Consequences of Clostridium difficile infection: understanding the healthcare burden

Discovery and Structure-Activity Relationship of Cadazolid: A First-In-Class Quinoxolidinone Antibiotic for the Treatment of Clostridioides difficile Infection

Clostridioides difficile (C. difficile) is one of the leading causes of healthcare-associated infections worldwide. The increasing incidence of strains resistant to currently available therapies highlights the need for alternative treatment options with a novel mode of action. Oxazolidinones that are connected to a quinolone moiety with a pyrrolidine linker, such as compound 1, are reported to exhibit potent broadspectrum antibacterial activity. In an effort to optimize this class of compounds for the treatment of C. difficile infection (CDI), we have identified cadazolid (9), a first-in-class quinoxolidinone antibiotic, which is a potent inhibitor of C. difficile protein synthesis. In order to achieve narrow-spectrum coverage of clinically most relevant strains without affecting the gut microbiota, an emphasis was placed on abolishing activity against commensals of the intestinal microbiome while retaining good coverage of pathogenic C. difficile, including hypervirulent and epidemic strains.

Exploring the Toxin-Mediated Mechanisms in Clostridioides difficile Infection

Clostridioides difficile infection (CDI) is the leading cause of nosocomial antibiotic-associated diarrhea, and colitis, with increasing incidence and healthcare costs. Its pathogenesis is primarily driven by toxins produced by the bacterium C. difficile, Toxin A (TcdA) and Toxin B (TcdB). Certain strains produce an additional toxin, the C. difficile transferase (CDT), which further enhances the virulence and pathogenicity of C. difficile. These toxins disrupt colonic epithelial barrier integrity, and induce inflammation and cellular damage, leading to CDI symptoms. Significant progress has been made in the past decade in elucidating the molecular mechanisms of TcdA, TcdB, and CDT, which provide insights into the management of CDI and the future development of novel treatment strategies based on anti-toxin therapies. While antibiotics are common treatments, high recurrence rates necessitate alternative therapies. Bezlotoxumab, targeting TcdB, is the only available anti-toxin, yet limitations persist, prompting ongoing research. This review highlights the current knowledge of the structure and mechanism of action of C. difficile toxins and their role in disease. By comprehensively describing the toxin-mediated mechanisms, this review provides insights for the future development of novel treatment strategies and the management of CDI.

A Comparison of Currently Available and Investigational Fecal Microbiota Transplant Products for Recurrent Clostridioides difficile Infection

Clostridioides difficile infection (CDI) is an intestinal infection that causes morbidity and mortality and places significant burden and cost on the healthcare system, especially in recurrent cases. Antibiotic overuse is well recognized as the leading cause of CDI in high-risk patients, and studies have demonstrated that even short-term antibiotic exposure can cause a large and persistent disturbance to human colonic microbiota. The recovery and sustainability of the gut microbiome after dysbiosis have been associated with fewer CDI recurrences. Fecal microbiota transplantation (FMT) refers to the procedure in which human donor stool is processed and transplanted to a patient with CDI. It has been historically used in patients with pseudomembranous colitis even before the discovery of Clostridioides difficile. More recent research supports the use of FMT as part of the standard therapy of recurrent CDI. This article will be an in-depth review of five microbiome therapeutic products that are either under investigation or currently commercially available: Rebyota (fecal microbiota, live-jslm, formerly RBX2660), Vowst (fecal microbiota spores, live-brpk, formerly SER109), VE303, CP101, and RBX7455. Included in this review is a comparison of the products' composition and dosage forms, available safety and efficacy data, and investigational status.

Economic Burden of Clostridioides difficile Infection in European Countries

Clostridioides difficile infection (CDI) remains a considerable challenge to healthcare systems worldwide. Although CDI represents a significant burden on healthcare systems in Europe, few studies have attempted to estimate the consumption of resources associated with CDI in Europe. The reported extra costs attributable to CDI vary widely according to the definitions, design, and methodologies used, making comparisons difficult to perform. In this chapter, the economic burden of healthcare facility-associated CDI in Europe will be assessed, as will other less explored areas such as the economic burden of recurrent CDI, community-acquired CDI, pediatric CDI, and CDI in outbreaks.

New treatment approaches for Clostridioides difficile infections: alternatives to antibiotics and fecal microbiota transplantation

Clostridioides difficile causes a range of debilitating intestinal symptoms that may be fatal. It is particularly problematic as a hospital-acquired infection, causing significant costs to the health care system. Antibiotics, such as vancomycin and fidaxomicin, are still the drugs of choice for C. difficile infections, but their effectiveness is limited, and microbial interventions are emerging as a new treatment option. This paper focuses on alternative treatment approaches, which are currently in various stages of development and can be divided into four therapeutic strategies. Direct killing of C. difficile (i) includes beside established antibiotics, less studied bacteriophages, and their derivatives, such as endolysins and tailocins. Restoration of microbiota composition and function (ii) is achieved with fecal microbiota transplantation, which has recently been approved, with standardized defined microbial mixtures, and with probiotics, which have been administered with moderate success. Prevention of deleterious effects of antibiotics on microbiota is achieved with agents for the neutralization of antibiotics that act in the gut and are nearing regulatory approval. Neutralization of C. difficile toxins (iii) which are crucial virulence factors is achieved with antibodies/antibody fragments or alternative binding proteins. Of these, the monoclonal antibody bezlotoxumab is already in clinical use. Immunomodulation (iv) can help eliminate or prevent C. difficile infection by interfering with cytokine signaling. Small-molecule agents without bacteriolytic activity are usually selected by drug repurposing and can act via a variety of mechanisms. The multiple treatment options described in this article provide optimism for the future treatment of C. difficile infection.

Trends in the epidemiology of Clostridioides difficile infection in Germany

PURPOSES

Despite reports of a declining incidence over the last decade, Clostridioides difficile infection (CDI) is still considered the most important healthcare-associated causes of diarrhea worldwide. In Germany, several measures have been taken to observe, report, and influence this development. This report aims to analyze the development of hospital coding for CDI in Germany over the last decade and to use it to estimate the public health burden caused by CDI.

METHODS

Reports from the Institute for Hospital Remuneration Systems, German Federal Statistical Office (DESTATIS), the Robert-Koch-Institute (RKI), Saxonian authorities and hospital quality reports during 2010-2021 were examined for CDI coding and assessed in a structured expert consultation. Analysis was performed using 2019 versions of Microsoft Excel® and Microsoft Access®.

RESULTS

Peaks of 32,203 cases with a primary diagnosis (PD) of CDI and 78,648 cases with a secondary diagnosis (SD) of CDI were observed in 2015. The number of cases had decreased to 15,412 PD cases (- 52.1%) and 40,188 SD cases (- 48.9%) by 2021. These results were paralleled by a similar decline in notifiable severe cases. However, average duration of hospitalization of the cases remained constant during this period.

CONCLUSIONS

Hospital coding of CDI and notification to authorities has approximately halved from 2015 to 2021. Potential influential factors include hospital hygiene campaigns, implementation of antibiotic stewardship programs, social distancing due to the COVID-19 pandemic, and a decrease in more pathogenic subtypes of bacteria. Further research is necessary to validate the multiple possible drivers for this development.

Role of Fecal Microbiota Transplantation in Managing Clostridium Difficile Infection and Inflammatory Bowel Disease: A Narrative Review

Fecal microbiota transplantation (FMT) has been emerging as an alternate treatment modality in the management of patients with dysbiosis by restoring abnormal gut microbiota composition through the transplantation of normal fecal microbiota from healthy donors. This technique has lately gained a lot of attention in the treatment of recurrent or refractory Clostridium difficile infection (CDI) owing to its high success rates combined with its favorable safety profile. FMT has also been attracting the interest of clinicians as a new treatment option for inflammatory bowel diseases (IBD). Here, we reviewed most of the recent advancements in the use of FMT for CDI as well as its use in the treatment of IBD.

Does clinician-initiated Clostridioides difficile testing improve outcomes of patients with Clostridioides Difficile infection?

BACKGROUND

Clostridioides difficile (C. difficile) is a common hospital-acquired infection which can lead to major implications for patients and our health care system. In this study, we examine a policy change at a single-site Veterans Affairs Healthcare system that allowed bedside nurses to order C. difficile testing in addition to physicians on the time to obtain test results and initiate treatment.

METHODS

The time to receive results and initiate treatment were analyzed before and after the policy change, and between physicians and nurses using descriptive statistics and paired student t-tests. Variables associated with lower ordering times were also analyzed using logistic regression while adjusting for patient admission location and length of inpatient hospital stay.

RESULTS

The difference in time to obtain the result both before and after the policy change and between ordering provider type were both statistically significant (P < .05). In unadjusted models, nurses were associated with faster test results compared to physicians (OR (95% CI) 1.72 (1.45-2.05).

CONCLUSIONS

Allowing bedside nurses more autonomy to order the stool sample significantly decreased the amount of time to receive the results, potentially decreasing the risk of additional infections among patients and decreasing the economic burden on the hospital.

Clostridioides difficile Near-Patient Testing Versus Centralized Testing: A Pragmatic Cluster Randomized Crossover Trial

BACKGROUND

Management of suspected Clostridioides difficile infection (CDI) in the hospital setting typically results in patient isolation, laboratory testing, infection control, and presumptive treatment. We investigated whether implementation of rapid near-patient testing (NPT) reduced patient isolation time, hospital length of stay (LOS), antibiotic usage, and cost.

METHODS

A 2-period pragmatic cluster randomized crossover trial was conducted. Thirty-nine wards were randomized into 2 study arms. The primary outcome measure was effect of NPT on patient isolation time using a mixed-effects generalized linear regression model. Secondary outcomes examined were hospital LOS and antibiotic therapy based on a negative binomial regression model. Natural experiment (NE), intention-to-treat (ITT), and per-protocol (PP) analyses were conducted.

RESULTS

During the entire study period, a total of 656 patients received NPT for CDI and 1667 received standard-of-care testing. For the primary outcome, a significant decrease of patient isolation time with NPT was observed (NE, 9.4 hours [P < .01]; ITT, 2.3 hours [P < .05]; PP, 6.7 hours [P < .1]). A significant reduction in hospital LOS was observed with NPT for short stay (NE, 47.4% [P < .01]; ITT, 18.4% [P < .01]; PP, 34.2% [P < .01]). Each additional hour delay for a negative result increased metronidazole use (24 defined daily doses per 1000 patients; P < .05) and non-CDI-treating antibiotics by 70.13 mg (P < .01). NPT was found to save 25.48 US dollars per patient when including test cost to the laboratory and patient isolation in the hospital.

CONCLUSIONS

This pragmatic cluster randomized crossover trial demonstrated that implementation of CDI NPT can contribute to significant reductions in isolation time, hospital LOS, antibiotic usage, and healthcare cost. Clinical Trials Registration. NCT03857464.

Emerging applications of phage therapy and fecal virome transplantation for treatment of Clostridioides difficile infection: challenges and perspectives

Clostridioides difficile, which causes life-threatening diarrheal disease, is considered an urgent threat to healthcare setting worldwide. The current standards of care solely rely on conventional antibiotic treatment, however, there is a risk of promoting recurrent C. difficile infection (rCDI) because of the emergence of antibiotic-resistant strains. Globally, the alarming spread of antibiotic-resistant strains of C. difficile has resulted in a quest for alternative therapeutics. The use of fecal microbiota transplantation (FMT), which involves direct infusion of fecal suspension from a healthy donor into a diseased recipient, has been approved as a highly efficient therapeutic option for patients with rCDI. Bacteriophages or phages are a group of viruses that can infect and destroy bacterial hosts, and are recognized as the dominant viral component of the human gut microbiome. Accumulating data has demonstrated that phages play a vital role in microbial balance of the human gut microbiome. Recently, phage therapy and fecal virome transplantation (FVT) have been introduced as promising alternatives for the treatment of C. difficile -related infections, in particular drug-resistant CDI. Herein, we review the latest updates on C. difficile- specific phages, and phage-mediated treatments, and highlight the current and future prospects of phage therapy in the management of CDI.

Budget Impact Analysis of Adopting a One-Step Nucleic Acid Amplification Testing (NAAT) Alone Diagnostic Pathway for Clostridioides difficile in Japan Compared to a Two-Step Algorithm with Glutamate Dehydrogenase/Toxin Followed by NAAT

Clostridioides difficile infection (CDI) is a major healthcare-associated infection that leads to a significant health economic burden in Japan. Using a decision tree model, we evaluated the budget impact of adopting a one-step nucleic acid amplification test (NAAT) alone pathway compared to a two-step diagnostic algorithm with glutamate dehydrogenase (GDH) and toxin antigen, followed by NAAT. The analysis was conducted from the government payer's perspective for 100,000 symptomatic, hospitalized adults requiring a CDI diagnostic test. One-way sensitivity analysis was conducted for all data inputs. The NAAT alone strategy costed JPY 225,886,360 (USD 2,424,714) more, but was more effective, resulting in 1749 more patients accurately diagnosed and 91 fewer deaths compared to the two-step algorithm. Additionally, the NAAT alone pathway costed JPY 26,146 (USD 281) less per true positive CDI diagnosed. The total budget impact, and cost per CDI diagnosed was most sensitive to GDH sensitivity in one-way sensitivity analysis, where a lower GDH sensitivity resulted in greater cost savings with the NAAT alone pathway. Findings from this budget impact analysis can guide the adoption of a NAAT alone pathway for CDI diagnosis in Japan.

Real-world Use of Bezlotoxumab and Fecal Microbiota Transplantation for the Treatment of Clostridioides difficile Infection

Background

We aimed to describe the frequency of use and effectiveness of bezlotoxumab (BZX) and fecal microbiota transplantation (FMT) in patients with Clostridioides difficile infection (CDI) in real-world practice.

Methods

This was a retrospective study conducted in a university hospital in which adult patients treated with BZX or FMT from January 2018 to April 2021 were included. The primary objective was to evaluate the effectiveness of BZX and FMT in preventing early (within 8 weeks) and late (within 1 year) CDI recurrences (rCDI). A multivariate analysis of risk factors for early recurrence was performed.

Results

Of 1377 consecutive CDI episodes, 117 (8.5%) received BZX or FMT, with full information available for 100 of the episodes: 51 received BZX, and 49 received FMT. BZX was used mostly in immunosuppressed patients (66.7%) and in first episodes or first recurrences in 70.6% of the cases. FMT was prescribed only in CDI recurrences. Despite the different conditions of the patients, there were no significant differences between BZX and FMT in preventing early rCDI (19.6% vs 24.5%; P = .55) or late rCDI (9.8% vs 18.4%; P = .31). In the multivariate analysis, risk factors for recurrence were presence of ≥2 previous rCDI episodes (odds ratio [OR], 2.90; 95% CI, 1.03-8.63) and use of non-CDI antibiotics (OR, 3.45; 95% CI, 1.24-9.57).

Conclusions

BZX and FMT were infrequently used in real-world practice. Both treatments had similar effectiveness in preventing CDI recurrence despite their application to different populations.

A comparison of culture methods and polymerase chain reaction in detecting Clostridioides difficile from hospital surfaces

Introduction. Environmental surveillance for Clostridioides difficile is challenging. There are no internationally agreed recommendations on which method should be used when environmental surveillance is undertaken.Aim. To compare the detection of C. difficile by RT-PCR to culture-based methods and to determine which is more sensitive and specific in the clinical environment.Methods. Forty-four near-patient areas of C. difficile-positive patients were sampled using contact plates and moistened flocked swabs.Results. Detection using moistened flocked swabs followed by RT-PCR or culture detected more C. difficile than contact plates. The sensitivity and specificity of a RT-PCR assay for tcdB compared to the culture methods was 76 and 91 %, respectively.Conclusion. Despite the lower sensitivity and specificity, RT-PCR could potentially offer a more rapid and practical alternative.

Clostridium difficile colitis portends poor outcomes in lower extremity orthopaedic trauma surgery

INTRODUCTION

Clostridium difficile is the most common cause of healthcare-associated infectious diarrhea and colitis, and carries the potential for high morbidity, particularly in frail patient populations. The purpose of this study was to utilize a large nationally representative database in order to report 1.) the incidence of CDC in patients with operative lower extremity fractures, 2.) risk factors for the development of CDC, 3.) the association of CDC with length of stay (LOS), readmission, and 30-day mortality rates.

METHODS

The ACS-NSQIP (2015-2019) was queried for patients who underwent surgical fixation of lower extremity fractures. A backward elimination multivariate regression model was used to identify risk factors for CDC. Chi squared and multivariate regression that controlled for preoperative variables and comorbidities were used to compare outcomes in patients with and without CDC.

RESULTS

95,532 patients were included, 681 (0.71%) of whom developed CDC. Risk factors for CDC were advanced age, ASA class ≥ 3, smoking, dialysis, anemia, hypoalbuminemia, preoperative SIRS, preoperative wound infections, preoperative sepsis, and the use of spinal anesthesia or MAC/IV sedation. Patients with CDC had significantly increased 30-day mortality rates (10.6% vs 4.4%; OR 1.80, 95% CI 1.41-2.31), readmission (34.2% vs 7.5%; OR 5.13, 95% CI 4.36-6.05, and length of stay (7.5 days vs 5.3 days) compared to patients without CDC.

CONCLUSION

The incidence of CDC in lower extremity orthopedic trauma patients was 0.71%. An occurrence of CDC was associated with approximately a 2.5 times increase in 30-day mortality, five times the readmission rate, and a longer hospital stay compared to patients without CDC. Mitigating the spread of c. diff through improved antibiotic stewardship and prompt treatment of CDC is paramount to decreasing the burden this infection imposes on orthopedic trauma patients and the healthcare system.

Role of the Spore Coat Proteins CotA and CotB, and the Spore Surface Protein CDIF630_02480, on the Surface Distribution of Exosporium Proteins in Clostridioides difficile 630 Spores

Clostridioides difficile is Gram-positive spore-former bacterium and the leading cause of nosocomial antibiotic-associated diarrhea. During disease, C. difficile forms metabolically dormant spores that persist in the host and contribute to recurrence of the disease. The outermost surface of C. difficile spores, termed the exosporium, plays an essential role in interactions with host surfaces and the immune system. The main exosporium proteins identified to date include three orthologues of the BclA family of collagen-like proteins, and three cysteine-rich proteins. However, how the underlying spore coat influences exosporium assembly remains unclear. In this work, we explore the contribution of spore coat proteins cotA and cotB, and the spore surface protein, CDIF630_02480, to the exosporium ultrastructure, formation of the polar appendage and the surface accessibility of exosporium proteins. Transmission electron micrographs of spores of insertional inactivation mutants demonstrate that while cotB contributes to the formation of thick-exosporium spores, cotA and CDIF630_02480 contribute to maintain proper thickness of the spore coat and exosporium layers, respectively. The effect of the absence of cotA, cotB and CDIF630_02480 on the surface accessibility of the exosporium proteins CdeA, CdeC, CdeM, BclA2 and BclA3 to antibodies was affected by the presence of the spore appendage, suggesting that different mechanisms of assembly of the exosporium layer might be implicated in each spore phenotype. Collectively, this work contributes to our understanding of the associations between spore coat and exosporium proteins, and how these associations affect the assembly of the spore outer layers. These results have implications for the development of anti-infecting agents targeting C. difficile spores.

Systematic Review and Meta-Analysis on the Frequency of Antibiotic-Resistant Clostridium Species in Saudi Arabia

Clostridium is a genus comprising Gram-positive, rod-shaped, spore-forming, anaerobic bacteria that cause a variety of diseases. However, there is a shortage of information regarding antibiotic resistance in the genus in Saudi Arabia. This comprehensive analysis of research results published up until December 2021 intends to highlight the incidence of antibiotic resistance in Clostridium species in Saudi Arabia. PubMed, Google Scholar, Web of Science, SDL, and ScienceDirect databases were searched using specific keywords, and ten publications on antibiotic resistance in Clostridium species in Saudi Arabia were identified. We found that the rates of resistance of Clostridium difficile to antibiotics were as follows: 42% for ciprofloxacin, 83% for gentamicin, 28% for clindamycin, 25% for penicillin, 100% for levofloxacin, 24% for tetracycline, 77% for nalidixic acid, 50% for erythromycin, 72% for ampicillin, and 28% for moxifloxacin; whereas those of C. perfringens were: 21% for metronidazole, 83% for ceftiofur, 39% for clindamycin, 59% for penicillin, 62% for erythromycin, 47% for oxytetracycline, and 47% for lincomycin. The current findings suggest that ceftiofur, erythromycin, lincomycin, and oxytetracycline should not be used in C. perfringens infection treatments in humans or animals in Saudi Arabia.

Rejuvenating the human gut microbiome

Industrial advances have caused significant loss of diversity in our gut microbiome, potentially increasing our susceptibility to many diseases. Recently, rewilding the human gut microbiome - that is, bringing it back to an ancestral or preindustrial state (e.g., by transplanting stool material from donors in nonindustrial societies) - has been hotly debated from medical, ethical, and evolutionary perspectives. Here we propose an alternative solution: rejuvenating the human gut microbiome by stool banking and autologous fecal microbiota transplantation, that is, collecting the hosts' stool samples at a younger age when they are at optimal health, and cryopreserving the samples in a stool bank for the hosts' own future use. In this article we discuss the motivation, applications, feasibility, and challenges of this solution.

Health care consequences of hospitalization with Clostrioides difficile infection: a propensity score matching study

Background

Clostridiodies difficile infection (CDI) has been characterized by the Center for Disease Control and Prevention (CDC) as an urgent public health threat and a major concern in hospital, outpatient and extended-care facilities worldwide.

Methods

A retrospective cohort study of patients aged ≥ 18 hospitalized with CDI in New York State (NYS) between January 1, 2014–December 31, 2016. Data were extracted from NY Statewide Planning and Research Cooperative (SPARCS) and propensity score matching was performed to achieve comparability of the CDI (exposure) and non-CDI (non-exposure) groups. Of the 3,714,486 hospitalizations, 28,874 incidence CDI cases were successfully matched to 28,874 non-exposures.

Results

The matched pairs comparison demonstrated that CDI cases were more likely to be readmitted to the hospital at 30 (28.26% vs. 19.46%), 60 (37.65% vs. 26.02%), 90 (42.93% vs. 30.43) and 120 days (46.47% vs. 33.74), had greater mortality rates at 7 (3.68% vs. 2.0%) and 180 days (20.54% vs. 11.96%), with significant increases in length of stay and total hospital charges (p < .001, respectively).

Conclusions

CDI is associated with a large burden on patients and health care systems, significantly increasing hospital utilization, costs and mortality.

Characterization of Healthcare-Associated and Community-Associated Clostridioides difficile Infections among Adults, Canada, 2015-2019

We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2019. The study encompassed 18,455 CDI cases, 13,735 (74.4%) HA and 4,720 (25.6%) CA. During 2015–2019, HA CDI rates decreased by 23.8%, whereas CA decreased by 18.8%. HA CDI was significantly associated with increased 30-day all-cause mortality as compared with CA CDI (p<0.01). Of 2,506 isolates analyzed, the most common ribotypes (RTs) were RT027, RT106, RT014, and RT020. RT027 was more often associated with CDI-attributable death than was non-RT027, regardless of acquisition type. Overall resistance C. difficile rates were similar for all drugs tested except moxifloxacin. Adult HA and CA CDI rates have declined, coinciding with changes in prevalence of RT027 and RT106. Infection prevention and control and continued national surveillance are integral to clarifying CDI epidemiology, investigation, and control.

Transitions of care in Clostridioides difficile infection: a need of the hour

Clostridioides difficile infection (CDI) is a complex disease that by virtue of both its initial virulence and proclivity toward recurrent episodes causes a high morbidity, mortality, and financial burden. This burden is felt by patients and their families as well as the U.S. healthcare system. Recurrent CDI episodes can occur in 25-65% of patients, with a cycle of multiple recurrences in a single patient contributing to the complexity of care. Patients with or suspected of having CDI will receive treatment and their care will be managed across multiple healthcare settings and will include many different levels of healthcare workers. The understanding of this infection is essential for all who are involved in the care of these patients. A well-structured and implemented Transition of Care process can ease the burden on the healthcare system, patients, and their families; reduce the cost of care; and improve patient outcomes. We review the development of Transitions of Care processes, resource guides, and their relevance to improving the management of CDI.

Assembly of the exosporium layer in Clostridioides difficile spores

Clostridioides difficile is a Gram-positive, spore-forming obligate anaerobe and a major threat to the healthcare system world-wide. Because of its strict anaerobic requirements, the infectious and transmissible morphotype is the dormant spore. During infection, C. difficile produces spores that can persist in the host and are responsible for disease recurrence and transmission, especially between hospitalized patients. Although the C. difficile spore surface mediates critical interactions with host surfaces, this outermost layer, known as the exosporium, is poorly conserved when compared to members of the Bacillus genus. Notably, the exosporium has been shown to be important for the persistence of C. difficile in the host. In this review, the ultrastructural properties, composition, and morphogenesis of the exosporium will be discussed.

How Does COVID-19 Pandemic Impact on Incidence of Clostridioides difficile Infection and Exacerbation of Its Gastrointestinal Symptoms?

Coronavirus disease 2019 (COVID-19) has rapidly spread all over the world with a very high rate of mortality. Different symptoms developed by COVID-19 infection and its impacts on various organs of the human body have highlighted the importance of both coinfections and superinfections with other pathogens. The gastrointestinal (GI) tract is vulnerable to infection with COVID-19 and can be exploited as an alternative transmission route and target for virus entry and pathogenesis. The GI manifestations of COVID-19 disease are associated with severe disease outcomes and death in all age groups, in particular, elderly patients. Empiric antibiotic treatments for microbial infections in hospitalized patients with COVID-19 in addition to experimental antiviral and immunomodulatory drugs may increase the risk of antibiotic-associated diarrhea (AAD) and Clostridioides difficile infection (CDI). Alterations of gut microbiota are associated with depletion of beneficial commensals and enrichment of opportunistic pathogens such as C. difficile. Hence, the main purpose of this review is to explain the likely risk factors contributing to higher incidence of CDI in patients with COVID-19. In addition to lung involvement, common symptoms observed in COVID-19 and CDI such as diarrhea, highlight the significance of bacterial infections in COVID-19 patients. In particular, hospitalized elderly patients who are receiving antibiotics might be more prone to CDI. Indeed, widespread use of broad-spectrum antibiotics such as clindamycin, cephalosporins, penicillin, and fluoroquinolones can affect the composition and function of the gut microbiota of patients with COVID-19, leading to reduced colonization resistance capacity against opportunistic pathogens such as C. difficile, and subsequently develop CDI. Moreover, patients with CDI possibly may have facilitated the persistence of SARS-CoV-2 viral particles in their feces for approximately one month, even though the nasopharyngeal test turned negative. This coinfection may increase the potential transmissibility of both SARS-CoV-2 and C. difficile by fecal materials. Also, CDI can complicate the outcome of COVID-19 patients, especially in the presence of comorbidities or for those patients with prior exposure to the healthcare setting. Finally, physicians should remain vigilant for possible SARS-CoV-2 and CDI coinfection during the ongoing COVID-19 pandemic and the excessive use of antimicrobials and biocides.

Risk Factors for Recurrence of Clostridioides difficile in Hospitalized Patients

BACKGROUND

Diarrhea and pseudomembranous colitis associated with Clostridioides difficile - a spore-forming anaerobic Gram-positive bacillus - is a major infection in hospitalized patients with a profound impact on clinical and economic outcomes. Recurrence (rCDI) is common and predisposes to further episodes with poor outcomes.

METHOD

We aimed to identify a wide range of risk factors for recurrence to guide stewardship initiatives. After ethical approval, we commenced collecting demographic and clinical data of patients older than 18 years with clinically and microbiologically confirmed C. difficile infection. Data were statistically analyzed using R software.

RESULTS

Of 204 patients included in the analysis, 36 (18%) suffered 90-day recurrence, rCDI was higher among females (23%) compared to males (13%), overall age median (IQR) was 66 (51-77), and for rCDI cases 81 (69-86) years. Among 26 variables analyzed to evaluate their association with rCDI, prior clindamycin exposure, concurrent use of aztreonam, patients >76 years, total hospital length of stay, and LOS before diagnosis ≤7 days, WBC ≤ 9.85 × 10³ at discharge were more likely to experience rCDI.

CONCLUSION

As identified in this analysis, patients with risk factors for rCDI could be candidates for close monitoring, a high index of suspicion, and risk mitigation interventions to avoid rCDI and improve clinical outcomes.

A prospective, observational study of fidaxomicin use for Clostridioides difficile infection in France

OBJECTIVE

To describe the characteristics, management and outcomes of hospitalised patients with Clostridioides difficile infection (CDI) treated with and without fidaxomicin.

METHODS

This prospective, multicentre, observational study (DAFNE) enrolled hospitalised patients with CDI, including 294 patients treated with fidaxomicin (outcomes recorded over a 3-month period) and 150 patients treated with other CDI therapies during three 1-month periods. The primary endpoint was baseline and CDI characteristics of fidaxomicin-treated patients.

RESULTS

At baseline, the fidaxomicin-treated population included immunocompromised patients (39.1%) and patients with severe (59.2%) and recurrent (36.4%) CDI. Fidaxomicin was associated with a high rate of clinical cure (92.2%) and low CDI recurrence (16.3% within 3 months). Clinical cure rates were ≥90% in patients aged ≥65 years, those receiving concomitant antibiotics and those with prior or severe CDI. There were 121/296 (40.9%) patients with adverse events (AEs), 5.4% with fidaxomicin-related AEs and 1.0% with serious fidaxomicin-related AEs. No fidaxomicin-related deaths were reported.

CONCLUSIONS

Fidaxomicin is an effective and well-tolerated CDI treatment in a real-world setting in France, which included patients at high risk of adverse outcomes.Trial registration: Description of the use of fidaxomicin in hospitalised patients with documented Clostridium difficile infection and the management of these patients (DAFNE), NCT02214771, www.ClinicalTrials.gov.

rUTI Resolution After FMT for Clostridioides difficile Infection: A Case Report

Clostridioides difficile infection (CDI) is the leading cause of nosocomial infectious diarrhea. Fecal microbiota transplantation (FMT) is a successful treatment for recurrent CDI (rCDI), and in some patients FMT has been associated with the resolution of recurrent urinary tract infections (rUTI). Recent evidence suggests that the origin of most bacterial infections in the urinary tract is the gut. Thus, the possibility of using FMT to displace pathogens commonly involved in rUTIs has major therapeutic implications. We report the case of a 93-year-old female patient with a rCDI and rUTI that underwent FMT and reported a complete clinical resolution of CDI; unexpectedly, no new symptomatic UTI episodes were diagnosed post-FMT. We characterized the gut microbiota of the stool donor and of the patient before and after the procedure. Our patient presented a dysbiosis with clear predominance of Enterobacteriaceae (74%) before FMT, which was significantly reduced to 0.07% after FMT. These findings were maintained for almost a year. We also observed an increase in microbial diversity indices compared with the pre-FMT sample reaching diversity values comparable to the donor stool samples. We reasoned that the disappearance of UTIs in our patient resulted from the reduction of Enterobacteriaceae in the gut microbiota. Our findings support previous evidence suggesting the potential of FMT for rUTI, particularly in cases due to multi-drug resistant pathogens where conventional antibiotic treatment is not an option.

Characterization of an Endolysin Targeting Clostridioides difficile That Affects Spore Outgrowth

Clostridioides difficile is a spore-forming enteric pathogen causing life-threatening diarrhoea and colitis. Microbial disruption caused by antibiotics has been linked with susceptibility to, and transmission and relapse of, C. difficile infection. Therefore, there is an urgent need for novel therapeutics that are effective in preventing C. difficile growth, spore germination, and outgrowth. In recent years bacteriophage-derived endolysins and their derivatives show promise as a novel class of antibacterial agents. In this study, we recombinantly expressed and characterized a cell wall hydrolase (CWH) lysin from C. difficile phage, phiMMP01. The full-length CWH displayed lytic activity against selected C. difficile strains. However, removing the N-terminal cell wall binding domain, creating CWH_351—656, resulted in increased and/or an expanded lytic spectrum of activity. C. difficile specificity was retained versus commensal clostridia and other bacterial species. As expected, the putative cell wall binding domain, CWH_1—350, was completely inactive. We also observe the effect of CWH_351—656 on preventing C. difficile spore outgrowth. Our results suggest that CWH_351—656 has therapeutic potential as an antimicrobial agent against C. difficile infection.

Entry of spores into intestinal epithelial cells contributes to recurrence of Clostridioides difficile infection

Clostridioides difficile spores produced during infection are important for the recurrence of the disease. Here, we show that C. difficile spores gain entry into the intestinal mucosa via pathways dependent on host fibronectin-α5β1 and vitronectin-αvβ1. The exosporium protein BclA3, on the spore surface, is required for both entry pathways. Deletion of the bclA3 gene in C. difficile, or pharmacological inhibition of endocytosis using nystatin, leads to reduced entry into the intestinal mucosa and reduced recurrence of the disease in a mouse model. Our findings indicate that C. difficile spore entry into the intestinal barrier can contribute to spore persistence and infection recurrence, and suggest potential avenues for new therapies.

Safety and Efficacy of Fidaxomicin and Vancomycin in Children and Adolescents with Clostridioides (Clostridium) difficile Infection: A Phase 3, Multicenter, Randomized, Single-blind Clinical Trial (SUNSHINE)

BACKGROUND

Fidaxomicin, a narrow-spectrum antibiotic approved for Clostridioides (Clostridium) difficile infection (CDI) in adults, is associated with lower rates of recurrence than vancomycin; however, pediatric data are limited. This multicenter, investigator-blind, phase 3, parallel-group trial assessed the safety and efficacy of fidaxomicin in children.

METHODS

Patients aged <18 years with confirmed CDI were randomized 2:1 to 10 days of treatment with fidaxomicin (suspension or tablets, twice daily) or vancomycin (suspension or tablets, 4 times daily). Safety assessments included treatment-emergent adverse events. The primary efficacy end point was confirmed clinical response (CCR), 2 days after the end of treatment (EOT). Secondary end points included global cure (GC; CCR without CDI recurrence) 30 days after EOT (end of study; EOS). Plasma and stool concentrations of fidaxomicin and its active metabolite OP-1118 were measured.

RESULTS

Of 148 patients randomized, 142 were treated (30 <2 years old). The proportion of participants with treatment-emergent adverse events was similar with fidaxomicin (73.5%) and vancomycin (75.0%). Of 3 deaths in the fidaxomicin arm during the study, none were CDI or treatment related. The rate of CCR at 2 days after EOT was 77.6% (76 of 98 patients) with fidaxomicin and 70.5% (31 of 44) with vancomycin, whereas the rate of GC at EOS was significantly higher in participants receiving fidaxomicin (68.4% vs 50.0%; adjusted treatment difference, 18.8%; 95% confidence interval, 1.5%-35.3%). Systemic absorption of fidaxomicin and OP-1118 was minimal, and stool concentrations were high.

CONCLUSIONS

Compared with vancomycin, fidaxomicin was well tolerated and demonstrated significantly higher rates of GC in children and adolescents with CDI.

CLINICAL TRIALS REGISTRATION

NCT02218372.

Bacteriophage endolysins as a potential weapon to combat Clostridioides difficile infection

Clostridioides difficile is the leading cause of health-care-associated infection throughout the developed world and contributes significantly to patient morbidity and mortality. Typically, antibiotics are used for the primary treatment of C. difficile infections (CDIs), but they are not universally effective for all ribotypes and can result in antibiotic resistance and recurrent infection, while also disrupting the microbiota. Novel targeted therapeutics are urgently needed to combat CDI. Bacteriophage-derived endolysins are required to disrupt the bacterial cell wall of their target bacteria and are possible alternatives to antibiotics. These lytic proteins could potentially replace or augment antibiotics in CDI treatment. We discuss candidate therapeutic lysins derived from phages/prophages of C. difficile and their potential as antimicrobials against CDI. Additionally, we review the antibacterial potential of some recently identified homologues of C. difficile endolysins. Finally, the challenges of endolysins are considered with respect to the development of novel lysin-based therapies.

Risk of complications and mortality following recurrent and non-recurrent Clostridioides difficile infection: a retrospective observational database study in England

BACKGROUND

Clostridioides difficile infection (CDI) increases the risk of complications and mortality. We assessed the magnitude of these outcomes in a large cohort of English patients with initial and recurrent CDI.

AIM

To compare the risk of complications and all-cause mortality, within 12 months, among hospitalized patients ≥18 years old with hospital-associated- (HA-) CDI and recurrent CDI.

METHODS

Patients with HA-CDI during 2002-2013 were identified using inpatient hospital data linked to primary care and death data. Each HA-CDI case was frequency matched to two hospitalized patients without CDI on age group, sex, calendar year of admission, admission method and number of hospital care episodes. A second CDI episode starting on days 13-56 was defined as recurrence. Risks of mortality and complications at 12 months were analysed using Cox proportional hazard models.

FINDINGS

We included 6862 patients with HA-CDI and 13,724 without CDI. Median age was 81.0 years (IQR 71.0-87.0). Patients with HA-CDI had more comorbidities than those without CDI, and significantly higher risks of mortality (adjusted hazard ratio (95% confidence interval) 1.77 (1.67-1.87)) and complications (1.66 (1.46-1.88)) within 12 months from hospital admission. Of those with HA-CDI, 1140 (16.6%) experienced CDI recurrence. Patients with recurrent versus non-recurrent CDI also had significantly increased risk of mortality (1.32 (1.20-1.45)) and complications (1.37 (1.01-1.84)) in the 12 months from the initial CDI.

CONCLUSIONS

HA-CDI (versus no CDI) and recurrent CDI are both associated with significantly higher risks of complications or death within 12 months of the initial CDI episode.

Cost-effectiveness analysis of a fecal microbiota transplant center for treating recurrent C.difficile infection

OBJECTIVE

We assessed the cost-effectiveness of establishing a fecal microbial transplant (FMT) unit in Canada for the treatment of recurrent CDI.

DESIGN

We performed a cost-effectiveness analysis to determine the number of patients with recurrent CDI needed to treat (NNT) annually to make establishing a FMT unit cost-effective. We compared treating patients for their second recurrence of CDI with FMT in a jurisdiction with a FMT unit, compared to being treated with antibiotics; then sent to a medical center with FMT available for the third recurrence. We used a willingness to pay threshold of $50,000 per quality-adjusted-life-year gained.

RESULTS

The minimum annual NNT was 15 for FMT via colonoscopy, 17 for FMT via capsule, and 44 for FMT via enema compared with vancomycin, and 16, 18, and 47 compared with fidaxomicin, respectively. A medical center's minimum catchment area when establishing a FMT unit would have to be 56,849 if using FMT via colonoscopy, or 64,429 if using capsules.

CONCLUSION

We report the minimum number of patients requiring treatment annually with FMT to achieve cost-effectiveness, when including start-up and ongoing costs. FMT is cost-effective in Canada in populations with a sufficient number of eligible patients, ranging from 15 to 47 depending on the FMT modality used. This is crucial for medical jurisdictions making decisions about establishing a FMT unit for the treatment of recurrent CDI. The cost-effectiveness can be generalized in other countries.

Clinical impact of a Clostridioides (Clostridium) difficile bedside infectious disease stewardship intervention

Objectives

To evaluate the clinical impact of a bedside visit to patients with a positive Clostridioides difficile test on the antimicrobial stewardship of C. difficile infection (CDI) and non-C. difficile infections.

Methods

All patients ≥18 years old with positive CDI laboratory tests hospitalized between January 2017 and August 2017 received an immediate bedside intervention that consisted mainly of checking protective measures and providing recommendations on infection control and the management of CDI and other infections.

Results

A total of 214 patients were evaluated. The infectious disease (ID) physician was the first to establish protective measures in 25.2% of the cases. In 22/29 (75.9%) cases, physicians in charge accepted ID consultant recommendations to stop CDI treatment in asymptomatic patients. Unnecessary non-CDI antibiotics were discontinued in 19.1% of the cases. ID recommendations were not accepted by physicians in charge in only 12.6% of the cases.

Conclusions

A bedside rapid intervention for patients with a CDI-positive faecal sample was effective in avoiding overdiagnosis and unnecessary antibiotic treatment, optimizing anti-CDI drugs, increasing compliance with infection control measures and providing educational advice.

Fidaxomicin for the treatment of Clostridioides difficile in children

Fidaxomicin is an oral narrow-spectrum novel 18-membered macrocyclic antibiotic that was initially approved in 2011 by the US FDA for the treatment of Clostridioides difficile infections (CDI) in adults. In February 2020, the FDA approved fidaxomicin for the treatment of CDI in children age >6 months. In adults, fidaxomicin is as efficacious as vancomycin in treating CDI and reduces the risk of recurrent CDI. An investigator-blinded, randomized, multicenter, multinational clinical trial comparing the efficacy and safety of fidaxomicin with vancomycin in children was recently published confirming similar findings as previously reported in adults. Fidaxomicin is the first FDA-approved treatment for CDI in children and offers a promising option for reducing recurrent CDI in this population.

Cost burden of Clostridioides difficile infection to the health service: A retrospective cohort study in Scotland

BACKGROUND

Clostridioides difficile infection (CDI) is associated with high healthcare demands and related costs.

AIM

To evaluate the healthcare and economic burden of CDI in hospitalized patients with community- (HOCA-CDI) or hospital-associated CDI (HOHA-CDI) in the National Health Service in Scotland.

METHODS

A retrospective cohort study was conducted, examining data between August 2010 and July 2013 from four patient-level Scottish datasets, linked to death data. Data examined included prior antimicrobial prescriptions in the community, hospitalizations, length of stay and mortality. Each CDI case was matched to three hospital-based controls on the basis of age, gender, hospital and date of admission. Descriptive economic evaluations were based on bed-day costs for different types of wards.

FINDINGS

Overall, 3304 CDI cases were included in the study. CDI was associated with additional median lengths of stay of 7.2 days for HOCA-CDI and 12.0 days for HOHA-CDI compared with their respective, matched controls. The 30-day mortality rate was 6.8% for HOCA-CDI and 12.4% for HOHA-CDI. Overall, recurrence within 90 days of the first CDI episode occurred in 373/2740 (13.6%) survivors. The median additional expenditure for each initial CDI case compared with matched controls was £1713. In the 6 months after the index hospitalization, the cost associated with a CDI case was £5126 higher than for controls.

CONCLUSION

Using routinely collected national data, we demonstrated the substantial burden of CDI on healthcare services, including lengthy hospital stays and readmissions, which increased the costs of managing patients with CDI compared with matched controls.

The Impact of Clostridium Difficile Infections on In-Hospital Outcomes of Venous Thromboembolism (Deep Vein Thrombosis or Pulmonary Embolism) Hospitalizations

Background

Clostridium difficile infection (CDI) is associated with high mortality. Studies have shown an increased rate of venous thromboembolism (VTE) in patients with CDI. However, literature regarding the impact of CDI on outcomes of VTE-related hospitalizations is scarce. Our study aimed to assess the impact of CDI on in-hospital outcomes among VTE hospitalizations.

Methods

The 2016 National Inpatient Sample (NIS) was used to identify all adult hospitalizations in the United States with a primary discharge diagnosis of acute VTE. Hospitalizations with deep vein thrombosis (DVT) or pulmonary embolism (PE) were included under VTE. The sample was stratified based on the presence or absence of active CDI. Chi-square test and weighted Student’s t-test were used to analyze categorical and continuous variables, respectively. The adjusted odds ratio (OR) for clinical outcomes were calculated using multivariate logistic regression analysis. Subgroup analyses for DVT and PE hospitalizations were performed. All analyses were completed in SAS (SAS Institute Inc., Cary, NC), and a p-value of <0.05 was considered statistically significant.

Results

We identified 382,585 weighted hospitalizations for VTE. Among them, 0.8% had concomitant CDI. The presence of CDI was associated with a statistically significant increase in in-hospital mortality (6% vs. 3%), hospitalization cost ($147,356.5 vs. $55,193), and length of stay (13.7 vs. 5.4 days). There were more incidents of bleeding and acute respiratory failure requiring prolonged ventilation in patients with CDI. The odds of stroke were significantly higher in patients with CDI and DVT.

Conclusion

CDI independently increased in-hospital mortality in VTE. Preventing CDI in the VTE population may mitigate complications, improve in-hospital outcomes, and reduce treatment costs.

Diagnosing Clostridioides difficile infections with molecular diagnostics: multicenter evaluation of revogene C. difficile assay

Clostridioides difficile infections are a significant threat to our healthcare system, and rapid and accurate diagnostics are crucial to implement the necessary infection prevention and control measurements. Nucleic acid amplification tests are such reliable diagnostic tools for the detection of toxigenic Clostridioides difficile strains directly from stool specimens. In this multicenter evaluation, we determined the performance of the revogene C. difficile assay. The analysis was conducted on prospective stool specimens collected from six different sites in Europe. The performance of the revogene C. difficile assay was compared to the different routine diagnostic methods and, for a subset of the specimens, against toxigenic culture. In total, 2621 valid stool specimens were tested, and the revogene C. difficile assay displayed a sensitivity/specificity of 97.1% [93.3-99.0] and 98.9% [98.5-99.3] for identification of Clostridioides difficile infection. Discrepancy analysis using additional methods improved this performance to 98.8% [95.8-99.9] and 99.6% [99.2-99.8], respectively. In comparison to toxigenic culture, the revogene C. difficile assay displayed a sensitivity/specificity of 93.0% [86.1-97.1] and 99.5% [98.7-99.9], respectively. These results indicate that the revogene C. difficile assay is a robust and reliable aid in the diagnosis of Clostridioides difficile infections.

Recommendations for the diagnosis and treatment of Clostridioides difficile infection: An official clinical practice guideline of the Spanish Society of Chemotherapy (SEQ), Spanish Society of Internal Medicine (SEMI) and the working group of Postoperative Infection of the Spanish Society of Anesthesia and Reanimation (SEDAR)

This document gathers the opinion of a multidisciplinary forum of experts on different aspects of the diagnosis and treatment of Clostridioides difficile infection (CDI) in Spain. It has been structured around a series of questions that the attendees considered relevant and in which a consensus opinion was reached. The main messages were as follows: CDI should be suspected in patients older than 2 years of age in the presence of diarrhea, paralytic ileus and unexplained leukocytosis, even in the absence of classical risk factors. With a few exceptions, a single stool sample is sufficient for diagnosis, which can be sent to the laboratory with or without transportation media for enteropathogenic bacteria. In the absence of diarrhoea, rectal swabs may be valid. The microbiology laboratory should include C. difficile among the pathogens routinely searched in patients with diarrhoea. Laboratory tests in different order and sequence schemes include GDH detection, presence of toxins, molecular tests and toxigenic culture. Immediate determination of sensitivity to drugs such as vancomycin, metronidazole or fidaxomycin is not required. The evolution of toxin persistence is not a suitable test for follow up. Laboratory diagnosis of CDI should be rapid and results reported and interpreted to clinicians immediately. In addition to the basic support of all diarrheic episodes, CDI treatment requires the suppression of antiperistaltic agents, proton pump inhibitors and antibiotics, where possible. Oral vancomycin and fidaxomycin are the antibacterials of choice in treatment, intravenous metronidazole being restricted for patients in whom the presence of the above drugs in the intestinal lumen cannot be assured. Fecal material transplantation is the treatment of choice for patients with multiple recurrences but uncertainties persist regarding its standardization and safety. Bezlotoxumab is a monoclonal antibody to C. difficile toxin B that should be administered to patients at high risk of recurrence. Surgery is becoming less and less necessary and prevention with vaccines is under research. Probiotics have so far not been shown to be therapeutically or preventively effective. The therapeutic strategy should be based, rather than on the number of episodes, on the severity of the episodes and on their potential to recur. Some data point to the efficacy of oral vancomycin prophylaxis in patients who reccur CDI when systemic antibiotics are required again.

Effects of co-infection on the clinical outcomes of Clostridium difficile infection

Background

Clostridium difficile (C. difficile) is a spore-forming, Gram-positive rod that is known to be associated with antibiotic use. It is one of the leading causes of nosocomial diarrhea in the industrialized world and therefore warrants further study of its nature. It isn't clear if co-infection by other organisms can affect the outcome of C. difficile infection (CDI).

Methods

A single center retrospective study was done and it used inclusion criteria of 18 years of age and being tested positive for CDI on FilmArray® multiplex gastro-intestinal (GI) panel. Exclusion criteria were a GI panel performed on an outpatient basis, recurrent CDI, and the presence of end-stage renal disease, cirrhosis, or a non-GI infection. The stool sample for all patients were collected within 48 h of presentation to the hospital. There were 235 of 2576 GI panels selected for a retrospective chart review based on the above criteria. Among these 235 patients, 38 had a co-infection (CDI+ another GI infection = group A or cases) and the rest had only CDI (group B or controls). Group A was compared with group B for CDI severity, its response to treatment, recurrence, and length of the hospital stay, using 0.05 as the alpha criterion.

Results

Most patients with CDI were female and above the age of 60 years. Co infection did not increase the severity of CDI based both on the American College of Gastroenterology criteria (p 0.16) as well as Infectious Disease Society of America criteria (p 0.77). Co infection group also didn't have significantly different CDI related treatment failure rate (p 0.23), or CDI recurrence rate (p 0.49). Co-infection was also not associated with lengthier hospital stay (p 0.41).

Conclusion

Our study suggests that co-infection doesn't affect the severity of CDI or can cause treatment failures. Additionally, there was no significant increase in hospital stay, or increase in CDI recurrence associated with co-infection. Therefore, if CDI is the leading clinical diagnosis and a patient is tested positive for co-infection in addition to CDI on FilmArray® multiplex GI panel, this co-infection shouldn't change the management for CDI. Limitations of this study (including retrospective nature of the study, small sample size, single site study, not including all microbiome and non-inclusion of race) should also be taken into account, while considering the applicability of the results of this study.

In vitro Production and Immunogenicity of a Clostridium Difficile Spore-Specific BclA3 Glycopeptide Conjugate Vaccine

Abstract: The BclA3 glycoprotein is a major component of the exosporangial layer of Clostridium difficile spores and in this study we demonstrate that this glycoprotein is a major spore surface associated antigen. Here, we confirm the role of SgtA glycosyltransferase (SgtA GT) in BclA3 glycosylation and recapitulate this process by expressing and purifying SgtA GT fused to MalE, the maltose binding protein from Escherichia coli. In vitro assays using the recombinant enzyme and BclA3 synthetic peptides demonstrated that SgtA GT was responsible for the addition of β-O-linked GlcNAc to threonine residues of each synthetic peptide. These peptide sequences were selected from the central, collagen repeat region of the BclA3 protein. Following optimization of SgtA GT activity, we generated sufficient glycopeptide (10 mg) to allow conjugation to KLH (keyhole limpet hemocyanin) protein. Glycosylated and unglycosylated versions of these conjugates were then used as antigens to immunize rabbits and mice. Immune responses to each of the conjugates were examined by Enzyme Linked Immunosorbent Assay ELISA. Additionally, the BclA3 conjugated peptide and glycopeptide were used as antigens in an ELISA assay with serum raised against formalin-killed spores. Only the glycopeptide was recognized by anti-spore polyclonal immune serum demonstrating that the glycan moiety is a predominant spore-associated surface antigen. To determine whether antibodies to these peptides could modify persistence of spores within the gut, animals immunized intranasally with either the KLH-glycopeptide or KLH-peptide conjugate in the presence of cholera toxin, were challenged with R20291 spores. Although specific antibodies were raised to both antigens, immunization did not provide any protection against acute or recurrent disease.

Role of Post-Acute Care in Readmissions for Preexisting Healthcare-Associated Infections

OBJECTIVES

Although preventable, healthcare-associated infections (HAIs) are commonly observed in post-acute care settings for at-risk older adults and are a leading cause of hospital readmissions. However, whether HAIs resulting in avoidable readmissions for preexisting HAIs (the same HAI as at the index admission) are more common for patients discharged to post-acute care as opposed to home is unknown. We examined the risk of preexisting HAI readmissions according to patient discharge disposition and comorbidity level.

DESIGN

We used 2013-2014 national hospital discharge data to estimate the likelihood of readmissions for preexisting HAIs according to patients' discharge disposition and whether the likelihood varies according to patient comorbidity level, across four common types of HAIs (not including respiratory infections).

PARTICIPANTS

A total of 702 304 hospital discharges for Medicare beneficiaries 65 years or older.

MEASUREMENTS

Our outcome was a 30-day preexisting, or "linked," HAI readmission (readmission involving the same HAI diagnosis as at the index admission). Patient discharge disposition was skilled nursing facility (SNF), home health care, and home care without home health care ("home").

RESULTS

Of 702 304 index admissions involving HAI treatment, 353 073 (50%) were discharged to a SNF, 179 490 (26%) to home health care, and 169 872 (24%) to home. Overall, 17 523 (2.5%) of preexisting HAIs resulted in linked HAI readmissions, which were more common for Clostridioides difficile infections (4.0%) and urinary tract infections (2.4%) than surgical site infections (1.1%; P < .001). Being discharged to a SNF compared to home or to home health care was associated with a 1.15 percentage point (95% confidence interval = -1.29 to -1.00), or 38%, lower risk of a linked HAI readmission. This risk difference was observed to increase with greater patient comorbidity.

CONCLUSIONS

SNF discharges were associated with fewer avoidable readmissions for preexisting HAIs compared with home discharges. Further research to identify modifiable mechanisms that improve posthospital infection care at home is needed. J Am Geriatr Soc 68:370-378, 2020.

Clostridium difficile colitis in patients undergoing surgery for hip fractures: an analysis of 17,474 patients

BACKGROUND

We compiled evidence from a large national surgical database to identify the incidence, risk factors and postoperative impact of Clostridium difficile infection (CDI) in patients undergoing hip fracture repair.

METHODS

We identified 17,474 patients who underwent hip fracture repairs in 2015 using the ACS-NSQIP database. Interventions studied were open reduction/Internal fixation, total hip arthroplasty or hemiarthroplasty being performed for traumatic hip fractures. Outcomes studied were incidence, preoperative and postoperative risk factors for occurrence of CDI were studied using descriptive and statistical analysis.

RESULTS

A total of 92 patients (0.53%) developed CDI within 30 days of the operation. Following adjustment using multi-variate logistic regression, preoperative and hospital-associated factors associated with development of CDI were smoking (OR 1.75 [95% CI 1.03-2.99]), hypertension (OR 1.70 [95% CI 1.01-2.85]), hyponatraemia (OR 1.65 [95% CI 1.04-2.63]), prior systemic inflammatory response syndrome (SIRS) (OR 2.18 [95% CI 1.32-3.59]) and a length of stay >7 days (OR 1.98 [95% CI 1.11-3.53]. Postoperative factors associated with occurrence of CDI were occurrence of a deep surgical site infection (SSI) (OR 5.89 [95% CI 1.31-26.6]), a stay in the hospital >30 days (OR 6.56 [95% CI 2.56-16.9]) and unplanned reoperations (OR 2.78 [95% CI 1.29-5.99]).

CONCLUSION

As we move toward an era of bundled-payment models, identification of risk factors associated with the occurrence of postoperative complications, such as CDI, will help curb excess healthcare utilisation and costs associated with the management of this complication.

Microbiological Characterization and Clinical Outcomes After Extended-Pulsed Fidaxomicin Treatment for Clostridioides difficile Infection in the EXTEND Study

Background

Clostridioides (Clostridium) difficile infection (CDI) is diagnosed using clinical signs and symptoms plus positive laboratory tests. Recurrence of CDI after treatment is common, and coinfection with other enteric pathogens may influence clinical outcomes.

Methods

We aimed to assess rates of C difficile positivity, by enzyme-linked immunosorbent assay (ELISA) toxin A/B and BioFire FilmArray, and the effect of enteric coinfection on clinical outcomes, using samples from the EXTEND study of extended-pulsed fidaxomicin (EPFX) versus standard vancomycin.

Results

All 356 randomized and treated patients tested positive for C difficile toxin A/B by local tests; a majority (225 of 356, 63.2%) also tested positive by both ELISA and BioFire. Most stool samples taken at screening tested positive for C difficile only using BioFire (EPFX: 112 of 165, 69.7%; vancomycin: 118 of 162, 72.8%). Of the 5 patients who failed treatment and had stool samples available, all (1) had tested negative for C difficile by BioFire at screening and (2) were negative by ELISA at time of treatment failure. When analyzed by BioFire results at screening, rates of sustained clinical cure at 30 days after end of treatment were numerically higher with EPFX than with vancomycin for almost all patients, except for those who tested negative for C difficile but positive for another pathogen. However, these outcome differences by presence of coinfection did not reach statistical significance. Whole-genome sequencing analysis determined that 20 of 26 paired samples from patients with recurrence were reinfections with the same C difficile strain.

Conclusions

Testing for presence of copathogens in clinical trials of antibiotics could help to explain clinical failures.

Clostridium difficile Colitis Following Revision Total Knee Arthroplasty: Incidence and Risk Factors

BACKGROUND

Clostridium difficile-associated diarrhea (CDAD) is associated with adverse events and financial liability. As institutions continue to adopt CDAD rates as a quality control metric, it is important to identify patients at risk before surgery, including revision total knee arthroplasty (rTKA). This study was conducted to (1) determine the incidence of CDAD within 30 days of rTKA and (2) identify perioperative risk factors for CDAD following rTKA.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program was queried to identify 6023 rTKA procedures from 2015-2016. Preoperative and perioperative variables, including patient demographics, lab values, comorbidities, operative time, procedure type, presence of postoperative infections, and rates of CDAD were collected. Chi-square and Fisher's exact tests were used to detect differences between categorical variables, and t-tests were used to compare continuous variables. A stepwise logistic regression model was used to identify the risk factors for CDAD.

RESULTS

The rate of CDAD within 30 days of rTKA was found to be 0.4% (24/6024). The CDAD rate following aseptic revision was 0.2% (12/4893), while the incidence of CDAD after septic revision was 1.1% (12/1130). Preoperative functional dependence (odds ratio [OR] = 5.14; P = .002), septic revision (OR = 2.77; P = .026), and cancer (OR = 14.26; P = .016) were statistically significant independent risk factors for CDAD after rTKA.

CONCLUSION

The incidence of CDAD after rTKA is approximately 0.4% in the United States. Independent risk factors for CDAD include septic revision, preoperative functional dependence, and cancer. Prevention of CDAD in these higher risk patients must be considered before surgery and antibiotic selection for other infections should be managed judiciously.

Cost-effectiveness of Bezlotoxumab Compared With Placebo for the Prevention of Recurrent Clostridium difficile Infection

Background

Clostridium difficile infection (CDI) is the most commonly recognized cause of recurrent diarrhea. Bezlotoxumab, administered concurrently with antibiotics directed against C. difficile (standard of care [SoC]), has been shown to reduce the recurrence of CDI, compared with SoC alone. This study aimed to assess the cost-effectiveness of bezlotoxumab administered concurrently with SoC, compared with SoC alone, in subgroups of patients at risk of recurrence of CDI.

Methods

A computer-based Markov health state transition model was designed to track the natural history of patients infected with CDI. A cohort of patients entered the model with either a mild/moderate or severe CDI episode, and were treated with SoC antibiotics together with either bezlotoxumab or placebo. The cohort was followed over a lifetime horizon, and costs and utilities for the various health states were used to estimate incremental cost-effectiveness ratios (ICERs). Both deterministic and probabilistic sensitivity analyses were used to test the robustness of the results.

Results

The cost-effectiveness model showed that, compared with placebo, bezlotoxumab was associated with 0.12 quality-adjusted life-years (QALYs) gained and was cost-effective in preventing CDI recurrences in the entire trial population, with an ICER of $19824/QALY gained. Compared with placebo, bezlotoxumab was also cost-effective in the subgroups of patients aged ≥65 years (ICER of $15298/QALY), immunocompromised patients (ICER of $12597/QALY), and patients with severe CDI (ICER of $21430/QALY).

Conclusions

Model-based results demonstrated that bezlotoxumab was cost-effective in the prevention of recurrent CDI compared with placebo, among patients receiving SoC antibiotics for treatment of CDI.

Fidaxomicin compared with vancomycin and metronidazole for the treatment of Clostridioides (Clostridium) difficile infection: A network meta-analysis

We conducted a systematic review of the literature and network meta-analysis (NMA) to compare the relative effectiveness of antibiotic treatments for Clostridioides (Clostridium) difficile infection (CDI) including vancomycin (VCM), metronidazole (MTZ) and fidaxomicin (FDX). Eligible studies were randomised controlled trials (RCTs) including adults with any severity of CDI that was treated with VCM, MTZ or FDX. The NMA was performed using a Bayesian framework, using a fixed-effects model. The searches identified seven publications for inclusion, which provided five RCTs for VCM versus MTZ, and three RCTs for FDX versus VCM. The NMA showed that for clinical cure rate, there was no difference for FDX versus VCM, and there was a significant difference in favour of FDX versus MTZ (odds ratio [OR]: 1.77; 95% credible interval [CrI] 1.11, 2.83]). For recurrence rate, there was a significant difference in favour of FDX versus both VCM (OR: 0.50; 95% CrI: 0.37, 0.68) and MTZ (OR: 0.44; 95% CrI: 0.27, 0.72). For sustained cure (clinical cure without recurrence), there was a significant difference in favour of FDX versus VCM (OR: 1.61; 95% CrI: 1.27, 2.05) and MTZ (OR: 2.39; 95% CrI: 1.65, 3.47). These findings suggest that FDX and VCM are effective first-line treatments for mild or moderate CDI, whereas MTZ is not, and FDX may be more effective at preventing CDI recurrence than VCM.

Multiplex polymerase chain reaction detection of enteropathogens in sewage in Norway

The primary objective of this small-scale study was to investigate the occurrence of enteropathogens in sewage (municipal wastewater) in Norway using the commercially available FilmArray^® multiplex polymerase chain reaction (PCR) system with the gastrointestinal (GI) panel. Our findings indicate that DNA/RNA of several enteropathogens are present simultaneously in Norwegian wastewater systems. The spectre was broad even in smaller communities. With some exceptions, occurrence corresponded more or less to the reported cases of infectious human gastrointestinal disease in the same geographical regions. The effects of different sewage purification techniques were assessed on a limited number of samples indicating that neither chemical nor biological treatment was sufficiently effective to reduce gene material from the pathogens to undetectable levels. Further studies are required to assess the performance and suitability FilmArray^® multiplex PCR when used on collective sewage samples in outbreak situations. Additionally, screening sewage samples using multiplex-PCR could be valuable in order to detect new and emerging pathogens and for preliminary analysis of samples before proceeding to more work demanding confirmatory techniques.