Rates of C. diff recurrence are high. Once you experience an episode of recurrence, the odds of experiencing another one increase significantly.

C. diff is a bacteria that can cause diarrhea and inflammation in your colon. Recurrence of C. diff is common.

Once you’ve had one episode of recurrence, your risk of further episodes increases.

Learn more about C. diff recurrence, why it happens, and how common is it, as well as risk factors, symptoms, and prevention strategies.

C. diff — also called Clostridioides difficile, or C. difficile — is a type of bacteria that causes inflammation of your colon, leading to diarrhea.

It can happen if you take antibiotics that change the bacteria in your colon, allowing the C. diff bacteria to grow.

Recurrent C. diff infection is a C. diff infection that happens again. An episode of C. diff is typically considered recurrent if it happens within 8 weeks of a previous infection.

C. diff has a high recurrence rate.

Roughly 1 in 6 people who have had a C. diff infection will experience another in the 2–8 weeks after their previous episode.

Once the first recurrence has resolved, the risk of another recurrence increases. A 2019 research review suggests that about 40% of people will experience a second recurrence after recovering from their first.

The same review notes that the recurrence rate is 45–65% in people who have had more than two recurrences of C. diff.

Since 2000, the United States, Canada, and other countries have seen a significant increase in both the number of C. diff cases and the severity.

An older research review found that in the years 2003 through 2006, cases of C. diff were more frequent, more harmful, less responsive to treatment, and more likely to return than they had been previously.

These increases may be partially due to the emergence of a particularly severe strain of C. diff known as NAP1/BI/027.

Increasing antibiotic resistance against C. diff likely also plays a role in recurrence rates.

The increased recurrence rate after a previous recurrence is possibly due to problems related to antibiotic resistance. Using an antibiotic to treat a disease that is caused by antibiotics can worsen the problem. This may be because the healthy bacteria in the colon do not have a chance to regrow.

There are a number of potential risk factors that make a recurrence of C. diff more likely.

Advanced age

Older age is one of the most commonly reported risk factors for recurrent C. diff infection.

A 2005 study found that in the years 2003 through 2004, the chance of a recurrence of C. diff was 25% among people 0–17 years old, 27.1% among people 18–64 years old, and 58.4% in those 65 years and older. These numbers represented a significant increase in likelihood over prior years.

It’s not entirely clear why older people may have a higher rate of recurrence than younger people, but a decrease in immune response in older age and an increase in other medical conditions are believed to play a role.

Antibiotic use

Use of antibiotics is one of the most significant modifiable risk factors for recurrent C. diff infection. This means that, unlike age, it’s a risk factor that can be changed.

People are 7–10 times more likely to contract C. diff while taking antibiotics and in the month after antibiotic treatment.

Antibiotics change the microbiome in your intestines and, in doing so, create an environment in which C. diff can grow. When antibiotics change your gut microbiome, the composition of bile acids in your colon also changes, which can promote the growth of C. diff bacteria.

Studies have found that previous use of antibiotics increases the risk of recurrent C. diff infection.

Hypervirulent strains

People who have contracted the C. diff strain known as NAP1/BI/027 have experienced increased recurrence rates.

This specific strain of C. diff produces more toxins than other strains. It also produces a type of toxins that helps the C. diff bacteria grow and remain in your gut.

Additionally, this strain is very resistant to a class of antibiotics called fluoroquinolones.

In a 2012 clinical trial involving 719 people with C. diff, those who had the NAP1/BI/027 strain had a 27.4% rate of recurrence. In comparison, the recurrence rate in those who had other strains was 16.6%.

Gastric acid suppression

Medications to suppress gastric acid are commonly used to prevent ulcers and other health conditions related to acid. But the loss of acidity in your gut can increase your risk of contracting C. diff.

According to a 2017 research review, recurrent C. diff is more common in people who have used gastric acid suppressants than in those who have not.

Other risk factors

There have been numerous risk factors reported for recurrence of C. diff infection, including:

  • a prolonged hospital stay
  • severe underlying disease
  • decreased kidney function
  • a recent stay in a nursing home
  • a weakened immune system (due to HIV, cancer, or immunosuppressive medications)

If you experience a recurrence of C. diff, you may notice a return of symptoms you previously had.

Symptoms may include:

  • pain in your abdomen
  • tenderness in your stomach
  • diarrhea
  • nausea
  • lack of appetite
  • fever

According to the Centers for Disease Control and Prevention (CDC), the best way to prevent C. diff from coming back is to avoid taking unnecessary antibiotics.

When speaking with healthcare professionals, it’s important to tell them whether you’ve had a C. diff infection before. This will help them make the best decisions for you if they need to prescribe antibiotics. You should also tell your dentist about any prior infections you’ve had.

C. diff bacteria can transfer from one person to another. If someone does not wash their hands thoroughly with soap and water after using the bathroom, the bacteria may transfer when they touch objects or other people.

It’s very important to properly wash your hands with soap and water every time you use the bathroom and before you eat.

In some people, C. diff can return again and again. If that happens, a doctor may recommend other treatments.

For example, they may recommend bezlotuxumab (a drug delivered via IV infusion) alongside a course of antibiotics.

One of the most effective treatments for recurrent C. diff is a fecal microbiota transplant (FMT). During this procedure, stool from a healthy donor is placed in the colon of the person who is experiencing recurrent C. diff. This typically takes place during a colonoscopy.

According to the American College of Gastroenterology, studies have found FMT to be effective in 90% of people who undergo the procedure.

New and less intrusive forms of FMT are now available. There is an enema called Rebyota, which can be administered in a doctor’s office. There are also fecal microbiota capsules, called Vowst, that you can take by mouth. Both are FDA approved. These methods have made fecal transplant much more accessible.

Recurrence rates of C. diff are high. Once you’ve had a recurrence, your odds of experiencing another one increase.

Risk factors such as older age, antibiotic use, gastric acid suppression, and a weakened immune system may increase the likelihood of C. diff recurrence.

By avoiding unnecessary use of antibiotics and always practicing good hand hygiene, you can reduce the chances that C. diff will come back.