C. Difficile

What Is C. Diff? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Joseph Bennington-Castro
By Medically Reviewed by 
Reviewed:
Medically Reviewed

Clostridioides difficile — commonly known as C. difficile or C. diff — is a bacterium that causes diarrhea and colitis (inflammation of the colon). It’s typically found in feces and can easily contaminate food and surfaces.

Until recently, it was called Clostridium difficile, but on the basis of research regarding how the bacteria is classified, the medical community began using the new name in 2016.

About half a million people develop C. diff infections in the United States each year, according to the Centers for Disease Control and Prevention (CDC).

Many people develop it while they’re hospitalized for surgery or receiving care for other illnesses. C. diff infection most commonly affects older adults in hospitals or in long-term care facilities and usually results from the use of antibiotics. But research suggests rates of C. diff infection are increasing, and cases are being diagnosed in young, healthy individuals who haven’t used antibiotics and who haven’t been in a healthcare facility.

Since 2000, an aggressive strain of C. diff has emerged that has shown increasing resistance to certain medications. The CDC now lists C. diff as among the most urgent threats in its overall reporting on antibiotic resistance, with an estimated 223,900 hospitalizations and 12,800 deaths in the United States in 2017 due to C. diff.

Signs and Symptoms of C. Diff

Some people carry the C. diff bacteria in their intestines but never become sick. These people may even be able to spread the bacteria.

But typically, those who develop mild to moderate C. diff infection experience the following symptoms:

  • Watery diarrhea three or more times per day for two or more days
  • Fever above 100.4 degrees F (38 degrees C)
  • Loss of appetite
  • Nausea
  • Abdominal pain and cramps
Symptoms usually develop within 5 to 10 days after a person starts antibiotic treatment, though they can appear the same day you start antibiotics, or as much as two months later.

In severe cases, C. diff infection may cause:

  • Watery diarrhea up to 15 times per day
  • Dehydration
  • Swollen abdomen, with severe cramping and pain
  • Elevated heart rate
  • Fever
  • Stool containing blood or pus
  • Nausea
  • Loss of appetite or weight loss
  • Liver or kidney failure
  • Increased white blood cell count
In general, you should talk to your doctor if you’ve started antibiotic treatment and experience three or more watery stools a day for more than two days, a new fever, severe abdominal pain, or blood in your stool.

Causes and Risk Factors for C. Diff

As noted above, C. diff bacteria is found in feces. It’s also in soil, air, and water.

What’s more, this bacterium produces spores that can persist in the environment for a long time.

C. diff or its spores will get into your body if you ingest contaminated food or water or touch unwashed fingers to your mouth after handling contaminated surfaces or objects.

In healthy people, C. diff usually doesn’t cause any symptoms. The bacteria may colonize the intestines without producing any symptoms.

Yet in people with weakened immune systems or recent antibiotic use, for example, C. diff can lead to illness from the release of toxins that attack the lining of the organ.

Although people with no known risk factors can get a C. diff infection, certain things increase your risk, including the heavy use of antibiotics for the treatment of long-term infections. These antibiotics can disrupt the normal makeup of the gut microbiome — the community of microbes living in the intestines — allowing C. diff to grow out of control and cause an infection.

Antibiotics commonly associated with C. diff infections include:

Risk factors also include older age, having a severe underlying disease — such as inflammatory bowel disease (IBD) or colorectal cancer, or having a weakened immune system.

In addition, the use of proton pump inhibitors (PPIs), a type of medicine that reduces stomach acid and treats acid reflux, also may increase your risk of C. diff infection.

Your risk of C. diff infection is greater if you’ve had abdominal surgery or a gastrointestinal surgical procedure.

Furthermore, having a C. diff infection once increases your chance of having it again.

Most C. diff infections occur in people who are or who have recently been in healthcare facilities such as hospitals, nursing homes, and rehabilitation centers. In these facilities, germs spread easily, antibiotic use is common, and patients are particularly vulnerable to infection.

How Is C. Diff Diagnosed?

Because infections with C. difficile most often occur in people who are taking antibiotics or those who have recently taken them, your doctor will ask you questions about your medical history and any medications you’re taking. Your doctor may also order one or several tests, depending on your symptoms, including:

A stool test is the most common way to detect C. diff. A pathologist assesses a sample of your stool to determine whether it contains C. diff bacteria.

Blood tests can reveal high levels of white blood cells, a sign of infection, including C. diff.

A CT scan provides images of your colon and can reveal potential complications, such as a perforated intestine.

In rare instances, your doctor may want to assess your colon for signs of inflammation or other damage and perhaps rule out other causes for your symptoms. In a colonoscopy or sigmoidoscopy, a thin, flexible tube with a light on the end is inserted through the rectum, allowing your GI doctor to view the colon.

A colonoscopy allows your doctor to assess the entire colon and rectum, while a sigmoidoscopy provides images of the rectum and the lower part of the colon. Both tests can indicate whether inflammation is present, a telltale sign of a C. diff infection, among other infections or inflammatory disorders. They also allow your doctor to collect tissue samples from your colon, if needed, to further test them for bacteria.

Prognosis of C. Diff

If diagnosed and treated promptly, C. diff usually resolves quickly. The fever that often comes with the infection typically goes away within two days, and diarrhea ends in two to four days.

Some C. diff infections can become fatal in certain patients if not treated promptly, because of severe dehydration or damage to the colon or intestines.

According to the CDC, 1 in 11 people over age 65 who are diagnosed with a healthcare-associated C. diff infection die within a month.

One in 6 people will get a C. diff infection again.

Most recurrences happen one to three weeks after a person stops taking antibiotics, but some occur two to three months later.

You are at higher risk for recurrence if:

  • You’re older than 65
  • You’re taking antibiotics for another condition while being treated with antibiotics for C. diff
  • You have a severe underlying medical condition, including chronic kidney failure, inflammatory bowel disease, or chronic liver disease

Duration of C. Diff

If diagnosed and effectively treated with antibiotics, most cases of C. difficile resolve within two weeks.

Treatment and Medication Options for C. Diff

Treating C. diff infections initially requires stopping the antibiotics that led to the infection, if possible.

Depending on the severity of your infection, treatment for C. diff may include:

  • Antibiotics (different antibiotics from the ones that triggered the C. diff)
  • Surgery
  • Chronic, recurrent C. diff–infected patients may pursue a new treatment called fecal transplant

Medication Options for C. Diff

While it may sound counterintuitive (since antibiotics cause C. diff), the initial treatment for an infection usually requires taking one of three antibiotics that remain effective against the bacteria. These drugs include, yet are not limited to:

Oral vancomycin is typically the first-line antibiotic for the treatment of C. diff, while fidaxomicin (which can be cost-prohibitive) may be reserved for those with severe symptoms.

Metronidazole was a commonly used first-line treatment for C. diff. But the bacteria may have developed resistance to the drug.

Metronidazole is now recommended when access to vancomycin and fidaxomicin is limited.

Surgery for C. Diff

For people who have severe pain, organ failure, toxic megacolon, or inflammation of the lining of the abdominal wall, surgery to remove the affected portion of the colon may be the only option.

In people with recurrent C. diff, despite medication management, a fecal microbiota transplant (FMT) may be an option. In this procedure, the stool of a healthy person is transplanted into the colon of a person with C. diff infection.

Although FMT is considered experimental and is not yet approved by the U.S. Food and Drug Administration (FDA), it’s believed that the procedure restores healthy intestinal bacteria by placing the donor’s stool in your colon, using a colonoscope or nasogastric tube. Donors are screened for underlying medical conditions and infections.

Alternative and Complementary Therapies for C. Diff

To date, there’s limited research on whether alternative and complementary therapies, including home and natural remedies, are effective in treating C. diff.

Probiotics have shown some significant promise in preventing C. diff, but more research is needed to determine the optimal strain and combinations for specific patients. Probiotics are supplements — made from organisms such as bacteria and yeast — that are available as over-the-counter products, usually powders and tablets.

There’s some evidence that using probiotics while taking certain antibiotics may help prevent C. diff infections.

Researchers are still trying to determine if probiotics work in the treatment of C. diff and, if so, how.

Talk to your doctor before using probiotics or any other OTC products to treat your C. diff.

Prevention of C. Diff

Hospitals and healthcare facilities can help prevent C. diff by ensuring that staff wear gloves and wash their hands regularly with soap and water (alcohol doesn’t kill C. diff spores, so alcohol-based sanitizers aren’t effective), use disinfectant to clean rooms and equipment, and prescribe and administer antibiotics only when necessary.

To prevent your C. diff from returning, be sure to:

  • Take your C. diff medication exactly as instructed by your doctor
  • Wash your hands with soap and water after going to the bathroom, before preparing or eating food, and when they’re dirty — and encourage family to do the same
  • Clean bathroom and kitchen surfaces regularly with household detergents or disinfectants
  • Tell your doctor right away if your diarrhea returns after treatment
While rates of C. diff infection have generally been increasing, it’s interesting to note that during the COVID-19 pandemic, the prevalence of C. diff declined. A 2020 study attributed the drop to the hygiene measures and protective precautions in hospital and healthcare settings to reduce the spread of COVID-19, and suggests that continuing these measures could significantly reduce incidence of C. diff infections in the future.

Complications of C. Diff

C. diff infection can potentially lead to several serious health complications, including:

  • Dehydration (which can lead to kidney failure, if extreme)
  • Toxic megacolon
  • Colitis
  • Sepsis

The severe diarrhea caused by C. diff can lead to a significant loss of fluids and electrolytes, making it difficult for your body to function normally. In turn, this can cause blood pressure to drop to dangerously low levels.

In some cases of C. diff infection, dehydration occurs so rapidly that kidney function deteriorates, leading to kidney failure.

In addition, toxic megacolon is a rare condition that can develop after C. diff infection. If your colon is unable to expel gas and stool, it can become greatly distended, potentially causing it to rupture and allow bacteria to seep into your abdominal cavity (a condition called peritonitis).

Toxic megacolon requires emergency surgery and can be fatal if left untreated. A bowel perforation, or hole in your large intestine, is a rare complication that results from extensive damage to the lining of the organ following toxic megacolon.

Colitis is a chronic digestive disorder in which the inner lining of the colon becomes inflamed, causing pain and discomfort. C. diff infection is one of the many possible causes of colitis.

Your body’s response to an infection like C. diff can cause a potentially life-threatening condition called sepsis. To fight off an infection, your body releases chemicals into the bloodstream. But in sepsis, your body’s response to these chemicals damages multiple organ systems.

Research and Statistics: Who Has C. Diff?

An estimated half a million people are infected with C. diff in the United States annually, according to the CDC.

Women are more likely to get C. diff than men.

Age is another differentiating factor. The risk of infection is more than twice as high for seniors 65 years old and older as for any other group. It’s also up to twice as high for older adults between age 50 and 64 than it is for younger adults and children, the CDC reports.

Related Conditions and Causes of C. Diff

The bacteria that cause C. diff have, at least to date, not been linked with other health conditions. But C. diff’s symptoms may mimic those of other conditions, including:

Traveler’s diarrhea is the most common travel-related illness. It can occur anywhere but, like C. diff, it’s caused by bacteria. You’re at increased risk for exposure if you travel to places in Asia (except Japan), the Middle East, Africa, and South and Central America, according to the CDC.

Unlike C. diff, traveler’s diarrhea is rarely life-threatening, but it can be unpleasant.

Dehydration also causes dry mouth, fatigue, dizziness, headache, and muscle cramps. You may also urinate less often than you normally do or have dark urine. Most cases of dehydration are mild, and resolved by drinking lots of fluids. But severe cases may require intravenous fluids administered by a health professional.

Finally, cholera is a bacterial intestinal infection that spreads through contaminated water, particularly in regions with poor sanitation. Like C. diff, it can also cause severe diarrhea and dehydration.

Resources We Love

Centers for Disease Control and Prevention

The CDC, a trusted source for Everyday Health editors, has a comprehensive online section on C. diff, with the most current info, from treatment and prevention to life after C. diff.

Mayo Clinic

For clear, up-to-date, and detailed coverage of C. diff, visit the Mayo Clinic’s website. You can also look into participating in the clinical trials they’re conducting, which investigate new treatments and interventions for C. diff.

C. Diff Foundation

This volunteer, nonprofit advocacy organization raises awareness about C. diff and provides resources for those who have the infection and those who’ve survived it, including nutritional tips and a TeleSupport program.

Association for Professionals in Infection Control and Epidemiology (APIC)

APIC is an association for healthcare professionals that aims to prevent the spread of infection, in particular healthcare-associated infections like C. diff. Their website offers in-depth info for providers and public health workers but also has resources for patients.

Additional reporting by Brian P. Dunleavy.

Editorial Sources and Fact-Checking

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