The Intersection Between Colonization Resistance, Antimicrobial Stewardship, and Clostridium difficile

Clostridioides difficile infection: microbe-microbe interactions and live biotherapeutics

Clostridioides difficile is a gram-positive, spore-forming, obligate anaerobe that infects the colon. C. difficile is estimated to cause nearly half a million cases in the United States annually, with about 29,000 associated deaths. Unfortunately, the current antibiotic treatment is not ideal. While antibiotics can treat the infections, they also disrupt the gut microbiota that mediates colonization resistance against enteric pathogens, including C. difficile; disrupted gut microbiota provides a window of opportunity for recurrent infections. Therefore, therapeutics that restore the gut microbiota and suppress C. difficile are being evaluated for safety and efficacy. This review will start with mechanisms by which gut bacteria affect C. difficile pathogenesis, followed by a discussion on biotherapeutics for recurrent C. difficile infections.

Bibliometric analysis of peer-reviewed literature on antimicrobial stewardship from 1990 to 2019

BACKGROUND

The World Health Organization recommended the implementation of antimicrobial stewardship (AMS) in the clinical settings to minimize the development and spread of antimicrobial resistance (AMR). The current study aimed to assess global research activity on AMS as one measure for efforts dedicated to contain AMR.

METHOD

A bibliometric method was applied using Scopus. A validated search query was implemented. Bibliometric indicators and mapping were generated. The study period was from 1990 to 2019. The search query utilized the keywords "antimicrobial stewardship" or "antibiotic stewardship" in the titles or abstracts. In addition, documents with the term "restrict" or "restriction" if used with the terms "antimicrobial" or "antibiotic" were retrieved.

RESULTS

The search query returned 4402 documents. The keyword "antimicrobial stewardship" returned 2849 documents while the keyword "antibiotic stewardship" returned 1718 documents. The terms restrict/restriction and antimicrobial/antibiotics returned 209 documents. The number of publications and cumulative citations showed a steep and parallel increase in the last decade. The region of the Americas returned the most while the Eastern Mediterranean region returned the least. The United States (n = 1834, 41.7%) ranked first. Main research themes in the retrieved literature were the (1) impact of AMS on hospital length stay, (2) role of pharmacists, and (3) development of resistance of various pathogens. Clostridium difficile (n = 94) and Staphylococcus aureus (n = 76) were among the most frequently encountered author keywords. The Infection Control and Hospital Epidemiology journal ranked first (n = 245, 5.6%, h-index = 134) while documents published in the Clinical Infectious Diseases journal (h-index = 321) received the highest number of citations per document (70.7). At the institutional level, the US Centers for Disease Prevention and Control (n = 93, 2.1%) ranked first followed by the Imperial College London (n = 86, 2.0%). The main funding sponsors were the National Institute of Health. Pfizer, Merck, and Bayer pharmaceutical companies played a key role in funding AMS research. International research collaboration between developed (n = 3693, 83.9%) and developing countries (n = 759, 17.2%).

CONCLUSION

The fight against AMR is a global responsibility and implementation of AMS need to be carried out across the globe. International research collaboration between developing and developed countries should be encouraged.

Microbe-microbe interactions during Clostridioides difficile infection

Clostridioides difficile is the leading cause of hospital-acquired gastrointestinal infections and a major public health burden in the United States. C. difficile infection causes a spectrum of disease from mild diarrhea to severe complications such as pseudomembranous colitis, toxic megacolon and death. This broad range of disease is only partially explained by bacterial genetic factors, host genetics, comorbidities and previous drug exposures. Another important factor is the gut microbiome, the disruption of which results in a loss of colonization resistance to C. difficile. Here, we review how gut microbiota and their metabolites impact C. difficile virulence and influence disease.

Management of Clostridioides (formerly Clostridium) difficile infection (CDI) in solid organ transplant recipients: Guidelines from the American Society of Transplantation Community of Practice

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice address the prevention and management of Clostridium difficile infection in solid organ transplant (SOT) recipients. Clostridioides (formerly Clostridium) difficile infection (CDI) is among the most common hospital acquired infections. In SOT recipients, the incidence of CDI varies by type and number or organs transplanted. While a meta-analysis of published literature found the prevalence of postoperative CDI in the general surgical population to be approximately 0.51%, the prevalence of CDI that is seen in the solid organ transplant population ranges from a low of 3.2% in the pancreatic transplant population to 12.7% in those receiving multiple organ transplants. There are no randomized, controlled trials evaluating the management of CDI in the SOT population. Herein is a review and summary of the currently available literature that has been synthesized into updated treatment guidelines for the management of CDI in the SOT population.

When not to start antibiotics: avoiding antibiotic overuse in the intensive care unit

BACKGROUND

Most intensive care unit (ICU) patients receive broad-spectrum antibiotics. While lifesaving in some, in others these treatments may be unnecessary and place patients at risk of antibiotic-associated harms.

OBJECTIVES

To review the literature exploring how we diagnose infection in patients in the ICU and address the safety and utility of a 'watchful waiting' approach to antibiotic initiation with selected patients in the ICU.

SOURCES

A semi-structured search of PubMed and Cochrane Library databases for articles published in English during the past 15 years was conducted.

CONTENT

Distinguishing infection from non-infectious mimics in ICU patients is uniquely challenging. At present, we do not have access to a rapid point-of-care test that reliably differentiates between individuals who need antibiotics and those who do not. A small number of studies have attempted to compare early aggressive versus conservative antimicrobial strategies in the ICU. However, this body of literature is small and not robust enough to guide practice.

IMPLICATIONS

This issue will not likely be resolved until there are diagnostic tests that rapidly and reliably identify the presence or absence of infection in the ICU population. In the meantime, prospective trials that identify clinical situations wherein it is safe to delay or withhold antibiotic initiation in the ICU until the presence of an infection is proven are warranted.