Long-lasting C. diff infections: A threat to the gut

Dealing with diarrhea is a common experience, but for nearly 500,000 Americans annually, the persistence and recurrence of the bacterial infection known as Clostridioides difficile, or C. diff, present a significant challenge. The virulent nature of this infection can lead to severe diarrhea and inflammation of the colon, posing potential life-threatening risks.

Understanding how C. diff spreads, releases toxins, recognizing common symptoms, and identifying those most vulnerable is crucial. Dr. Jessica Allegretti, Director of the Fecal Microbiota Program at Harvard-affiliated Brigham and Women’s Hospital, offers insights into promising preventive strategies and treatments in this primer.

If you’ve ever faced prolonged or recurrent diarrhea, you’ll empathize with the impact it has on one’s well-being. This primer aims to shed light on the dynamics of C. diff, providing valuable information on its transmission, toxin release, prevalent symptoms, and the populations most susceptible to its effects. Dr. Allegretti also delves into emerging preventive measures and treatment options.

How does C. diff spread?

Clostridioides difficile (C. diff), like many bacteria, is naturally present in our stool and is carried by virtually everyone, residing on our skin and even on the soles of our shoes. In its external environment, outside the body, C. diff exists in an inactive spore form. The transition to an active state occurs when these spores are swallowed and reach the intestines.

It’s important to note that not everyone who swallows C. diff spores becomes ill. The spores only cause illness in individuals whose gut microbiome, comprising trillions of organisms in their intestines, becomes imbalanced for various reasons. When this imbalance occurs, the C. diff spores start to multiply, producing toxins that give rise to a C. diff infection.

Dr. Allegretti emphasizes, “Many of us are colonized with C. diff bacteria without any consequences. We’re swallowing C. diff spores all the time. Only under the right circumstances will the spores germinate and release a toxin. It’s the toxin that makes you sick.” Understanding the factors that contribute to this imbalance is crucial in comprehending why some individuals develop C. diff infections while others do not.

What are the symptoms of a C. diff infection?

The symptoms of a C. difficile infection can initially resemble those of various other gastrointestinal ailments, making it challenging to distinguish the infection from milder illnesses. Key symptoms to monitor include:

1. Persistent Diarrhea: Lasting three or more days, diarrhea is a prominent symptom.

2. Nausea: Feelings of queasiness may accompany the infection.

3. Fever: An elevated body temperature can be an indicator.

4. Stomach Pain or Tenderness: Discomfort or tenderness in the abdominal area may be present.

5. Appetite Loss: A noticeable decrease in appetite can occur.

Dr. Allegretti emphasizes that while C. diff isn’t something the general population should fear, individuals who have taken antibiotics should be vigilant for diarrheal symptoms after completing the antibiotic course. Diarrhea associated with antibiotics alone should typically resolve once the medication is finished. Being aware of these symptoms is crucial for prompt identification and management of a potential C. difficile infection.

Who is most vulnerable?

‘The Centers for Disease Control (CDC) provides some sobering facts about C. difficile (C. diff) infection:

1. Top Cause of Healthcare-Associated Infections: C. diff is the leading cause of healthcare-associated infections in the United States.

2. Prevalent in Hospitals and Nursing Homes: It disproportionately affects individuals in hospitals and nursing homes.

3. Mortality Rates Among Older Adults: Among individuals over the age of 65, one in 11 diagnosed with a health care-associated case of C. diff dies within a month.

4. Community-Based Infections Increasing: While health care-associated C. diff infections are stabilizing, community-based infections among the general population are on the rise.

People most susceptible to C. difficile infections include:

• Those Taking or Recently Finished Antibiotics: Individuals on antibiotics or within a month of completing antibiotic therapy are up to 10 times more likely to contract C. diff.

• Individuals with a Weakened Immune System: This includes people with cancer, organ transplant recipients, or those undergoing treatment with immunosuppressive drugs (e.g., individuals with inflammatory bowel disease or autoimmune conditions).

• Those in Close Contact with Diagnosed Cases: Having close contact with someone diagnosed with C. diff increases the risk of infection.

Dr. Allegretti emphasizes that not everyone who takes antibiotics will get C. diff, and not everyone who gets C. diff will experience recurrent infections. The likelihood is influenced by factors such as host response, gut microbiome, and individual risk factors like immunosuppression or inflammatory bowel disease. Awareness of these risk factors is crucial for preventing and managing C. difficile infections.

What prevention strategies help block the spread of C. diff?

Hospitals employ various measures to prevent C. difficile (C. diff) among patients, including stringent hand-washing requirements for staff, testing patients with new-onset diarrhea for C. diff infection, and isolating those who test positive to prevent further spread.

Outside of a hospital setting, individuals can take common sense measures to prevent this gut infection:

• 1. Thorough Hand Washing: Wash hands with soap and water after using the bathroom and before eating. This is especially important if you’ve had C. diff or have been exposed to someone with it. Alcohol-based hand sanitizer is not effective against C. diff spores.

• 2. Judicious Use of Antibiotics: Take antibiotics only when absolutely necessary and for the shortest duration possible. Advocate for oneself by questioning the need for antibiotic prescriptions, especially during cold and flu season when unnecessary prescriptions are common. Antibiotics do not kill viruses, and unnecessary use can disrupt the bacterial balance in the gut.

• 3. Consider Narrow-Spectrum Antibiotics: When antibiotics are necessary, inquire about the use of narrow-spectrum antibiotics. Broad-spectrum antibiotics, while effective against a wide range of bacteria, can disrupt the gut microbiome unnecessarily and facilitate C. diff germination. Discuss the necessity of the prescription and explore alternative options with your healthcare team.

• 4. Consider Antibiotic Type: A 2023 study in Open Forum Infectious Diseases suggests that certain antibiotics pose a higher risk for C. diff infection. Clindamycin and later-generation cephalosporin antibiotics were associated with the greatest risk, while minocycline and doxycycline were linked to the lowest risk. However, there are very few antibiotics with no risk, and decisions should be made in consultation with healthcare professionals.

Dr. Allegretti underscores the importance of dialogue with healthcare teams to make informed decisions regarding antibiotic use and to mitigate the risk of C. difficile infection.

Can probiotics help prevent or treat C. diff infection?

Probiotics, which are live microorganisms found in supplements, yogurt, and other fermented foods, play a role in maintaining gut health. Common examples include various strains of Lactobacillus and Bifidobacterium. However, despite their benefits for gut health, research indicates that probiotics have not been conclusively proven to prevent C. difficile (C. diff) or its recurrence.

Studies conducted in both mice and humans suggest that administering probiotics after a course of antibiotics may impede the recovery of the microbiome. Dr. Allegretti notes that the use of probiotics in such cases might potentially delay the restoration of a healthy microbiome.

While probiotics can offer benefits for overall gut health, their specific role in preventing or treating C. difficile infections is not yet well-established, and individuals should discuss the use of probiotics with their healthcare providers to make informed decisions based on individual health considerations.

How is C. diff infection treated?

Ironically, the treatment for C. difficile (C. diff) often begins with antibiotics, despite the infection’s association with antibiotic use. Antibiotics of choice for C. diff therapy include fidaxomicin or oral vancomycin.

However, approximately one in five individuals will experience one or more recurrences, and with each recurrence, the likelihood of further episodes increases significantly, according to Dr. Allegretti. Recurrent cases may occur because individuals haven’t effectively disinfected their homes, leaving them susceptible to reinfection with the same strain of C. diff.

For recurrent cases, fecal microbial transplants (FMT) are considered the gold standard treatment. FMT involves transferring fecal matter from a healthy donor into the patient’s gut, administered through an endoscope, enema, or oral capsule. In 2023, the FDA approved two live fecal microbiota products designed to prevent recurrent C. diff infections.

Dr. Allegretti notes, “We haven’t moved away from antibiotics yet to treat this disease, but we have a lot of preventative strategies now. It’s certainly very exciting for people struggling with C. diff infections.” The development of preventative measures, such as FMT, represents a promising advancement in managing C. difficile infections, especially for those prone to recurrences.