity, and PAIN. REBOUND TENDERNESS and absence of BOWEL SOUNDS are common findings. The person may be in SEPTICEMIA (septic SHOCK), indicating PERITONITIS. The doctor often can make the diagnosis with an abdominal X-RAY that shows the dilated colon.
Toxic Megacolon Treatment Options and Outlook
ANTIBIOTIC MEDICATIONS, CORTICOSTEROID MEDICATIONS, depending on the cause of the condition, and intravenous fluids to counter DEHYDRATION may help stabilize the colon, in combination with positional changes to attempt to move air (intestinal gas) out of the bowel to help relieve the distention. Surgery to remove the dilated segment of bowel (colectomy) is often the only treatment to prevent or treat bowel perforation. The surgeon then connects the two healthy ends of bowel together to restore normal bowel function. With prompt and appropriate treatment, many people make a full recovery from toxic megacolon. However, it does present a serious challenge to the body’s HEALING abilities. As well, any underlying conditions that precipitated the bowel dilation may continue to cause symptoms.
Risk Factors and Preventive Measures
The primary risk factor for toxic megacolon is any condition that causes INFLAMMATION of the colon. Taking medications to slow gastric motility (such as to treat DIARRHEA) may contribute to the circumstances resulting in toxic megacolon. Anyone who has colitis, GASTROENTERITIS, DIVERTICULAR DISEASE, CELIAC DISEASE, IBD, or other inflammatory condition affecting the gastrointestinal tract who experiences symptoms that could suggest toxic megacolon should see a doctor without delay.