Global burden of Clostridium difficile infections: a systematic review and meta-analysis

Proton pump inhibitors and the risk of Clostridioides difficile infection: A systematic review and dose-response meta-analysis

BACKGROUND

Clostridioides difficile is a leading cause of healthcare-associated infections globally with proton pump inhibitor (PPI) use as important modifiable risk factor. This study aimed to systematically synthesise global evidence on the dose-response relationship of PPI usage and the Clostridioides difficile infection (CDI) risk and to identify potential safe thresholds of PPI usage regarding CDI.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library were searched for longitudinal studies regarding PPIs and CDI. Aggregated data were included in two separate two-stage random-effects dose-response meta-analyses regarding Defined Daily Dose (DDD) and PPI therapy duration. Pooled adjusted relative risks (RRs) with 95% confidence intervals compared to non-users of PPIs were estimated.

FINDINGS

Overall, 15 observational cohort and case-control studies were included with 7 studies (n=483,821) in the meta-analysis per DDD and 7 studies (n=516,441) per PPI therapy duration. The risk of bias was modest. Pooled dose-response estimates suggest linear trends with a RR of 1.05 (95% CI 0.89,1.23) per 10 mg DDD and of 1.02 (95% CI 1.00,1.05) per day of PPI therapy. Substantial residual heterogeneity was detected in both analyses (I2=91.4% per DDD and I2=99.4% per therapy duration), but inferring potential sources was limited.

INTERPRETATION

Our results indicate a possible increase in the risk of CDI with increasing dose and duration of PPI therapy. Underlying mechanisms and dosage thresholds for a clinically relevant risk increase remain unclear.

Global Practice Variation in the Management of Clostridioides difficile Infections: An International Cross-Sectional Survey of Clinicians

Background

Clostridioides difficile infections (CDIs) are associated with significant morbidity, mortality, and economic burden globally. International guidelines conflict on various aspects of management, so we conducted a clinician survey to evaluate global practice variability on CDI diagnosis, treatment, and prophylaxis to inform future clinical trials.

Methods

An anonymous online survey through REDCap was distributed through multiple channels. Attending physicians, infectious disease pharmacists, and fellows in infectious diseases or medical microbiology who had managed ≥3 cases of CDI in the preceding year were eligible. Responses were compared across continents by chi-square test.

Results

Three hundred fifty-nine survey responses were collected from 31 countries and 6 continents (North America 80.5%, Europe 11.7%, other continents 7.8%). A 2-step CDI diagnostic algorithm was used by 75.8% of respondents with heterogeneity in assay type. Similarly, there was significant variability in first-line agents for the treatment of first episodes and first recurrences of uncomplicated CDI and a lack of consensus on treatments for fulminant CDI. Secondary CDI prophylaxis during antibiotic re-exposure was most commonly used in North America (84.1%), followed by other continents (50.0%) and Europe (31.0%; P < .001). Oral vancomycin was the most frequently used agent (96.3%), with significant variability in the dose (125-500 mg daily) and duration (1-28 days; P < .01).

Conclusions

Substantial global variability exists with respect to CDI diagnosis, treatment, and secondary prophylaxis, likely due to divergent guidelines and a paucity of robust evidence. These findings highlight critical knowledge gaps and areas of clinical equipoise and underscore the need for further randomized controlled trials to establish harmonized international best practices for CDI.

Global, regional, and national burdens of Clostridioides difficile infection over recent decades: a trend analysis informed by the Global Burden of Disease Study

This study aimed to assess the global burden of Clostridioides difficile infection (CDI) from 1990 to 2019, focusing on disability-adjusted life years (DALYs) rates, mortality, and trends. Data were extracted from the Global Burden of Disease Study 2019 and analyzed globally, regionally, and nationally by age, sex, region, and socio-demographic index (SDI). Measures included age-standardized DALYs rate (ASDR), mortality rate (ASMR), and average annual percentage changes (AAPCs). Decomposition analysis and Bayesian age-period-cohort model were used to evaluate factors affecting CDI trends and predict future progress, respectively. Globally, the overall ASDR and ASMR of CDI showed an increasing trend (AAPCASDR = 1.39, 95% CI: 1.23-1.55; AAPCASMR = 2.79, 95% CI: 2.66-2.93). High SDI countries showed the highest ASDR (18.86, 95% CI: 17.46-20.24) and ASMR (0.99, 95% CI: 0.87- 1.11), with the fastest growth rate (AAPCASDR = 2.84, 95% CI: 2.64-3.04; AAPCASMR = 4.26, 95% CI: 3.98-4.55). Conversely, the low SDI regions exhibit negative growth; however, some low-middle SDI regions, such as South Africa, experienced a heavy disease burden. While most of the disease burden occurs in people over 70 years of age, the burden of children under 5 years of age should also be considered. Moreover, the increased burden on high SDI regions is primarily driven by epidemiological changes. CDI burden has risen globally, particularly in high SDI regions. Moreover, clinicians should take care to consider the burden in individuals under 5 years of age.IMPORTANCEThe global burden of Clostridioides difficile infection (CDI) is increasing, with notable disparities across regions, age groups, and socioeconomic levels. The higher mortality and disability risks, particularly among older adults, children under 5, and in high socio-demographic index regions, highlight the urgent need for targeted public health interventions and policy adjustments to address these vulnerabilities and reduce the impact of CDI on global health.

The Global Burden of Clostridioides difficile Infections, 2016-2024: A Systematic Review and Meta-Analysis

Background: Clostridioides difficile infection (CDI) is a major cause of healthcare-associated infections globally. Understanding variations in CDI incidence and outcomes across settings, populations, and regions is important for guiding prevention strategies. Aim: The aim of this study was to determine the global epidemiology of CDI to better understand disease burden across settings and geographic regions. Methods: Relevant publications were identified through searches of major databases, including PubMed, Scopus, and Web of Science, published from 1 January 2016 through 24 July 2024. Random effects models were used to pool estimates, and 95% confidence intervals (CIs) were calculated. Results: A total of 59 studies, representing 24 countries across North America, Europe, the Asia-Pacific region, Latin America, and the Middle East, met the inclusion criteria. The incidence of CDI was highest in hospital-onset healthcare facility settings, with 5.31 cases/1000 admissions (95% CI 3.76-7.12) and 5.00 cases/10,000 patient-days (95% CI 3.96-6.15). Long-term care facilities reported 44.24 cases/10,000 patient-days (95% CI 39.57-49.17). Pediatric populations faced a greater risk, with 4.52 cases/1000 admissions (95% CI 0.55-12.17), than adults did at 2.13 (95% CI 1.69-2.61). Recurrence rates were highest for community-acquired CDI at 16.22%. The death rates for the CDI cases tracked for 30 days and of unspecified duration were 8.32% and 16.05%, respectively. Conclusions: This comprehensive review identified healthcare facilities, long-term care, pediatric populations, and North America as disproportionately burdened. This finding provides guidance on priority areas and populations for targeted prevention through antimicrobial stewardship, infection control, and surveillance.

Standard mouse diets lead to differences in severity in infectious and non-infectious colitis

Clostridioides difficile infects the large intestine and can result in debilitating and potentially fatal colitis. The intestinal microbiota is a major factor influencing the severity of disease following infection. Factors like diet that shape microbiota composition and function may modulate C. difficile colitis. Here, we report that mice fed two distinct standard mouse chows (LabDiet 5010 and LabDiet 5053) exhibited significantly different susceptibility to severe C. difficile infection. Both diets are grain-based with comparable profiles of macro and micronutrient composition. Diet 5010-fed mice had severe morbidity and mortality compared to Diet 5053-fed mice despite no differences in C. difficile colonization or toxin production. Furthermore, Diet 5053 protected mice from toxin-induced epithelial damage. This protection was microbiota-dependent as germ-free mice or mice harboring a reduced diversity microbiota fed Diet 5053 were not protected from severe infection. However, cohousing with mice harboring a complex microbiota restored the protective capacity of Diet 5053 but not Diet 5010. Metabolomic profiling revealed distinct metabolic capacities between Diet 5010- and Diet 5053-fed intestinal microbiotas. Diet 5053-mediated protection extended beyond C. difficile infection as Diet 5053-fed mice displayed less severe dextran sodium sulfate-induced colitis than Diet 5010-fed mice, highlighting a potentially broader capacity for Diet 5053 to limit colitis. These findings demonstrate that standard diet formulations in combination with the host microbiota can drive variability in severity of infectious and non-infectious murine colitis systems, and that diet holds therapeutic potential to limit the severity of C. difficile infection through modulating the functional capacity of the microbiota.IMPORTANCEDiet is a major modulator of the microbiota and intestinal health. This report finds that two different standard mouse diets starkly alter the severity of colitis observed in a pathogen-mediated (Clostridioides difficile) and non-infectious (dextran sodium sulfate) mouse colitis experimental systems. These findings in part explain study-to-study variability using these mouse systems to study disease. Since the gut microbiota plays a key role in intestinal homeostasis, diet-derived modulation of the microbiota is a promising avenue to control disease driven by intestinal inflammation and may represent a potential intervention strategy for at-risk patients.

Allosterically switchable network orients β-flap in Clostridioides difficile toxins

Allosteric proteins exhibit a functional response upon ligand binding far from the active site. Clostridioides difficile toxins use allosteric binding by the endogenous cofactor myo-inositol hexakisphosphate to orchestrate self-cleavage from within the target cell. This binding event induces a conformational shift, primarily effecting a lever-like β-flap region, with two known orientations. We uncovered a mechanism for this allosteric transition using extensive atomistic molecular dynamics simulations and computational and experimental mutagenesis. The mechanism relies on a switchable interaction network. The most prominent interaction pair is K600-E743, with K600 interactions explaining ∼70% of the allosteric effect. Rather than gradually morphing between two end states, the interaction network adopts two mutually exclusive configurations in the active and inactive state. Similar switchable networks may explain allostery more broadly. This mechanism in particular could aid in drug development targeting the C. difficile toxins autoproteolysis.

Outcomes of Fecal Microbiota Transplantation for Clostridioides difficile Infection in South Australia

Background

Fecal microbiota transplantation (FMT) sourced from a bank of prescreened anaerobically processed frozen donor stool has been available in South Australia since 2013. This study aimed to evaluate the real-world clinical and safety outcomes of FMT for recurrent, refractory, and/or severe or fulminant Clostridioides difficile infection (CDI) facilitated via this centralized facility.

Methods

Donor screening test data were prospectively collected on all donors who passed prescreening evaluations between April 2013 and August 2023. The South Australian FMT for CDI database prospectively recorded outcomes for consecutive patients who underwent FMT for CDI from August 2013 to May 2023 in South Australia.

Results

An overall 98 potential donors passed prescreening assessments and underwent laboratory screening tests: 32 (33%) had tests that failed, 5 (5%) had incomplete screening, and 61 (62%) passed. Detection of an extended-spectrum β-lactamase-producing organism (9/65, 14%) was the common reason for ineligibility following completion of screening tests. In total 220 cases of CDI were recorded, and follow-up data were available in 216. Primary cure occurred in 84% of cases (182/216): 88% (132/150) for recurrent CDI, 76% (50/66) for refractory CDI, 85% (51/60) for severe disease, and 65% (17/26) for fulminant disease. Repeat FMT was delivered in 23 of 34 cases (68%), with secondary cure in 74% (17/23 cases). Serious adverse events were observed in 6 patients overall (3%). No deaths were directly attributable to FMT.

Conclusions

FMT was safe and efficacious for management of recurrent and refractory CDI over a 10-year period in a real-world prospective Australian cohort. Further studies to optimize the use of FMT for severe and fulminant CDI are warranted.

Association Between Antimicrobials and Pump Proton Inhibitors Consumption with the Incidence of Nosocomial Clostridiodes difficile Infection in High Complexity Hospitals in Costa Rica

Background: Exposure to antimicrobials and Proton Pump Inhibitors (PPIs) are modifiable risk factors for nosocomial Clostridiodes difficile infection (CDI). We investigated the association between these agents and nosocomial CDI over five years. Methods: Nosocomial CDI from January 2017 to December 2021 were included. Consumption trends were analyzed using a simple linear regression model. A correlation analysis was performed using Spearman's test in two ways: without a time interval and with 1-month interval matching. An interrupted time-series method to evaluate the impact of three key temporal breakpoints on CDI incidence rate was performed using the Poisson regression model. Results: A downward trend for cephalexin, ceftriaxone, clindamycin, gentamicin, macrolides, metronidazole, and penicillin sodium was identified. In contrast, an upward trend was recognized for amoxicillin, ceftazidime/avibactam, ertapenem, fluconazole, ketoconazole, levofloxacin, and tigecycline. Among the antimicrobials that showed a positive association between consumption and the incidence of CDI are clindamycin and cephalosporins after immediate consumption. Moreover, macrolides and metronidazole presented a positive correlation, in both immediate and delayed consumption. PPIs consumption did not show changes and was not associated with nosocomial CDI incidence. The interrupted time series analysis showed no changes at the breakpoints selected. Conclusions: Consumption of clindamycin, cephalosporins, and macrolides showed positive association with CDI, despite having a downtrend in consumption. Specific events, such as the COVID-19 pandemic and the implementation of ASP, have had no correlation with CDI. Further analysis is required in Latin America to advance our understanding of risk factors associated with CDI.

Faecal microbiota transplantation for recurrent Clostridiodes difficile infection & its global regulatory landscape

For recurrent Clostridioides difficile infection (rCDI), faecal microbiota transplantation (FMT) is a known and useful treatment that involves introducing faeces from a healthy individual into the digestive tract of a diseased person. Clostridioides difficile is a substantial global health burden due to its high death rate in elderly populations and its ability to produce colitis and diarrhoea. Despite being used since millennia, FMT has recently become more well-known and two FMT products, namely Vowst and Rebyota also received FDA approval. Different nations address regulation in different ways. For instance, FMT is regulated as a drug in the US but is classified as a medicinal product in the UK. The regulatory frameworks among various European countries also vary; a working group, citing FMT as a transplant product, has requested for complete regulation. There are other classifications as well; in Australia, FMT is categorised as a biologic by the Therapeutic Goods Administration. Research indicates that FMT is beneficial in various illnesses, apart from CDI, due to its impact on the gut flora. Challenges include insufficient FMT product characterisation, ethical concerns, and limited hospital accessibility. There are still issues with data accessibility, security, and privacy, especially considering FMT's commercialisation. The official FMT recommendation for recurrent CDI is emphasised from the perspective of public health, with the argument that early implementation could limit antibiotic overuse and prevent antibiotic resistance. Initiatives like the Universal Stool Bank concept aim to streamline donor selection and distribution procedures to minimise operational restrictions.

Clostridioides difficile infections caused by hypervirulent strains: a single-centre real-life study

BACKGROUND AND PURPOSE

Clostridioides difficile infection (CDI) is a leading cause of healthcare-associated infections worldwide, with hypervirulent strains linked to severe disease and higher mortality. This study aims to analyze the epidemiology of CDI at a tertiary-care hospital in Italy and compare clinical outcomes between patients infected with hypervirulent and non-hypervirulent strains.

METHODS

A retrospective comparative study was conducted on patients diagnosed with CDI at ASST Spedali Civili di Brescia, Italy, from January 2015 to June 2023. Hypervirulent strains were identified using the GeneXpert assay as positive for cytotoxin gene (tcdB), binary toxin genes (tcdA and tcdB) and a single nucleotide deletion at position 117 in the tcdC gene and compared to a randomized matched control group with non-hypervirulent CDI. Clinical data were collected and analyzed, with multivariate logistic regression employed to identify risk factors for hypervirulent CDI.

RESULTS

Of 1,059 positive C. difficile specimens, a statistically significant trend between January 2015 to June 2023 was found in the increasing incidence of CDI cases per 1,000 hospital admissions and 10,000 bed-days. Notably, a remarkable increase of hypervirulent strains was recorded in 2021 and 2022 when compared to previous years. A total of 130 patients were analyzed: 62 (47.7%) with hypervirulent CDI and 68 (52.3%) controls. Hypervirulent CDI was associated with higher 30-day mortality (18% vs. 5.8%, p = 0.03). Multivariate analysis showed that hypervirulent CDI significantly increased 30-day mortality risk (OR = 9.915, CI = 2.37-61.05, p = 0.005) and that prior antibiotic therapy was a significant risk factor (OR = 5.49, CI = 1.19-39.96, p = 0.047).

DISCUSSION

Our epidemiological data, while suggesting a potential resurgence in CDI transmission during COVID-19 pandemic, are derived from a single-center experience with limited generalizability to the broader population. Nonetheless, they highlight the need for strengthened antimicrobial stewardship and national surveillance systems to effectively monitor and manage these strains.

Clostridioides difficile infection increases in-hospital mortality, length of stay, and hospital cost but not 30-day mortality in cirrhotic patients

BACKGROUND AND AIM

Clostridioides difficile infection (CDI) is a leading cause of nosocomial infection and is associated with both higher morbidity and mortality. Cirrhotic patients are more susceptible to CDI because of impaired gut immune response, use of proton pump inhibitor, and frequent hospitalization. We aim to investigate the impact of CDI on cirrhotic patients' in-hospital and 30-day mortality, length of stay, and hospital cost.

METHODS

Potentially eligible studies were identified from Embase, Medline, and Web of Sciences databases.

RESULTS

A total of 2320 articles were identified. After reviewing, nine studies reporting in-hospital mortality and three reporting 30-day mortality of cirrhotic patients with CDI versus those without CDI were included. The meta-analysis of nine studies, consisting of 7 746 126 patients, revealed a significant association between CDI and in-hospital mortality in cirrhotic patients with the pooled OR of 1.68 (95% CI 1.29-1.85, I2 94%). Length of stay and hospital cost were also higher in the CDI group (pooled MD of 6.56 days [95% CI 5.75-7.36, I2 94%] and 27.85 (×$1000) [95% CI 10.41-45.29, I2 100%], respectively). The funnel plots for the meta-analysis of the association between CDI and in-hospital mortality, length of stay, and hospitalization cost were not suggestive of publication bias. From three studies consisting of 3694 patients, we found that CDI was not associated with 30-day mortality in cirrhotic patients (pooled OR 1.20, 95% CI 0.75-2.24, I2 74%).

CONCLUSION

CDI is associated with increased in-hospital mortality, length of stay, and hospital costs, but not with 30-day mortality in cirrhotic patients.

Costs and Outcomes of Clostridioides difficile Infections in Germany: A Retrospective Health Claims Data Analysis

INTRODUCTION

Health claims data are a valuable resource for health services research, enabling analysis of the costs of hospitalizations, outpatient visits, procedures, and medications, and providing an improved understanding of the economic burden and underlying cost drivers for a given health condition. Since no recent data were available from Germany on the medical costs and clinical outcomes of Clostridioides difficile infections (CDI), this study assessed the economic burden of CDI and all-cause mortality in adults in Germany.

METHODS

A retrospective cohort study was conducted using a large, anonymized administrative health claims research database from Germany from which an age- and sex-representative sample of 4 million insured persons covered by approximately 60 statutory health insurances was extracted. Propensity score matching was conducted on age, sex, comorbidities, and antibiotic use to identify four matched controls (i.e., patients without CDI) for every eligible adult patient with CDI (i.e., case) in the study cohort. Costs, healthcare resource utilization, and CDI-attributable all-cause mortality were assessed.

RESULTS

Overall, there were 15,342 CDI cases in the study cohort. One-year mortality in CDI cases (45.7%) was more than fourfold that of matched non-CDI controls (11.0%). In the year following the index date, average mortality-adjusted medical costs per person-time for CDI cases were almost fivefold that of matched non-CDI controls, representing a cost difference of €31,459, mainly driven by inpatient treatment. Overall excess costs for CDI cases were estimated at approximately €1.6 billion within 1 year after diagnosis.

CONCLUSIONS

CDI in Germany is associated with a high clinical and economic burden, including significantly higher mortality, costs, and healthcare resource utilization, in patients with CDI versus their matched patients without CDI. This has important implications for patients, healthcare providers, and the healthcare system.

A Review of Therapies for Clostridioides difficile Infection

Clostridioides difficile is an urgent public health threat that affects approximately half a million patients annually in the United States. Despite concerted efforts aimed at the prevention of Clostridioides difficile infection (CDI), it remains a leading cause of healthcare-associated infections. CDI is associated with significant clinical, social, and economic burdens. Therefore, it is imperative to provide optimal and timely therapy for CDI. We conducted a systematic literature review and offer treatment recommendations based on available evidence for the treatment and prevention of CDI.

Diagnosis of Clostridioides difficile infection and impact of testing

Diagnosis of Clostridioides difficile infection (CDI) remains challenging as it involves in the first instance recognition (clinical awareness) of the patients' symptoms for clinical suspicion of CDI to warrant testing, and secondly, different laboratory tests have been described for CDI. Due to the overwhelming amount of information in the literature on CDI tests and their performance, with separately published guidelines, this review aims to provide a comprehensive but concise summary of the current state of CDI diagnostic testing. Current knowledge and the impact of using different laboratory diagnostic procedures for CDI, including the most recommended approach as a two-step algorithm and the concept of diagnostic stewardship, are being discussed. This review provides an updated overview and valuable take-home messages in the field of CDI laboratory testing and highlights that timely diagnosis is important for the clinical management of CDI and that the recommended testing procedures are increasingly becoming more widely accepted.

Retrospective, propensity score--matched study examining the relationship between frailty and Clostridioides difficile infection in a national cohort of US veterans

BACKGROUND

Frailty is often more predictive of disease and mortality compared with chronological age. This study determined the impact of frailty on Clostridioides difficile infection (CDI) risk and outcomes in a national veteran population.

METHODS

This was a retrospective cohort study of CDI and control veteran inpatients and outpatients from fiscal year 2003 to 2018. Baseline frailty was presented as the Veterans Affairs (VA) Frailty Index. Propensity score--matched analyses were conducted to compare CDI risk, CDI health outcomes, and 1-year new-onset frailty-associated conditions.

RESULTS

A total of 11,451 CDI and 11,451 matched control patients were included. Baseline frailty conditions were more common among CDI patients, especially involuntary weight loss (6.0% vs 3.4%, P < .001) and anemia (24.6% vs 18.7%, P < .001). VA Frailty Index was significantly higher for CDI patients (0.13 vs 0.11, P = .019). Frail CDI patients were more likely to experience 30-day mortality (11.3% vs 1.1%, P < .001) and 60-day CDI recurrence (20.4% vs 16.3%, P < .001) compared with non-/prefrail CDI patients. At 1year, CDI patients were significantly more likely to be categorized as frail (19.6% vs 17.0%, P < .001).

CONCLUSIONS

This study demonstrated the potential association between frailty and CDI risk and health outcomes, as well as new-onset frailty diagnoses in patients who develop CDI.

Multicomponent Approaches to Reduce Multidrug-Resistant Organisms in Critical Care: Determining the Ideal Strategy

Although there is ample proof of the advantages of infection prevention and Control (IPC) in acute-care hospitals, there is still some questions about the efficacy of IPC interventions for multidrug-resistant organisms (MDROs), and there is a need for the development of evidence-based practices. No healthcare facility has found a single effective technique to reduce MDRO. However, a multicomponent intervention that included improved barrier protection, chlorhexidine bathing, microbiological monitoring, and staff involvement significantly decreased the likelihood of infection in the patient surroundings with multidrug-resistant organisms. A practical strategy suited to reducing the burden of MDROs and their transmission potential in the critical care unit must be established in light of the global development of AMR. In this review, we summarize key findings of a multicomponent approaches to reduce MDROs in critical care units.

Whole-Genome Sequencing-Based Characterization of Clostridioides difficile Infection Cases at the University Hospital Centre Zagreb

We investigated the intra-hospital distribution of C. difficile strains by whole-genome sequencing (WGS) of isolates collected in 2022 at the University Hospital Centre (UHC) Zagreb. In total, 103 patients with first-episode CDI in 2022 at UHC Zagreb were included, based on the screening stool antigen test for GDH (RidaQuick CD GDH; R-Biopharm AG, Germany), confirmed by Eazyplex C. difficile assays (Eazyplex CD assay; AmplexDiagnostics GmbH, Germany) specific for A, B, and binary toxins. Demographic and clinical data were retrospectively analyzed from electronic medical records. All samples were subjected to WGS analysis. Genetic clusters were formed from isolates with no more than six allelic differences according to core genome MLST. We identified six clusters containing 2-59 isolates with 15 singletons and 30 instances of possible intra-hospital transmission, mostly in the COVID-19 ward. WGS analysis proved useful in identifying clusters of isolates connecting various patient wards with possible transmission routes in the hospital setting. It could be used to support local and national surveillance of CDI infections and their transmission pathways.

Gene Expression Dysregulation in Whole Blood of Patients with Clostridioides difficile Infection

Clostridioides difficile (C. difficile) is a global threat and has significant implications for individuals and health care systems. Little is known about host molecular mechanisms and transcriptional changes in peripheral immune cells. This is the first gene expression study in whole blood from patients with C. difficile infection. We took blood and stool samples from patients with toxigenic C. difficile infection (CDI), non-toxigenic C. difficile infection (GDH), inflammatory bowel disease (IBD), diarrhea from other causes (DC), and healthy controls (HC). We performed transcriptome-wide RNA profiling on peripheral blood to identify diarrhea common and CDI unique gene sets. Diarrhea groups upregulated innate immune responses with neutrophils at the epicenter. The common signature associated with diarrhea was non-specific and shared by various other inflammatory conditions. CDI had a unique 45 gene set reflecting the downregulation of humoral and T cell memory functions. Dysregulation of immunometabolic genes was also abundant and linked to immune cell fate during differentiation. Whole transcriptome analysis of white cells in blood from patients with toxigenic C. difficile infection showed that there is an impairment of adaptive immunity and immunometabolism.

Influence of Antibiotic Exposure Intensity on the Risk of Clostridioides difficile Infection

BACKGROUND

Antibiotics are a strong risk factor for Clostridioides difficile infection (CDI), and CDI incidence is often measured as an important outcome metric for antimicrobial stewardship interventions aiming to reduce antibiotic use. However, risk of CDI from antibiotics varies by agent and dependent on the intensity (ie, spectrum and duration) of antibiotic therapy. Thus, the impact of stewardship interventions on CDI incidence is variable, and understanding this risk requires a more granular measure of intensity of therapy than traditionally used measures like days of therapy (DOT).

METHODS

We performed a retrospective cohort study to measure the independent association between intensity of antibiotic therapy, as measured by the antibiotic spectrum index (ASI), and hospital-associated CDI (HA-CDI) at a large academic medical center between January 2018 and March 2020. We constructed a marginal Poisson regression model to generate adjusted relative risks for a unit increase in ASI per antibiotic day.

RESULTS

We included 35 457 inpatient encounters in our cohort. Sixty-eight percent of patients received at least 1 antibiotic. We identified 128 HA-CDI cases, which corresponds to an incidence rate of 4.1 cases per 10 000 patient-days. After adjusting for known confounders, each additional unit increase in ASI per antibiotic day was associated with 1.09 times the risk of HA-CDI (relative risk = 1.09; 95% CI: 1.06-1.13).

CONCLUSIONS

The ASI was strongly associated with HA-CDI and could be a useful tool in evaluating the impact of antibiotic stewardship on HA-CDI rates, providing more granular information than the more commonly used DOT.

Gut Microbiota and New Microbiome-Targeted Drugs for Clostridioides difficile Infections

Clostridioides difficile is a major causative pathogen for antibiotic-associated diarrhea and C. difficile infections (CDIs) may lead to life-threatening diseases in clinical settings. Most of the risk factors for the incidence of CDIs, i.e., antibiotic use, treatment by proton pump inhibitors, old age, and hospitalization, are associated with dysbiosis of gut microbiota and associated metabolites and, consequently, treatment options for CDIs include normalizing the composition of the intestinal microbiome. In this review, with an introduction to the CDI and its global epidemiology, CDI-associated traits of the gut microbiome and its metabolites were reviewed, and microbiome-targeting treatment options were introduced, which was approved recently as a new drug by the United States Food and Drug Administration (U.S. FDA), rather than a medical practice.

Analysis of factors affecting the length of hospitalization of patients with Clostridioides difficile infection: a cross-sectional study

BACKGROUND

Clostridioides difficile infection (CDI) is an infectious disease caused by the gram-positive, anaerobic bacterium C. difficile. The vulnerable populations for CDI include the elderly, immunocompromised individuals, and hospitalized patients, especially those undergoing antimicrobial therapy, which is a significant risk factor for this infection. Due to its complications and increased resistance to treatment, CDI often leads to longer hospital stays. This study aimed to determine the average length of hospital stay (LOS) of Polish patients with CDI and to identify factors affecting the LOS of infected patients.

METHODS

The study analyzed medical records of adult patients treated with CDI in one of the biggest clinical hospitals in Poland between 2016-2018. Information encompassed the patient's age, LOS results of selected laboratory tests, number of antibiotics used, nutritional status based on Nutritional Risk Screening (NRS 2002), year of hospitalization, presence of diarrhea on admission, systemic infections, additional conditions, and undergone therapies. The systematic collection of these variables forms the foundation for a comprehensive analysis of factors influencing the length of stay.

RESULTS

In the study period, 319 patients with CDI were hospitalized, with a median LOS of 24 days (min-max = 2-344 days). The average LOS was 4.74 days in 2016 (median = 28 days), 4.27 days in 2017 (median = 24 days), and 4.25 days in 2018 (median = 23 days). There was a weak negative correlation (Rho = -0.235, p < 0.001) between albumin level and LOS and a weak positive correlation between NRS and LOS (Rho = 0.219, p < 0.001). Patients admitted with diarrhea, a history of stroke or pneumonia, those taking certain antibiotics (penicillins, cephalosporins, carbapenems, fluoroquinolones, aminoglycosides, colistin), and those using proton pump inhibitors, exhibited longer hospitalizations (all p < 0.001) or unfortunately died (p = 0.008). None of the individual predictors such as albumin level, Nutritional Risk Screen, pneumonia, stroke, and age showed a statistically significant relationship with the LOS (p > 0.05). However, the multivariate regression model explained a substantial portion of the variance in hospitalization length, with an R-squared value of 0.844.

CONCLUSIONS

Hospitalization of a patient with CDI is long. Low albumin levels and increased risk of malnutrition were observed in longer hospitalized patients. Longer hospitalized patients had pneumonia, stroke, or surgery, and were admitted for a reason other than CDI.

Gut Microbial and Metabolic Features Associated With Clostridioides difficile Infection Recurrence in Children

Background

Recurrent Clostridioides difficile infection (CDI) is a critical clinical issue due to the increase in incidence and difficulty in treatment. We aimed to identify gut microbial and metabolic features associated with disease recurrence in a group of pediatric CDI patients.

Methods

A total of 84 children with primary CDI were prospectively enrolled in the study. Fecal samples collected at the initial diagnosis were subjected to 16S rRNA gene sequencing and targeted metabolomics analysis to profile the bacterial composition and metabolome.

Results

Twenty-six of 84 (31.0%) pediatric CDI patients experienced recurrence. The alpha diversity of the fecal microbiota was significantly lower in the recurrent group than in the nonrecurrent group, and the beta diversity was different from that of the nonrecurrent group. Taxonomic profiles revealed that the relative abundances of multiple bacterial taxa significantly differed between the recurrent and nonrecurrent groups. Linear discriminant analysis effect size analysis identified several bacterial genera that discriminated between recurrent and nonrecurrent groups, including Parabacteroides, Coprococcus, Dialister, and Clostridium. Recurrent bacteria presented lower abundances of several short-chain fatty acid (SCFA)-producing bacteria (Faecalibacterium, Butyricicoccus, Clostridium, Roseburia, and Ruminococcus), which were correlated with reduced fecal SCFA levels. In addition, several bile acids, including lithocholic acid (LCA), 12-ketoLCA, trihydroxycholestanoic acid, and deoxycholic acid, were decreased in recurrent patients.

Conclusions

Our study suggests that the differing gut microbiota profiles in pediatric CDI patients may contribute to disease recurrence by modulating SCFA concentrations and bile acid profiles. The gut microbiota and metabolite signatures may be used to predict disease recurrence in children with CDI.

Best Practices in the Management of Clostridioides difficile Infection in Developing Nations

Clostridioides difficile infection (CDI) is a well-known cause of hospital-acquired infectious diarrhea in developed countries, though it has not been a top priority in the healthcare policies of developing countries. In the last decade, several studies have reported a wide range of CDI rates between 1.3% and 96% in developing nations, raising the concern that this could represent a healthcare threat for these nations. This review defines developing countries as those with a human development index (HDI) below 0.8. We aim to report the available literature on CDI epidemiology, diagnostics, management, and prevention in developing countries. We identify limitations for CDI diagnosis and management, such as limited access to CDI tests and unavailable oral vancomycin formulation, and identify opportunities to enhance CDI care, such as increased molecular test capabilities and creative solutions for CDI. We also discuss infection prevention strategies, including antimicrobial stewardship programs and opportunities emerging from the COVID-19 pandemic, which could impact CDI care.

A New Convenient Method to Assess Antibiotic Resistance and Antimicrobial Efficacy against Pathogenic Clostridioides difficile Biofilms

Clostridioides difficile is a widely distributed anaerobic pathogen. C. difficile infection is a serious problem in healthcare. Its biofilms have been found to exhibit biocorrosivity, albeit very little, but sufficient for it to correlate with biofilm growth/health. This work demonstrated the use of a disposable electrochemical biofilm test kit using two solid-state electrodes (a 304 stainless steel working electrode, and a graphite counter electrode, which also served as the reference electrode) in a 10 mL serum vial. It was found that the C. difficile 630∆erm Adp-4 mutant had a minimum inhibitory concentration (MIC) for vancomycin twice that of the 630∆erm wild type strain in biofilm prevention (2 ppm vs. 1 ppm by mass) on 304 stainless steel. Glutaraldehyde, a commonly used hospital disinfectant, was found ineffective at 2% (w/w) for the prevention of C. difficile 630∆erm wild type biofilm formation, while tetrakis(hydroxymethyl)phosphonium sulfate (THPS) disinfectant was very effective at 100 ppm for both biofilm prevention and biofilm killing. These antimicrobial efficacy data were consistent with sessile cell count and biofilm imaging results. Furthermore, the test kit provided additional transient biocide treatment information. It showed that vancomycin killed C. difficile 630∆erm wild type biofilms in 2 d, while THPS only required minutes.

Prevalence of Enteric Pathogens and Antibiotic Resistance: Results of a Six-Year Active Surveillance Study on Patients Admitted to a Teaching Hospital

BACKGROUND

Acute Infectious Diarrhea (AID) and the short- and long-term complications associated with it are major causes of hospitalization worldwide. In Italy, due to a lack of robust surveillance programs, only limited data has been collected on their prevalence and circulation. This study aims to evaluate the resistance pattern of enteric pathogens and their epidemiological trends over a six-year period.

METHODS

This cross-sectional retrospective study was conducted from January 2018 to December 2023. Stool samples were analyzed during routine diagnosis with culture methods, syndromic molecular tests, and enzyme immunoassay.

RESULTS

Bacteria were the most isolated enteric pathogens (62.2%), followed by fungi (29.0%), viruses (8.2%), and parasites (0.6%). Most bacteria were isolated from outpatients (29.5%) and from patients in the Oncology ward (26.2%). The most prevalent target was EPEC (11.1%), followed by C. difficile toxin A/B-producing strains (8.3%), C. jejuni (2.5%), and S. enterica, (1%.). Norovirus and Candida spp. were the most prevalent in pediatric patients (6.5% and 39.6%, respectively). In the last years, enteric pathogens have been a frequent cause of infections characterized by a problematic resistance to common antimicrobials. In our study, S. enterica showed resistance to amikacin, gentamicin, ampicillin, levofloxacin, and ciprofloxacin. C. jejuni was susceptible to all tested drugs.

CONCLUSION

Timely notification of gastroenteric infections is crucial in identifying potential outbreak sources and ensuring strict adherence to food safety and hygiene practices, so as to protect the most vulnerable populations. The present study offers insights into the epidemiological characteristics and the antibiotic susceptibility of the main enteric AID pathogens in order to implement infection control measures in health care settings.

Metagenome-assembled genomes (MAGs) suggest an acetate-driven protective role in gut microbiota disrupted by Clostridioides difficile

Clostridioides difficile may have a negative impact on gut microbiota composition in terms of diversity and abundance, thereby triggering functional changes supported by the differential presence of genes involved in significant metabolic pathways, such as short-chain fatty acids (SCFA). This work has evaluated shotgun metagenomics data regarding 48 samples from four groups classified according to diarrhea acquisition site (community- and healthcare facility-onset) and positive or negative Clostridioides difficile infection (CDI) result. The metagenomic-assembled genomes (MAGs) obtained from each sample were taxonomically assigned for preliminary comparative analysis concerning differences in composition among groups. The predicted genes involved in metabolism, transport, and signaling remained constant in microbiota members; characteristic patterns were observed in MAGs and genes involved in SCFA butyrate and acetate metabolic pathways for each study group. A decrease in genera and species, as well as relative MAG abundance with the presence of the acetate metabolism-related gene, was evident in the HCFO/- group. Increased antibiotic resistance markers (ARM) were observed in MAGs along with the genes involved in acetate metabolism. The results highlight the need to explore the role of acetate in greater depth as a potential protector of the imbalances produced by CDI, as occurs in other inflammatory intestinal diseases.

Commensal-pathogen dynamics structure disease outcomes during Clostridioides difficile colonization

Gastrointestinal colonization by Clostridioides difficile is common in healthcare settings and ranges in clinical presentation from asymptomatic carriage to lethal C. difficile infection (CDI). We used a systems biology approach to investigate why patients colonized with C. difficile have a range of outcomes. Microbiota-humanization of germ-free mice with fecal samples from toxigenic C. difficile carriers revealed a spectrum of virulence among clade 1 lineages and identified commensal Blautia associated with markers of non-pathogenic colonization. Using gnotobiotic mice engrafted with defined human microbiota, we observed strain-specific CDI severity across clade 1 strains. Yet, mice engrafted with a higher diversity community were protected from severe disease across all strains without suppression of C. difficile colonization. These results indicate that when colonization resistance has been breached without overt infection, commensals can attenuate a diversity of virulent strains without inhibiting pathogen colonization, providing insight into determinants of stable C. difficile carriage.

Mortality Attributable to Clostridioides difficile Infection: The Rising Burden of Disease in European Countries

Background and Objectives: Clostridioides difficile infection is a major public health issue, being among the main causes of mortality due to healthcare-associated diarrhea. This study aimed to assess the trends in mortality attributable to Clostridioides difficile infections in European countries over a period of 30 years. Materials and Methods: A descriptive epidemiological study was conducted, with the application of an ecological study design, to evaluate the trends in mortality due to Clostridioides difficile infection in the Central, Eastern, and Western European sub-regions from 1990 to 2019. The Global Burden of Disease study database was used. Trends were evaluated with the joinpoint regression analysis. Results: In both sexes, about 76% of all deaths attributable to Clostridioides difficile infections were recorded in the Western European sub-region in 2019. The age-standardized rates of the burden of Clostridioides difficile infection in 2019 were the highest in the Central European sub-region, followed by the Western European sub-region, while the lowest rates were observed in the Eastern European sub-region. A significantly increasing trend in mortality attributable to Clostridioides difficile infection from 1990 to 2019 was recorded both in males (by +2.1% per year) and females (by +2.8% per year). The burden of Clostridioides difficile infection showed increasing trends in most of the European countries, significantly correlating with the country's development, according to the Human Development Index. Conclusions: The rising burden of Clostridioides difficile infection in European countries in the last few decades suggests a need for improving public health measures, with a focus both on the hospital setting and community.

Fecal microbiota live - jslm (Rebyota™/RBL) for management of recurrent Clostridioides difficile infection

There is an unmet need for effective treatments of Clostridioides difficile infection, an emerging health crisis in the United States. The management of C. difficile infection should include treatment of active infection and a strategy to prevent recurrence. Current gold standard therapy includes oral antibiotics which predispose patients to gut dysbiosis and increase the risk of recurrent infection. Addressing dysbiosis via fecal microbiota transplantation is an active and promising area of research, but studies have lacked standardization which makes outcome and safety data difficult to interpret. Rebyota™, formerly known as RBX2660, is a live biotherapeutic product designed using a standardized protocol and manufacturing process that has been shown to be effective for preventing recurrent C. difficile infection.

[Need for improvement in the care of patients with Clostridioides difficile infections (CDI) - expert opinion in international comparison]

INTRODUCTION

Clostridioides difficile infection (CDI), as a nosocomial disease, is associated with high morbidity and mortality. Even though the incidence of CDI has been declining in Germany in recent years, the individual infection may pose a medical challenge despite therapeutic advances. The aim here is to clarify which gaps practitioners consider to be particularly serious in care and in the existing evidence base.

METHODS

In a moderated workshop of German CDI experts the topics considered as relevant were identified. A survey already conducted in five other countries (Australia, France, Great Britain, Canada, and Italy) was adapted and processed by 27 practitioners. During the evaluation, the topics perceived as particularly important were identified, the statements of the specialist groups were compared and changes in opinion were considered.

RESULTS

27 fully completed questionnaires were evaluated. The need for improvement was primarily seen in the prevention of CDI recurrences (74.1%) and the treatment of recurrences (55.6%). Evidence deficits were noted in the treatment of recurrences (55.6%) and identification of risk factors for recurrences (48.1%). Improving care via fecal microbiota transfer (FMT) was named by 70.4%. For guidelines, more clarity (48.1%) and more regular updates (40.7%) were desired. For patients, better education on appropriate antibiotic use (52.0%) and choice of FMT were desired (48.1%).

SUMMARY

The German expert view and the international assessment is similar, when asked about the need for improvement in care and evidence gaps in the treatment of patients with CDI: The focus is on prevention and therapy of recurrent CDI. The problem of access to FMT is a German peculiarity that seems to need improvement.

Comparative genome analyses of clinical and non-clinical Clostridioides difficile strains

The pathogenic bacterium Clostridioides difficile is a worldwide health burden with increasing morbidity, mortality and antibiotic resistances. Therefore, extensive research efforts are made to unravel its virulence and dissemination. One crucial aspect for C. difficile is its mobilome, which for instance allows the spread of antibiotic resistance genes (ARG) or influence strain virulence. As a nosocomial pathogen, the majority of strains analyzed originated from clinical environments and infected individuals. Nevertheless, C. difficile can also be present in human intestines without disease development or occur in diverse environmental habitats such as puddle water and soil, from which several strains could already be isolated. We therefore performed comprehensive genome comparisons of closely related clinical and non-clinical strains to identify the effects of the clinical background. Analyses included the prediction of virulence factors, ARGs, mobile genetic elements (MGEs), and detailed examinations of the pan genome. Clinical-related trends were thereby observed. While no significant differences were identified in fundamental C. difficile virulence factors, the clinical strains carried more ARGs and MGEs, and possessed a larger accessory genome. Detailed inspection of accessory genes revealed higher abundance of genes with unknown function, transcription-associated, or recombination-related activity. Accessory genes of these functions were already highlighted in other studies in association with higher strain virulence. This specific trend might allow the strains to react more efficiently on changing environmental conditions in the human host such as emerging stress factors, and potentially increase strain survival, colonization, and strain virulence. These findings indicated an adaptation of the strains to the clinical environment. Further, implementation of the analysis results in pairwise genome comparisons revealed that the majority of these accessory genes were encoded on predicted MGEs, shedding further light on the mobile genome of C. difficile. We therefore encourage the inclusion of non-clinical strains in comparative analyses.

PhosphoLipidome Alteration Induced by Clostridioides difficile Toxin B in Enteric Glial Cells

Clostridioides difficile (C. difficile) is responsible for a spectrum of nosocomial/antibiotic-associated gastrointestinal diseases that are increasing in global incidence and mortality rates. The C. difficile pathogenesis is due to toxin A and B (TcdA/TcdB), both causing cytopathic and cytotoxic effects and inflammation. Recently, we demonstrated that TcdB induces cytopathic and cytotoxic (apoptosis and necrosis) effects in enteric glial cells (EGCs) in a dose/time-dependent manner and described the underlying signaling. Despite the role played by lipids in host processes activated by pathogens, to counter infection and/or induce cell death, to date no studies have investigated lipid changes induced by TcdB/TcdA. Here, we evaluated the modification of lipid composition in our in vitro model of TcdB infection. Apoptosis, cell cycle, cell viability, and lipidomic profiles were evaluated in EGCs treated for 24 h with two concentrations of TcdB (0.1 ng/mL; 10 ng/mL). In EGCs treated with the highest concentration of TcdB, not only an increased content of total lipids was observed, but also lipidome changes, allowing the separation of TcdB-treated cells and controls into different clusters. The statistical analyses also allowed us to ascertain which lipid classes and lipid molecular species determine the clusterization. Changes in lipid species containing inositol as polar head and plasmalogen phosphatidylethanolamine emerged as key indicators of altered lipid metabolism in TcdB-treated EGCs. These results not only provide a picture of the phospholipid profile changes but also give information regarding the lipid metabolism pathways altered by TcdB, and this might represent an important step for developing strategies against C. difficile infection.

A Randomized, Double-Blind, Phase 3 Safety and Efficacy Study of Ridinilazole Versus Vancomycin for Treatment of Clostridioides difficile Infection: Clinical Outcomes With Microbiome and Metabolome Correlates of Response

BACKGROUND

Exposure to antibiotics predisposes to dysbiosis and Clostridioides difficile infection (CDI) that can be severe, recurrent (rCDI), and life-threatening. Nonselective drugs that treat CDI and perpetuate dysbiosis are associated with rCDI, in part due to loss of microbiome-derived secondary bile acid (SBA) production. Ridinilazole is a highly selective drug designed to treat CDI and prevent rCDI.

METHODS

In this phase 3 superiority trial, adults with CDI, confirmed with a stool toxin test, were randomized to receive 10 days of ridinilazole (200 mg twice daily) or vancomycin (125 mg 4 times daily). The primary endpoint was sustained clinical response (SCR), defined as clinical response and no rCDI through 30 days after end of treatment. Secondary endpoints included rCDI and change in relative abundance of SBAs.

RESULTS

Ridinilazole and vancomycin achieved an SCR rate of 73% versus 70.7%, respectively, a treatment difference of 2.2% (95% CI: -4.2%, 8.6%). Ridinilazole resulted in a 53% reduction in recurrence compared with vancomycin (8.1% vs 17.3%; 95% CI: -14.1%, -4.5%; P = .0002). Subgroup analyses revealed consistent ridinilazole benefit for reduction in rCDI across subgroups. Ridinilazole preserved microbiota diversity, increased SBAs, and did not increase the resistome. Conversely, vancomycin worsened CDI-associated dysbiosis, decreased SBAs, increased Proteobacteria abundance (∼3.5-fold), and increased the resistome.

CONCLUSIONS

Although ridinilazole did not meet superiority in SCR, ridinilazole greatly reduced rCDI and preserved microbiome diversity and SBAs compared with vancomycin. These findings suggest that treatment of CDI with ridinilazole results in an earlier recovery of gut microbiome health. Clinical Trials Registration.Ri-CoDIFy 1 and 2: NCT03595553 and NCT03595566.

Clostridioides difficile infection: history, epidemiology, risk factors, prevention, clinical manifestations, treatment, and future options

SUMMARYClostridioides difficile infection (CDI) is one of the major issues in nosocomial infections. This bacterium is constantly evolving and poses complex challenges for clinicians, often encountered in real-life scenarios. In the face of CDI, we are increasingly equipped with new therapeutic strategies, such as monoclonal antibodies and live biotherapeutic products, which need to be thoroughly understood to fully harness their benefits. Moreover, interesting options are currently under study for the future, including bacteriophages, vaccines, and antibiotic inhibitors. Surveillance and prevention strategies continue to play a pivotal role in limiting the spread of the infection. In this review, we aim to provide the reader with a comprehensive overview of epidemiological aspects, predisposing factors, clinical manifestations, diagnostic tools, and current and future prophylactic and therapeutic options for C. difficile infection.

Estimating excess mortality and economic burden of Clostridioides difficile infections and recurrences during 2015-2019: the RECUR Germany study

BACKGROUND

Clostridioides difficile infections (CDIs) and recurrences (rCDIs) remain a major public health challenge due to substantial mortality and associated costs. This study aims to generate real-world evidence on the mortality and economic burden of CDI in Germany using claims data between 2015 and 2019.

METHODS

A longitudinal and matched cohort study using retrospective data from Statutory Health Insurance (SHI) was conducted in Germany with the BKK database. Adults diagnosed with CDI in hospital and community settings between 2015 and 2018 were included in the study. Patients had a minimum follow-up of 12-months. All-cause mortality was described at 6-, 12-, and 24-months. Healthcare resource usage (HCRU) and associated costs were assessed at 12-months of follow-up. A cohort of non-CDI patients matched by demographic and clinical characteristics was used to assess excess mortality and incremental costs of HCRU. Up to three non-CDI patients were matched to each CDI patient.

RESULTS

A total of 9,977 CDI patients were included in the longitudinal cohort. All-cause mortality was 32%, 39% and 48% at 6-, 12-, and 24-months, respectively, with minor variations by number of rCDIs. When comparing matched CDI (n = 5,618) and non-CDI patients (n = 16,845), CDI patients had an excess mortality of 2.17, 1.35, and 0.94 deaths per 100 patient-months, respectively. HCRU and associated costs were consistently higher in CDI patients compared to non-CDI patients and increased with recurrences. Total mean and median HCRU cost per patient during follow-up was €12,893.56 and €6,050 in CDI patients, respectively, with hospitalisations representing the highest proportion of costs. A total mean incremental cost per patient of €4,101 was estimated in CDI patients compared to non-CDI patients, increasing to €13,291 in patients with ≥ 3 rCDIs.

CONCLUSIONS

In this real-world study conducted in Germany, CDI was associated with increased risk of death and substantial costs to health systems due to higher HCRU, especially hospitalisations. HCRU and associated costs were exacerbated by rCDIs.

"Primum, non nocere": The Epidemiology of Toxigenic Clostridioides difficile Strains in the Antibiotic Era-Insights from a Prospective Study at a Regional Infectious Diseases Hospital in Eastern Europe

Clostridioides difficile infection (CDI), though identified nearly five decades ago, still remains a major challenge, being associated with significant mortality rates. The strains classified as hypervirulent, notably 027/NAP1/BI, have garnered substantial attention from researchers and clinicians due to their direct correlation with the severity of the disease. Our study aims to elucidate the significance of toxigenic Clostridioides difficile (CD) strains in the clinical and therapeutic aspects of managing patients diagnosed with CDI. We conducted a single-center prospective study, including patients with CDI from north-eastern Romania. We subsequently conducted molecular biology testing to ascertain the prevalence of the presumptive 027/NAP1/BI strain within aforementioned geographic region. The patients were systematically compared and assessed both clinically and biologically, employing standardized and comparative methodologies. The study enrolled fifty patients with CDI admitted between January 2020 and June 2020. Among the investigated patients, 43 (86%) exhibited infection with toxigenic CD strains positive for toxin B genes (tcdB), binary toxin genes (cdtA and cdtB), and deletion 117 in regulatory genes (tcdC), while the remaining 7 (14%) tested negative for binary toxin genes (cdtA and cdtB) and deletion 117 in tcdC. The presence of the presumptive 027/NAP1/BI strains was linked to a higher recurrence rate (35.56%, p = 0.025), cardiovascular comorbidities (65.1% vs. 14.2%, p = 0.016), and vancomycin treatment (55.8% vs. 14.3%, p = 0.049). The findings of our investigation revealed an elevated incidence of colitis attributed to presumptive 027/NAP1/BI. Despite the prevalence of the presumptive 027 strain and its associated heightened inflammation among the patients studied, no significant differences were observed regarding the clinical course or mortality outcomes.

Clostridioides difficile infection, recurrence and the associated healthcare consumption in Sweden between 2006 and 2019: a population-based cohort study

BACKGROUND

Clostridioides difficile infection (CDI) causes a major burden to individuals and society, yet the impact may vary depending on age, sex, underlying comorbidities and where CDI was acquired (hospital or community).

METHODS

This Swedish nationwide population-based cohort study (2006-2019) compared all 43,150 individuals with CDI to their 355,172 matched controls (first year and entire follow-up). Negative binomial regression models compared the cumulated length of stay, number of in-hospital admissions, outpatient visits and prescriptions after the first CDI episode expressed as incidence rate ratios (IRR) and 95% confidence intervals for the entire follow-up.

RESULTS

Overall, 91.6% of CDI cases were hospital acquired, and 16.8% presented with recurrence(s); 74.8%of cases were ≥ 65 years and 54.2% were women. Compared to individuals without CDI, in-hospital stay rates were 18.01 times higher after CDI (95% CI 17.40-18.63, first-year: 27.4 versus 1.6 days), 9.45 times higher in-hospital admission (95% CI 9.16-9.76, first-year: 2.6 versus 1.3 hospitalisations), 3.94 times higher outpatient visit (95% CI 3.84-4.05, first-year: 4.0 versus 1.9 visits) and 3.39 times higher dispensed prescriptions rates (95% CI 3.31-3.48, first-year: 25.5 versus 13.7 prescriptions). For all outcomes, relative risks were higher among the younger (< 65 years) than the older (≥ 65 years), and in those with fewer comorbidities, but similar between sexes. Compared to those without recurrence, individuals with recurrence particularly showed a higher rate of hospital admissions (IRR = 1.18, 95% 1.12-1.24). Compared to community-acquired CDI, those with hospital-acquired CDI presented with a higher rate of hospital admissions (IRR = 7.29, 95% CI 6.68-7.96) and a longer length of stay (IRR = 7.64, 95% CI 7.07-8.26).

CONCLUSION

CDI was associated with increased health consumption in all affected patient groups. The majority of the CDI burden could be contributed to hospital-acquired CDI (~ 9/10), older patients (~ 3/4) and those with multiple comorbidities (~ 6/10 Charlson score ≥ 3), with 1/5 of the total CDI burden contributed to individuals with recurrence. Yet, relatively speaking the burden was higher among the younger and those with fewer comorbidities, compared to their peers without CDI.

Case Series: Efficacy of Polyclonal Intravenous Immunoglobulin for Refractory Clostridioides difficile Infection

BACKGROUND

Intravenous immunoglobulin (IVIg) for Clostridioides difficile infection (CDI) no longer features in treatment guidelines. However, IVIg is still used by some clinicians for severe or recurrent CDI (rCDI) cases. The main objective of this study was to investigate the efficacy of IVIg and to identify possible predictors of disease resolution post IVIg administration for patients with CDI.

METHODS

This retrospective observational cohort study of patients ≥2 years old hospitalised with severe, relapsing, or rCDI treated with IVIg therapy was performed in a large UK tertiary hospital between April 2018 and March 2023. Scanned electronic notes from patient admissions and clinical reporting systems were used to collect relevant data.

RESULTS

In total, 20/978 patients diagnosed with CDI over the 5-year study were treated with IVIg. Twelve (60%) had hospital-onset CDI. Eleven of the twenty patients (55%) responded to treatment, with a mean of 8.6 (SD 10.7) days to disease resolution. Sixteen (80%) patients were treated for severe CDI and four (20%) for rCDI (n = 3) and relapsing CDI (n = 1). There were no statistically significant differences in possible independent predictors of disease resolution post IVIg administration between groups. There was an average of 6.2 (4.9) days to IVIg administration after diagnosis with no difference between responders and non-responders (p = 0.88) and no further significant difference in additional indicators. Four (36%) of the responders were immunosuppressed compared to just one (11%) of the non-responders (p = 0.15). Six of the responders (two with recurrent and four with severe CDI) improved rapidly within 2 days, and three of these were immunosuppressed.

CONCLUSION

We observed disease resolution post IVIg therapy in over 50% of patients with refractory CDI. Our data also support a potential enhanced effect of IVIg in immunosuppressed individuals. Thus, the role of IVIg for CDI treatment, particularly in the immunosuppressed, warrants future case-control studies coupled to mechanistic investigations to improve care for this ongoing significant healthcare-associated infection.

[Fecal Microbiota Transfer (FMT) in Germany - Status and Perspective]

INTRODUCTION

Fecal microbiota transfer (FMT) is a treatment to modulate the gastrointestinal microbiota. Its use in recurrent Clostridioides difficile infection (rCDI) is established throughout Europe and recommended in national and international guidelines. In Germany, the FMT is codeable in the hospital reimbursement system. A comprehensive survey on the frequency of use based on this coding is missing so far.

MATERIAL AND METHODOLOGY

Reports of the Institute for Hospital Remuneration (InEK), the Federal Statistical Office (DESTATIS), and hospital quality reports 2015-2021 were examined for FMT coding and evaluated in a structured expert consultation.

RESULTS

Between 2015 and 2021, 1,645 FMT procedures were coded by 175 hospitals. From 2016 to 2018, this was a median of 293 (274-313) FMT annually, followed by a steady decline in subsequent years to 119 FMT in 2021. Patients with FMT were 57.7% female, median age 74 years, and FMT was applied colonoscopically in 72.2%. CDI was the primary diagnosis in 86.8% of cases, followed by ulcerative colitis in 7.6%.

DISCUSSION

In Germany, FMT is used less frequently than in the European comparison. One application hurdle is the regulatory classification of FMT as a non-approved drug, which leads to significantly higher costs in manufacturing and administration and makes reimbursement difficult. The European Commission recently proposed a regulation to classify FMT as a transplant. This could prospectively change the regulatory situation of FMT in Germany and thus contribute to a nationwide offer of a therapeutic procedure recommended in guidelines.

Clostridioides difficile recurrence in individuals with and without cancer: a Swedish population-based cohort study

PURPOSE

Patients with cancer are vulnerable to Clostridioides difficile infection (CDI) due to their disease, treatment and regular hospital contact, yet if CDI-recurrence is more common remains unclear, and differences among cancer types remain unexplored.

METHODS

This Swedish nationwide population-based cohort included all 43,150 individuals with recorded CDI (2006-2019) to assess CDI-recurrence in individuals with and without cancer, with binary multivariable logistic regression, stratified by anatomical location, and survival status.

RESULTS

Compared to those without cancer (N = 29,543), ongoing cancer (diagnosis < 12 months; N = 3,882) was associated with reduced recurrence (OR = 0.81, 95% CI 0.73-0.89), while there was no association with cancer history (diagnosis ≥ 12 months; N = 9,725). There was an increased 8-week all-cause mortality (Ongoing cancer: OR = 1.58, 95% CI 1.43-1.74; Cancer history: OR = 1.45, 95% CI 1.36-1.55) compared to those without cancer. Among CDI-survivors, those with ongoing cancer presented with a decreased odds of recurrence (OR = 0.84, 95% CI 0.76-0.94), compared to those without cancer history, with no association for those with cancer history (OR = 1.04, 95% CI 0.97-1.1). Large variations were seen across cancer types, with the highest observed proportion of recurrence in oral and mesothelial cancer, and the lowest for esophageal cancer, although no statistically significant OR were found.

CONCLUSION

The population-based study indicates that individuals with cancer may have fewerrecurrences than expected, yet variations by cancer type were large, and mortality was high.

Microbiota-Based Therapeutics as New Standard-of-Care Treatment for Recurrent Clostridioides difficile Infection

Background

Clostridioides difficile (C. difficile) is a spore-forming bacterial species that ubiquitously exists in the environment. Colonization by C. difficile is highly prevalent in infants, while fewer than 5% of adults are asymptomatic carriers. Disruption of the microbiome, such as through antibiotic treatment, triggers the germination of bacterial spores into numerous vegetative cells. These cells then produce enterotoxins that result in watery diarrhea and colonic inflammation. If left untreated, C. difficile infection (CDI) can lead to pseudomembranous colitis with the potentially life-threatening complication of toxic megacolon.

Summary

Over the past few decades, the incidence, morbidity, and mortality associated with CDIs have increased. They have emerged as the primary cause of nosocomial gastrointestinal infections in industrialized countries, posing a significant burden on healthcare systems. Despite antibiotics often being the cause of CDIs, they remain the standard treatment. However, a considerable number of patients treated with antibiotics will experience recurrent CDI (rCDI). Microbiota-based therapies targeting the core issue of CDI - antibiotic-induced dysbiosis - hold promise for rCDI treatment. While data for probiotics are insufficient, numerous studies have highlighted the effectiveness of fecal microbiota transplantation (FMT) as a safe and viable therapeutic option for rCDI. This approach is now endorsed by multiple guidelines. Nonetheless, regulatory prerequisites, such as comprehensive stool donor screening, restrict the widespread adoption of FMT beyond specialized centers. Recently, the US Food and Drug Administration has approved two commercial microbiota-based therapeutics to prevent CDI recurrence. These therapeutics are available by prescription in the USA. RBX2660 (REBYOTA™) comprises a diverse consortium of live microbes derived from human stool and is administered via enema. On the other hand, SER-109 (VOWST™) is an orally administered spore-based medication. In this review, we discuss the potential of microbiota-based treatments for rCDI against the background of medico-legal challenges associated with classical FMT.

Key Messages

FMT has emerged as a highly effective cure for rCDI. Nonetheless, regulatory prerequisites and laborious preparation procedures impede its widespread use. The establishment of ready-to-use microbiota-based therapeutics in clinical practice is necessary. In the USA, the recent approval of the first two commercial medications, including a spore-based oral preparation, marks a significant step forward.

Novel insights into phage biology of the pathogen Clostridioides difficile based on the active virome

The global pathogen Clostridioides difficile is a well-studied organism, and researchers work on unraveling its fundamental virulence mechanisms and biology. Prophages have been demonstrated to influence C. difficile toxin expression and contribute to the distribution of advantageous genes. All these underline the importance of prophages in C. difficile virulence. Although several C. difficile prophages were sequenced and characterized, investigations on the entire active virome of a strain are still missing. Phages were mainly isolated after mitomycin C-induction, which does not resemble a natural stressor for C. difficile. We examined active prophages from different C. difficile strains after cultivation in the absence of mitomycin C by sequencing and characterization of particle-protected DNA. Phage particles were collected after standard cultivation, or after cultivation in the presence of the secondary bile salt deoxycholate (DCA). DCA is a natural stressor for C. difficile and a potential prophage-inducing agent. We also investigated differences in prophage activity between clinical and non-clinical C. difficile strains. Our experiments demonstrated that spontaneous prophage release is common in C. difficile and that DCA presence induces prophages. Fourteen different, active phages were identified by this experimental procedure. We could not identify a definitive connection between clinical background and phage activity. However, one phage exhibited distinctively higher activity upon DCA induction in the clinical strain than in the corresponding non-clinical strain, although the phage is identical in both strains. We recorded that enveloped DNA mapped to genome regions with characteristics of mobile genetic elements other than prophages. This pointed to mechanisms of DNA mobility that are not well-studied in C. difficile so far. We also detected phage-mediated lateral transduction of bacterial DNA, which is the first described case in C. difficile. This study significantly contributes to our knowledge of prophage activity in C. difficile and reveals novel aspects of C. difficile (phage) biology.

Culture-independent detection of low-abundant Clostridioides difficile in environmental DNA via PCR

Clostridioides difficile represents a major burden to public health. As a well-known nosocomial pathogen whose occurrence is highly associated with antibiotic treatment, most examined C. difficile strains originated from clinical specimen and were isolated under selective conditions employing antibiotics. This suggests a significant bias among analyzed C. difficile strains, which impedes a holistic view on this pathogen. In order to support extensive isolation of C. difficile strains from environmental samples, we designed a detection PCR that targets the hpdBCA-operon and thereby identifies low abundances of C. difficile in environmental samples. This operon encodes the 4-hydroxyphenylacetate decarboxylase, which catalyzes the production of the antimicrobial compound para-cresol. Amplicon-based analyses of diverse environmental samples demonstrated that the designed PCR is highly specific for C. difficile and successfully detected C. difficile despite its absence in general 16S rRNA gene-based detection strategies. Further analyses revealed the potential of the hpdBCA detection PCR sequence for initial phylogenetic classification, which allows assessment of C. difficile diversity in environmental samples via amplicon sequencing. Our findings furthermore showed that C. difficile strains isolated under antibiotic treatment from environmental samples were originally dominated by other strains according to PCR amplicon results. This provided evidence for selective cultivation of under-represented but antibiotic-resistant isolates. Thereby, we revealed a substantial bias in C. difficile isolation and research.IMPORTANCEClostridioides difficile is a main cause of diarrheic infections after antibiotic treatment with serious morbidity and mortality worldwide. Research on this pathogen and its virulence has focused on bacterial isolation from clinical specimens under antibiotic treatment, which implies a substantial bias in isolated strains. Comprehensive studies, however, require an unbiased strain collection, which is accomplished by isolation of C. difficile from diverse environmental samples and avoidance of antibiotic-based enrichment strategies. Thus, isolation can significantly benefit from our C. difficile-specific detection PCR, which rapidly verifies C. difficile presence in environmental samples and further allows estimation of the C. difficile diversity by using next-generation sequencing.

Genomic surveillance of Clostridioides difficile transmission and virulence in a healthcare setting

Clostridioides difficile infection (CDI) is a major cause of healthcare-associated diarrhea, despite the widespread implementation of contact precautions for patients with CDI. Here, we investigate strain contamination in a hospital setting and the genomic determinants of disease outcomes. Across two wards over 6 months, we selectively cultured C. difficile from patients (n = 384) and their environments. Whole-genome sequencing (WGS) of 146 isolates revealed that most C. difficile isolates were from clade 1 (131/146, 89.7%), while only one isolate of the hypervirulent ST1 was recovered. Of culture-positive admissions (n = 79), 19 (24%) patients were colonized with toxigenic C. difficile on admission to the hospital. We defined 25 strain networks at ≤2 core gene single nucleotide polymorphisms; two of these networks contain strains from different patients. Strain networks were temporally linked (P < 0.0001). To understand the genomic correlates of the disease, we conducted WGS on an additional cohort of C. difficile (n = 102 isolates) from the same hospital and confirmed that clade 1 isolates are responsible for most CDI cases. We found that while toxigenic C. difficile isolates are associated with the presence of cdtR, nontoxigenic isolates have an increased abundance of prophages. Our pangenomic analysis of clade 1 isolates suggests that while toxin genes (tcdABER and cdtR) were associated with CDI symptoms, they are dispensable for patient colonization. These data indicate that toxigenic and nontoxigenic C. difficile contamination persist in a hospital setting and highlight further investigation into how accessory genomic repertoires contribute to C. difficile colonization and disease.

IMPORTANCE

Clostridioides difficile infection remains a leading cause of hospital-associated diarrhea, despite increased antibiotic stewardship and transmission prevention strategies. This suggests a changing genomic landscape of C. difficile. Our study provides insight into the nature of prevalent C. difficile strains in a hospital setting and transmission patterns among carriers. Longitudinal sampling of surfaces and patient stool revealed that both toxigenic and nontoxigenic strains of C. difficile clade 1 dominate these two wards. Moreover, quantification of transmission in carriers of these clade 1 isolates underscores the need to revisit infection prevention measures in this patient group. We identified unique genetic signatures associated with virulence in this clade. Our data highlight the complexities of preventing transmission of this pathogen in a hospital setting and the need to investigate the mechanisms of in vivo persistence and virulence of prevalent lineages in the host gut microbiome.

The combined effect of systemic antibiotics and proton pump inhibitors on Clostridioides difficile infection and recurrence

BACKGROUND

Antibiotics and proton pump inhibitors (PPI) are recognized risk factors for acquisition and recurrence of Clostridioides difficile infection (CDI), yet combined effects remain unclear.

OBJECTIVES

To assess the short- and long-term effects of antibiotics and PPIs on CDI risk and recurrence.

METHODS

Population-based study including all 43 152 patients diagnosed with CDI in Sweden (2006-2019), and 355 172 matched population controls without CDI. The impact of antibiotics and PPIs on CDI risk and recurrence was explored for recent (0-30 days) and preceding (31-180 days) use prior to their first CDI diagnosis, using multivariable conditional logistic regression presented as odds ratios (ORs) and 95% confidence interval, adjusted for demographics, comorbidities and other drugs.

RESULTS

Compared to controls, the combined effect of recent PPIs and antibiotics [ORAB+PPI = 17.51 (17.48-17.53)] on CDI risk was stronger than the individual effects [ORAB = 15.37 (14.83-15.93); ORPPI = 2.65 (2.54-2.76)]. Results were less pronounced for exposure during the preceding months. Dose-response analyses showed increasing exposure correlated with CDI risk [recent use: ORAB = 6.32 (6.15-6.49); ORPPI = 1.65 (1.62-1.68) per prescription increase].Compared to individuals without recurrence (rCDI), recent [ORAB = 1.30 (1.23-1.38)] and preceding [ORAB = 1.23 (1.16-1.31); ORPPI = 1.12 (1.03-1.21)] use also affected the risk of recurrence yet without significant interaction between both. Recent macrolides/lincosamides/streptogramins; other antibacterials including nitroimidazole derivates; non-penicillin beta lactams and quinolones showed the strongest association with CDI risk and recurrence, particularly for recent use. PPI use, both recent and preceding, further increased the CDI risk associated with almost all antibiotic classes.

CONCLUSION

Recent and less recent use of PPIs and systemic antibiotics was associated with an increased risk of CDI, particularly in combination.

Clostridioides difficile infections, recurrences, and clinical outcomes in real-world settings from 2015 to 2019: The RECUR England study

OBJECTIVE

To estimate the epidemiological and clinical burden of Clostridioides difficile infections (CDIs) and recurrences (rCDIs) in England.

METHODS

This retrospective study included adult patients diagnosed with CDI (community or hospital settings) over 2015-2019 from Clinical Practice Research Datalink and Hospital Episode Statistics databases. Incidences of CDI and rCDI were determined annually. Time to subsequent rCDI was estimated by Kaplan-Meier method. Rates of complications were assessed within 12 months from index episode. Association of risk factors with complications was evaluated using a Cox regression model.

RESULTS

A total of 52,443 CDI episodes were recorded among 36,913 patients. Of these, 75% were aged ≥65 years, 59% were women; 73% were treated in community settings. CDI incidence remained stable (111 episodes per 100,000 patients in 2019). Around 21% of patients had ≥1 rCDI. Sepsis (12%) was the most common complication, followed by colectomy and ulcerative colitis. Age, gender, comorbidities, rCDI, preindex medical procedures, hospitalizations and consultations, and CDI treatment in hospital, were found to increase the risk of complication.

CONCLUSIONS

CDI remains a concern in England. The study highlights the importance of managing primary and rCDI episodes via effective and improved therapies to prevent fatal complications.

Advances in Therapeutic Strategies for the Management of Clostridioides difficile Infection

The infection caused by Clostridioides difficile represents one of the bacterial infections with the greatest increase in incidence among nosocomial infections in recent years. C. difficile is a Gram-positive bacterium able to produce toxins and spores. In some cases, infection results in severe diarrhoea and fulminant colitis, which cause prolonged hospitalisation and can be fatal, with repercussions also in terms of health economics. C. difficile is the most common cause of antibiotic-associated diarrhoea in the healthcare setting. The problem of bacterial forms that are increasingly resistant to common antibiotic treatments is also reflected in C. difficile infection (CDI). One of the causes of CDI is intestinal dysmicrobialism induced by prolonged antibiotic therapy. Moreover, in recent years, the emergence of increasingly virulent strains resistant to antibiotic treatment has made the picture even more complex. Evidence on preventive treatments to avoid recurrence is unclear. Current guidelines indicate the following antibiotics for the treatment of CDI: metronidazole, vancomycin, and fidaxomycin. This short narrative review provides an overview of CDI, antibiotic resistance, and emerging treatments.

A Real-World Study on the Clinical Characteristics, Outcomes, and Relationship between Antibiotic Exposure and Clostridioides difficile Infection

Clostridioides difficile is a Gram-positive bacteria that causes nosocomial infections, significantly impacting public health. In the present study, we aimed to describe the clinical characteristics, outcomes, and relationship between antibiotic exposure and Clostridioides difficile infection (CDI) in patients based on reports from two databases. Thus, we conducted a retrospective study of patients diagnosed with CDI from Sibiu County Clinical Emergency Hospital (SCCEH), Romania, followed by a descriptive analysis based on spontaneous reports submitted to the EudraVigilance (EV) database. From 1 January to 31 December 2022, we included 111 hospitalized patients with CDI from SCCEH. Moreover, 249 individual case safety reports (ICSRs) from EVs were analyzed. According to the data collected from SCCEH, CDI was most frequently reported in patients aged 65-85 years (66.7%) and in females (55%). In total, 71.2% of all patients showed positive medical progress. Most cases were reported in the internal medicine (n = 30, 27%), general surgery (n = 26, 23.4%), and infectious disease (n = 22, 19.8%) departments. Patients were most frequently exposed to ceftriaxone (CFT) and meropenem (MER). Also, in the EV database, most CDI-related ADRs were reported for CFT, PIP/TAZ (piperacillin/tazobactam), MER, and CPX (ciprofloxacin). Understanding the association between previous antibiotic exposure and the risk of CDI may help update antibiotic stewardship protocols and reduce the incidence of CDI by lowering exposure to high-risk antibiotics.

Defined microbial communities and their soluble products protect mice from Clostridioides difficile infection

Clostridioides difficile is the leading cause of antibiotic-associated infectious diarrhea. The development of C.difficile infection is tied to perturbations of the bacterial community in the gastrointestinal tract, called the gastrointestinal microbiota. Repairing the gastrointestinal microbiota by introducing lab-designed bacterial communities, or defined microbial communities, has recently shown promise as therapeutics against C.difficile infection, however, the mechanisms of action of defined microbial communities remain unclear. Using an antibiotic- C.difficile mouse model, we report the ability of an 18-member community and a refined 4-member community to protect mice from two ribotypes of C.difficile (CD027, CD078; p < 0.05). Furthermore, bacteria-free supernatant delivered orally to mice from the 4-member community proteolyzed C.difficile toxins in vitro and protected mice from C.difficile infection in vivo (p < 0.05). This study demonstrates that bacteria-free supernatant is sufficient to protect mice from C.difficile; and could be further explored as a therapeutic strategy against C.difficile infection.