Clostridium difficile Infections

1. Basic Facts About Clostridium difficile and Clostridium difficile infection (CDI)

Clostridium difficile (C. difficile) is an anaerobic, gram-positive bacterium. It can exist in two forms: a dormant spore that has a tough protein coat, and a vegetative form that results from spore germination. Because of the anaerobic nature of the bacteria, the dormant spore is the infectious and transmissible form.1 C. difficile was first detected in the lower intestinal tract of newborns in 1935, but it is not considered to be a normal commensal bacterium of the gut.2 It was not until 1978 that it was understood to cause the disease commonly known as Clostridium difficile infection (CDI). C. difficile is a common bacteria and has been isolated from soil, houses, shops and healthcare facilities.3, 4

How Is CDI Caused?

C. difficile causes pseudomembranous colitis, a severe inflammatory infection of the colon that is commonly known as CDI. In general, two conditions — colonization with C. difficile and exposure to antibiotics — are necessary prerequisites for infection to develop. In healthy individuals, C. difficile spores may colonize the gut, coexisting with a diverse range of bacteria — known as commensals — that make up the microbiota. The diverse commensal bacteria form a mucus layer on the epithelial cells of the intestinal tract.

However, following antibiotic treatment, the normal gut microbiota is disrupted and many commensal bacteria are killed. In this situation, microorganisms such as C. difficile may not be affected by the antibiotic and can proliferate. As a result, C. difficile spores can attach to the epithelial wall of the small intestine, germinate into the vegetative state, and reproduce. This causes the release of two exotoxins — toxin A and toxin B — which attack the epithelial cells and cause mucosal damage.5 Studies suggest that toxin B is responsible for C. difficile virulence.6, 7

The susceptibility of the patient or the virulence of the C. difficile strain may also play a role in determining whether the infection develops. Some people who experience colonization and exposure to antibiotics may become only asymptomatically colonized.8

While most antibiotics are suspected of being a trigger for the development of CDI, the risk appears to be higher for specific classes of antibiotics such as cephalosporins, fluoroquinolones and clindamycin. In recent outbreaks, the fluoroquinolone class of antibiotics has been implicated.9, 10

Who Is Affected by CDI?

CDI can affect people of all ages. However, the risk of developing CDI is greatest in patients over 65, those with chronic health conditions and comorbidities such as diabetes, those undergoing gastrointestinal surgery, those who are immunocompromised and those who have a history of prior antibiotic use.11 Additionally, those who are subject to long stays in healthcare settings such as hospitals, nursing homes and long-term care facilities are also at increased risk.

CDI Symptoms

Depending on the virulence of the infecting C. difficile strain, the toxins can cause illness ranging from mild diarrhea to pseudomembranous colitis. In all cases, the major symptom of CDI is diarrhea. Mild cases may experience only this symptom, while severe cases can include severe abdominal cramping, blood or pus in the stool, nausea, a swollen abdomen, kidney failure and an increased white blood cell count.12 A significant proportion of patients require a colectomy — removal of the colon. Severe infection can lead to sepsis and death.

How Is CDI Treated?

CDI is treated by the administration of antibiotics that can kill C. difficile bacteria. For milder cases of CDI, metronidazole is the most commonly prescribed antibiotic. For more severe cases, vancomycin or fidaxomicin administered orally will most likely be prescribed. A course of treatment usually lasts for a minimum of 10 days. More recently, fecal transplants — transplants of stool from healthy people — have been used to treat CDI with some success, although the long-term safety has not been established.12

What Is Recurrent CDI?

For a significant proportion of CDI patients, recurrent disease remains a risk. Recurrent disease occurs in around 20% of patients, can occur as little as one to two weeks after resolution of the initial infection, and may occur multiple times. The first recurrence is usually treated with the same antibiotics that were used to treat the initial infection. Multiple recurrent infections are usually treated with vancomycin or fidaxomicin.13

2. The Burden of Clostridium difficile Infection

CDI is one of the most common infections found in hospitals and long-term care facilities. In fact, C. difficile has been a possible factor in hundreds of deaths in Ontario hospitals alone.13

These types of infections can very easily be transmitted within a hospital, especially when infection prevention and control measures aren’t followed.14

That can put patients, visitors and hospital staff in the very unfortunate position of being at risk for contracting C. difficile. The Canadian Patient Safety Institute warns that this harmful bacterium can produce toxins that damage the lining of the intestines and lead to serious symptoms that range from diarrhea to death.15

3. Transmission of Clostridium difficile

There are two main reservoirs of C. difficile: infected or colonized patients, and inanimate surfaces and objects in the healthcare environment. Transmission occurs through the fecal-oral route. As C. difficile spores are found in the gastrointestinal tract and because diarrhea is associated with CDI, the spores are shed in the stool of CDI patients and those who are asymptomatically colonized with C. difficile. Shed spores can contaminate healthcare workers’ hands and shared equipment such as thermometers, infusion pumps, mobile devices and commodes, and are then easily transmitted between patients by ingestion of spores after a contaminated surface is touched.16, 17 Studies on the survival of C. difficile on hard surfaces such as those found in the healthcare environment have shown that while the vegetative form dies within 24 hours, C. difficile spores can persist for months.18 This long survival period of the spores increases the risk of transmission from a contaminated surface that has not been properly cleaned and disinfected.

4. Preventing C. difficile Transmission: The Importance of Surface Disinfection and Hand Hygiene

As with any infectious disease, frequent hand hygiene is the most effective way of preventing the transmission of healthcare associated infections. Hand washing with soap and water is important during C. difficile outbreaks and is one of the best defences against further spread of the bacteria.

If you do not have access to soap and water, frequent use of alcohol-based hand rubs is encouraged. Most healthcare facilities provide alcohol-based hand rubs at entrances. Be sure to use them, but be aware that they are less effective than washing with soap and water as they do not destroy C. difficile spores.

If you work in or visit a hospital or long-term healthcare facility, wash your hands often preferably with soap and water, especially after using the toilet. Gloves should be worn when caring for a patient with C. difficile infection or if in contact with his/her environment. Use a new pair of gloves when caring for each patient. Be sure to wash your hands with soap and water after removing your gloves.

When antibiotics are prescribed, follow your doctor, pharmacist, or healthcare provider’s instructions and the directions on the label. Keep taking the antibiotics as prescribed to kill all of the C. difficile bacteria.

If you have concerns about C. difficile and medication you are currently using, talk to your doctor, pharmacist, or healthcare provider.14

Surface Disinfection

C. difficile spores are resistant to many common disinfectants, so a Health Canada-registered disinfectant with a claim to inactivate C. difficile spores should be used. Rooms of CDI patients should be cleaned and disinfected daily, with particular attention paid to high-touch areas such as bed rails, bedside furniture, commodes, light switches and doorknobs, mobile devices, and medical equipment and monitors. Particular attention should also be paid to items shared between patients.

Hand Hygiene

Appropriate hand hygiene techniques should be practiced by patients, healthcare staff and visitors. Hands should be washed with soap and water for at least 30 seconds, followed by thorough drying with paper towels. Alcohol-based hand sanitizers do not inactivate C. difficile and should not be used when soap and water are available.

How Family Members and Visitors Can Help

As part of an education program, family and visitors should be educated about how they can help prevent C. difficile transmission. This includes being provided with information on the disease and transmission, the correct way to wash hands, how to identify visitors who may be at greater risk for acquiring C. difficile and the steps they can take once patients are discharged, such as cleaning and disinfecting homes, not sharing towels or hygiene products, and best practices for laundering.

5. CloroxPro Disinfectants with Health Canada-Approved Claims Against C. difficile

CloroxPro offers a range of bleach-based disinfectants that have an Health Canada-registered claim against C. difficile on hard, nonporous surfaces.

Product Product details C. difficile
contact time
Clorox Healthcare® Fuzion® Cleaner Disinfectant Ready-to-use spray; 0.39% sodium hypochlorite 1 min
Clorox Healthcare® Bleach Germicidal Disinfectants Wipes Ready-to-use wipes; 0.55% sodium hypochlorite 3 min
Clorox Healthcare® Bleach Germicidal Cleaner Ready-to-use cleaner-disinfectant
in a spray bottle or pull-top; 0.65%
sodium hypochlorite		 3 min
Clorox® Germicidal Bleach 8.25% sodium hypochlorite; dilute 1:14 to
make a 0.59% solution		 5 min

References

1. Paredes-Sabja D, Shen A, Sorg JA. Clostridium difficile spore biology: sporulation, germination, and spore structural proteins. Trends Microbiol. 2014;22(7): 406–416.
2. Leffler DA, Lamont JT. Clostridium difficile Infection. N Engl J Med 2015;372:1539-1548
3. Alam MJ, Walk ST, Endres BT, et al. Community environmental contamination of toxigenic Clostridium difficile. Open Forum Infect Dis 2017 Feb 10;4(1).
4. Alam MJ, Anu A, Walk ST, Garey KW. Investigation of potentially pathogenic Clostridium difficile contamination in household environs. Anaerobe 2014;27:31-3.
5. Reeves AE, Theriot CM, Bergin IL, et al. The interplay between microbiome dynamics and pathogen dynamics in a murine model of Clostridium difficile Infection. Gut Microbes 2011;2:145-158.
6. Lyras D, O’Connor JR, Howarth PM, et al. Toxin B is essential for virulence of Clostridium difficile. Nature 2009;458:1176-1179.
7. Sambol SP, Tang JK, Merrigan MM, Johnson S, Gerding DN. Infection of hamsters with epidemiologically important strains of Clostridium difficile. J Infect Dis 2001;183:1760-1766.
8. Johnson S, Gerding DN. Clostridium difficile-associated diarrhea. Clin Infect Dis 1998;26:1027-1034.
9. Muto CA, Pokrywka M, Shutt K, et al. A large outbreak of Clostridium difficile-associated disease with an unexpected proportion of deaths and colectomies at a teaching hospital following increased fluoroquinolone use. Infect Control Hosp Epidemiol 2005;26:273-280.
10. Gaynes R, Rimland D, Killum E, et al. Outbreak of Clostridium difficile infection in a long-term care facility: Association with gatifloxacin use. Clin Infect Dis 2004;38:640-645
11. Mayo Clinic. C. difficile infection. https://www.mayoclinic.org/diseases-conditions/c-difficile/symptoms-causes/syc-20351691. Accessed December 15, 2017.
12. Centers for Disease Control and Prevention. Clostridium difficile infection information for patients. https://www.cdc.gov/hai/organisms/cdiff/cdiff-patient.html. Accessed December 15, 2017.
13. The Globe and Mail. Powell N, Walters J. https://www.theglobeandmail.com/news/national/c-difficile-possible-factor-in-463-ontario-hospital-deaths/article1056968/. Accessed March 27, 2019.
14. Government of Canada. Public Health Agency of Canada. Fact Sheet – Clostridium difficile. https://www.canada.ca/en/public-health/services/infectious-diseases/fact-sheet-clostridium-difficile-difficile.html. Accessed January 21, 2019.
15. Canadian Patient Safety Institute. Clostridium difficile. https://www.patientsafetyinstitute.ca/en/Topic/Pages/Clostridium-difficile.aspx. Accessed January 21, 2019.
16. Shaughnessy MK, Micielli RL, Depestel DD, et al. Evaluation of hospital room assignment and acquisition of Clostridium difficile infection. Infect Control Hosp Epidemiol 2011;32:201-206.
17. McFarland LV, Mulligan ME, Kwok RY, Stamm WE. Nosocomial acquisition of Clostridium difficile infection. N Engl J Med 1989;320:204-210.
18. Kramer, A.; Schwebke, I.; Kampf, G. How long do nosocomial pathogens persist on inanimate surfaces? A systematic review. BMC Infect Dis 2006(6):130.