What is toxic megacolon?
The large intestine is the lowest section of your digestive tract. It includes your appendix, colon, and rectum. The large intestine completes the digestive process by absorbing water and passing waste (stool) to the anus.
Some conditions can cause the large intestine to malfunction. One such condition is toxic megacolon or megarectum. Megacolon is a general term that means the abnormal dilation of the colon. “Toxic megacolon” is a term used to express the seriousness of the condition.
Toxic megacolon is rare. It’s a widening of the large intestine that develops within a few days and can be life threatening. It can be a complication of inflammatory bowel disease (IBD) or certain types of infection.
One of the causes of toxic megacolon is IBD, an umbrella term for conditions such as ulcerative colitis and Crohn’s disease. IBD can cause swelling and irritation in parts of your digestive tract. It can be painful and cause permanent damage to your large and small intestines.
Infections such as Clostridium difficile colitis can cause toxic megacolon.
Toxic megacolon occurs when inflammation or infection causes the colon to expand, dilate, and distend. When this happens, the colon cannot remove gas or feces from the body. If gas and feces build up in the colon, your large intestine may rupture.
Rupture of your colon is life threatening. If your intestines rupture, bacteria in your intestine are released into your abdomen. This can cause infection and death.
There are other types of megacolon, including:
- pseudo-obstruction megacolon
- colonic ileus megacolon
- congenital colonic dilation
Although these conditions can expand and damage the colon, they’re not due to inflammation or infection.
When toxic megacolon occurs, the large intestines rapidly expand. Symptoms of the condition may come on suddenly and include:
- abdominal pain
- bloating of the abdomen (distention)
- abdominal tenderness
- rapid heart rate (tachycardia)
- bloody or profuse diarrhea
- painful bowel movements
Toxic megacolon is a life threatening condition. If these symptoms develop, seek immediate medical attention.
If you develop toxic megacolon symptoms, a doctor can confirm a diagnosis after a physical exam and other tests.
Your doctor will ask you about your health history and whether you have IBD. They will check to see whether you have a tender abdomen. They will also listen for bowel sounds through a stethoscope placed on your abdomen.
If your doctor suspects that you have toxic megacolon, they may order more tests, such as:
- abdominal X-rays
- CT scan of the abdomen
- blood tests such as a complete blood count (CBC) and blood electrolytes
Treatment for toxic megacolon usually involves surgery.
If you develop this condition, you will be admitted to the hospital. You will receive fluids to prevent shock. Shock is a life threatening condition that can happen when an infection in the body causes your blood pressure to decrease rapidly.
Once your blood pressure is stable, you’ll need surgery to correct toxic megacolon. In some cases, toxic megacolon may produce a tear or perforation in the colon. This tear must be repaired to prevent bacteria from the colon from entering the body.
Even if there’s no perforation, the colon’s tissue may be weakened or damaged and need removal. Depending on the extent of the damage, you may need to undergo a colectomy. This procedure involves either a complete or partial removal of the colon.
You’ll take antibiotics during and after the surgery. Antibiotics help prevent a serious infection known as sepsis. Sepsis causes a severe reaction in the body that is often life threatening.
Read more about total proctocolectomy with ileostomy.
Toxic megacolon is a complication of IBD or infections.
If you have IBD or an infection, follow your prescribed treatment and management plan. This may include making lifestyle changes like quitting smoking and staying active, and taking prescription medications.
These steps can help control the symptoms of IBD, prevent infections, and reduce the likelihood of developing toxic megacolon.
If you develop toxic megacolon and promptly seek treatment at a hospital, your long-term outlook is typically good. Seeking emergency medical treatment for this condition will help prevent complications, including:
- perforation (rupture) of the colon
If toxic megacolon complications occur, you need complete removal of the colon. This may require you to put an ileostomy or ileoanal pouch-anal anastomosis (IPAA) in place. These devices will remove feces from your body after your colon is removed.
Toxic megacolon is a rare but serious complication of IBD or infection. Left untreated, it can lead to rupture of your colon, which can cause serious infection and become life threatening.
Following your doctor-prescribed treatment and management plan can help prevent toxic megacolon. If you do develop toxic megacolon, prompt diagnosis and treatment are key.