C. diff, short for Clostridioides difficile (formerly called Clostridum difficile), is a type of bacteria that can cause an infection in your colon, the longest part of your large intestine. In most cases, a C. diff infection causes mild symptoms, like diarrhea, but in rare instances it can lead to serious damage to your colon.
Most C. diff infections happen after you take antibiotics. They are more common in older adults — especially ones who are in the hospital or a long-term care facility. But younger people can get C. diff infections, too.
What Is C. diff?
There are trillions of bacteria that live in your colon. Most of them are harmless and many are actually helpful, supporting digestion and keeping your immune system strong.
C. diff is one type of bacteria that can live harmlessly in your gut without causing problems. Some research shows that about 5% of healthy adults have C. diff in their stool without any symptoms.
Problems can arise when something disrupts the balance of bacteria in your gut. If this happens, C. diff can multiply and release toxins that damage the lining of your intestines, cause inflammation, and lead to other unpleasant symptoms like diarrhea.
Each year, roughly half a million people in the U.S. get a C. diff infection. It’s now one of the most common infections in hospitals and long-term care facilities.
How Do You Get a C. diff Infection?
C. diff spreads when bacteria from an infected person’s poop gets onto objects or surfaces. These germs are common. They can be found in homes, hospitals, and even soil. You can get infected if you touch a contaminated surface and then touch your mouth.
Outside the body, C. diff forms tiny, inactive spores with a protective coating. This coating lets them survive for months on other surfaces. If you swallow C. diff spores, they can become active inside your intestines. But this doesn’t always mean you’ll get sick. If you’re healthy, the good bacteria in your gut usually keep C. diff under control.
Antibiotics are one of the most common triggers for a C. diff infection. Paul Feuerstadt, MD, associate clinical professor of digestive diseases at Yale School of Medicine, says that while these drugs kill harmful bacteria that make you sick, they also get rid of the good germs that normally help your body fight off infections. This can also happen if you have a weakened immune system. “A healthy, diverse microbiome minimizes your risk of getting C. diff,” he says.
Is C. diff contagious?
C. diff is very contagious. The bacteria form spores that are hard to kill, both inside and outside the body. These spores can survive heat, stomach acid, many antibiotics, and some disinfectants, including hand sanitizer.
If you carry C. diff in your intestines but don’t have an active infection, you can still spread the bacteria to other people.
C. diff Infection Symptoms
The most common symptom of a C. diff infection is watery diarrhea. In mild cases, you may have
diarrhea at least three times a day. If the infection becomes more serious, it can happen more often — up to 15 times per day.
C. diff diarrhea is often soft or mushy rather than completely liquid. It may have a green tint or contain small amounts of blood or pus. Some people notice a strong, unusual smell that may seem sweet.
Other symptoms include:
- Belly pain or cramping
- A swollen or bloated abdomen
- Nausea and vomiting
- Loss of appetite
- Fever
- Fast heart rate
When to see a doctor
Feuerstadt says that if you’ve recently taken antibiotics or have been in the hospital and have had three or more loose bowel movements a day for two to three days, you should speak with your doctor.
C. diff Risk Factors
Anyone can get a C. diff infection, but it’s most common if you’re taking antibiotics. Your chances of getting an infection can be as much as 10 times higher while you’re on antibiotics and in the three months after you finish them.
You also may be more like to get a C. diff infection if you:
- Are over the age of 65. This may be because your immune system is weaker or you’re taking more medications.
- Spend time in the hospital or a long-term care facility, since C. diff spreads more easily in shared spaces like bathrooms.
- Have a weakened immune system. This can be caused by conditions like cancer, HIV, kidney disease, or diabetes. Immunosuppressant drugs can also affect your gut.
- Have inflammatory bowel disease (IBD), such as Crohn’s and ulcerative colitis. These conditions can weaken your intestines over time, making you more sensitive to C. diff.
Diagnosis
If your doctor suspects you have a C. diff infection, they’ll take a sample of your stool and send it to the lab to test for toxins.
Diagnosing a C. diff infection isn’t always easy. There are several lab tests that can help, but no single test is perfect, says Feuerstadt.
One common test is a PCR assay test. It’s very sensitive and can detect even small amounts of C. diff bacteria, but it can’t tell whether those bacteria are causing an active infection. This matters because some people carry C. diff in their intestines without getting sick. In these cases, the bacteria are present, but not producing toxins, which can lead to unnecessary treatment.
Other tests, like enzyme immunoassays (EIAs), look for the toxins made by C. diff. “This is the only test that detects an active infection,” says Feuerstadt. The downside is that these tests are less sensitive, so they can miss some cases. For this reason, doctors often use them alongside other tests, like the glutamate dehydrogenase (GDH) antigen test.
Feuerstadt adds that it’s important that doctors use a combination of tests, along with considering your symptoms and medical history, to make a proper diagnosis.
Treatment
C. diff can exist in two different forms in the body: an active (vegetative) form and an inactive (spore) form. Treatment affects each form differently.
The active form is the bacteria that grow in your gut and release toxins. This is what causes symptoms like diarrhea. If your infection started while you were taking antibiotics, your doctor may ask you to stop those medications to see if your symptoms improve. In some cases, your body can restore balance on its own.
If your symptoms are more severe, your doctor will prescribe a different antibiotic to kill the bacteria that are producing toxins, which can ease your symptoms. In some cases, they may deliver these through an IV or directly into your colon as an enema
Common antibiotics used to treat C. diff include:
- Fidaxomicin
- Metronidazole
- Vancomycin
Feuerstadt says that on average, symptoms like diarrhea should stop within three to five days of starting an antibiotic. “It’s very important that if you’re not responding within that time, you go back to your doctor to check for other causes,” he says.
He adds that if you want your bowel habits to return to normal, it can help to go back to having the same foods you ate before the infection.
Can I take diarrhea medication if I have C. diff?
In the past, Feuerstadt says that people with C. diff infections were told not to take diarrhea medication. “We've largely debunked that,” he says. “Patients shouldn't be taking a ton of it, but in the first couple of days, if they’re miserable, they can have a couple of doses of Imodium.”
Treating Complicated or Recurring C. diff Infections
In rare cases, C. diff can lead to serious complications that require intensive care. This may include emergency surgery to remove part of the infected colon. You may need this if you have:
- Severe pain
- Organ failure
- Severe Inflammation inside your abdomen
C. diff can also stay in your body as inactive spores. Antibiotics don’t kill them, so after you finish your treatment, the spores can sometimes “wake up” and become active again. This is one reason the infection often comes back. About 25% of people who have a C. diff infection will get sick again. Those chances go up with each infection.
“When you finish antibiotics for a C. diff infection, the microbiome has to regrow,” says Feuerstadt. “It regrows successfully a lot of the time, but not always. When it doesn't, that's when a recurrence happens.”
For recurring infections, your doctor may recommend:
- Antibiotics. You may be given a different antibiotic if others haven’t worked. But these drugs may be less effective each time the infection comes back.
- Fecal microbiota transplant (FMT). This treatment uses a poop sample from a healthy donor to help restore the balance of good bacteria in your gut. It’s placed directly into your colon using special tubes that are inserted into your rectum.
- Microbiota restoration therapy (MRT). This is a newer treatment that helps rebuild healthy gut bacteria. There are currently two MRT treatments approved by the FDA — one you take as a pill and the other that goes directly into your rectum. Both are sourced from healthy human stool. MRT therapy should only be used to prevent a C. diff recurrence, not to treat an active infection.
- Probiotics. These contain good bacteria that may support gut health. There isn’t enough research to say for sure whether probiotics can prevent C. diff, but it’s generally safe to eat more foods that contain them, like probiotic yogurt and kimchi. Be sure to talk to your doctor before taking probiotic supplements, especially if you are considering other treatments. Probiotics should never be used in combination with FMT or MRT.
Preventing the Spread of C. diff
To help prevent spreading C. diff, try to:
- Wash your hands with soap and water after using the bathroom and before eating.
- Avoid touching your eyes, nose and mouth.
- Clean and disinfect surfaces in your home regularly. Products with bleach work best for getting rid of C. diff.
- If you’re caring for someone with a C. diff infection, wear protective gear like gloves and a face mask.
If you have an active C. diff infection, try to:
- Stay home for at least 48 hours after your diarrhea stops.
- Disinfect the toilet after each use.
- Wash your clothes and sheets separately from others in your household, at the highest temperature possible.
- Avoid sharing towels.
Takeaways
C. diff is a common bacterial infection that happens when the balance of good bacteria in your gut is disrupted, often after taking antibiotics. The most common symptom is diarrhea, and in some cases, the infection can come back after treatment. If you’ve recently taken antibiotics or have been in the hospital and have ongoing diarrhea, it’s important to talk to your doctor. To protect yourself and others, wash your hands regularly with soap and water and clean surfaces — especially in the bathroom with a bleach solution.
