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Antimicrobial Resistance

Quick Facts! 

  • Antimicrobial resistance (AMR) is a serious threat to global public health and threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi.

  • The cost of healthcare for patients with resistant infections is higher, and these patients are more likely to spread the infection, as well as suffer from severe illness, disability, and death.

  • AMR occurs naturally in microbes, but by using antibiotics inappropriately, everyday citizens are contributing to the spread of resistance across the globe

  • AMR in C. difficile infection has been worsened by the widespread use of certain types of antibiotics, and resistant C. difficile strains have been linked to more severe infections, increased rates of recurrences and high death rates

What are antibiotics?

So, what exactly are antibiotics? Simply put, they are drugs that directly kill bacteria or stop its growth so that your body’s immune system can eliminate them. In medicine, antibiotics are prescribed to when a patient has a bacterial infection and can come in many different forms: pills, liquids, injections, and ointments. Antibiotics are also referred to as antimicrobials, which are a broader umbrella term that refers to drugs that target microbes (which include bacteria, fungi, and viruses) that cause infection (1).

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On the rise: AMR and C.difficile 

As we have discussed, antibiotics are used to treat or prevent bacterial infections. But in the case of a C. difficile infection (CDI), it can actually be responsible for causing it (27). The use of antibiotics that are not meant to be used for C. diff can disrupt the protective bacteria in the gut microbiome and allow for the C. diff bacteria to proliferate (27). In fact, use of many antibiotics like; ampicillin, amoxicillin, cephalosporins, clindamycin, and fluoroquinolones have been associated with CDI (28). Depending on the severity, treatment of CDI usually involves antibiotics such as metronidazole, vancomycin, and fidaxomicin which act against C. diff (29, 30). While metronidazole and vancomycin remain effective as first line antibiotics used for treating CDI, the number of C. diff strains resistant to these therapeutics is increasing (28). In the past decade, failed treatment of CDI around the world with metronidazole has significantly increased (28). 


The worldwide spread of C. diff is changing due to the emergence of these highly effective bacteria which can cause more severe infections, increased rates of recurrences and mortality (30). We know that new C. diff strains are becoming resistant to not just one, but multiple antibiotics like the deadly C. difficile ribotype 027 strain which is resistant to several therapeutics (31, 32). Newer strains of antibiotic-resistant C. diff emerging are a huge concern when considering CDI treatment, as currently available antibiotics will not be efficient (31, 32). Antibiotic resistance to C. diff can lead to unwanted clinical outcomes and even potential treatment failure (31). 

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References

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