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Clostridioides (formerly Clostridium) difficile-Induced Colitis (C. diff)


The Manual's Editorial Staff

Reviewed/Revised Jul 2023
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What is C. diff?

Your colon is your large intestine. Colitis is inflammation of the colon. Clostridioides difficile is bacteria that causes colitis. With colitis, you'll have diarrhea (loose, watery poop) and other symptoms. Clostridioides difficile and the illness it causes are often called C. difficile or C. diff.

  • Symptoms range from mild diarrhea to frequent bloody diarrhea plus belly pain and fever

  • To tell if you have C. diff, doctors test your stool (poop) and sometimes use a viewing tube to look at your large intestine

  • You're most likely to get C. diff after you've been taking antibiotics for a different illness

  • People with mild C. diff sometimes get better when they stop taking the antibiotic that caused the problem

  • If diarrhea doesn't go away or is more severe, you need to take another antibiotic to kill the C. diff bacteria

What causes C. diff?

Many types of germs (microorganisms) normally live inside your large intestine. C. diff is one of those germs. Usually these germs are harmless. However, sometimes, one of those germs grows out of control and makes you sick. When C. diff grows out of control, it makes a substance (toxin) that hurts the lining of your intestine and causes diarrhea.

Taking antibiotics for a different infection is the most common cause of C. diff growing and causing an infection. The antibiotics upset the balance of different bacteria in your intestine and allow C. diff to take over.

The risk of C. diff. increases as you get older. The risk is also high among infants and young children. Other risk factors are:

  • Having a severe underlying disease

  • Having a long stay in the hospital

  • Living in a nursing home

  • Having surgery on your stomach or intestines

Sometimes, doctors don't know why a person gets C. diff.

What are the symptoms of C. diff?

Symptoms often start 5 to 10 days after starting antibiotics for another infection. But you may not have symptoms until up to 2 months after you stop taking the antibiotics.

Symptoms range from mild diarrhea to:

  • Bloody diarrhea

  • Belly pain

  • Fever

  • Rarely, feeling sick to your stomach or throwing up

The most severe cases may cause serious complications, such as:

How can doctors tell if I have C. diff?

Doctors suspect C. diff if you have diarrhea within:

  • 2 months of using an antibiotic

  • 72 hours of being admitted to a hospital

Doctors then look for:

  • C. diff and its toxin in a stool sample

  • Inflammation (colitis) and other changes in your large intestine by looking inside it with a viewing tube

How do doctors treat C. diff?

Doctors treat C. diff by:

  • Stopping the antibiotic that caused the problem

  • Giving an antibiotic by mouth that works against C. diff

You shouldn't take medicines that slow down or stop diarrhea. That keeps the C. diff toxins in your intestine and can make you sicker.

One in 5 people have symptoms return, sometimes over and over again. To help prevent symptoms from returning, you may get:

  • Long-term antibiotics

  • Probiotics (pills that can help restore the balance of bacteria in your intestine)

  • A stool transplant (someone’s healthy stool is put into your intestine to balance the bacteria)

If symptoms are very bad, you may need to stay in the hospital where doctors will give you:

Rarely, doctors do surgery to remove a very badly infected intestine.

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