High Throughput Repurposing Screen Reveals Compounds with Activity Against Toxoplasma gondii Bradyzoites

Toxoplasma gondii causes widespread chronic infections that are not cured by current treatments due to inability to affect semi-dormant bradyzoite stages within tissue cysts. To identify compounds to eliminate chronic infection, we developed a HTS using a recently characterized strain of T. gondii that undergoes efficient conversion to bradyzoites in intro. Stage-specific expression of luciferase was used to selectively monitor growth inhibition of bradyzoites by the Library of Pharmacological Active Compounds, consisting of 1,280 drug-like compounds. We identified 44 compounds with >50% inhibitory effects against bradyzoites, including new highly potent compounds, several of which have precedent for antimicrobial activity. Subsequent characterization of the compound Sanguinarine sulfate revealed potent and rapid killing against in vitro produced bradyzoites and bradyzoites harvested from chronically infected mice. These findings provide a platform for expanded screening and identify promising compounds for further preclinical development against T. gondii bradyzoites responsible for chronic infection.

Duration from start of antibiotic exposure to onset of Clostridioides difficile infection for different antibiotics in a non-outbreak setting

BACKGROUND

Antibiotic treatment is a well-known risk factor for Clostridioides difficile infection (CDI). The time from start of antibiotic exposure to onset of CDI for different antibiotics is sparsely studied. CDI with onset in the community is often treatable without in-hospital care while CDI patients treated in hospital need isolation, resulting in higher costs and infection control measures.

OBJECTIVES

To determine the time from start of antibiotic exposure to onset of healthcare facility-associated CDI for different antibiotics.

METHODS

Time between antibiotic exposure and disease onset was evaluated retrospectively with chart reading in a two-centre Swedish setting. A case was attributed to an antibiotic group if this represented more than 2/3 of total antibiotic exposure 30 days before onset of CDI.

RESULTS

Cephalosporins caused CDI faster (mean 7.6 days), and more often during ongoing antibiotic therapy (81% of the cases) than any other antibiotic group. All other common agents had between 2-3 times longer period between start of exposure to onset of CDI (quinolones more than 3 times).

CONCLUSIONS

The time gap between antibiotic exposure and onset of CDI is markedly different between different antibiotics. Decreased cephalosporin use could delay onset of healthcare facility-associated CDI and limit infections with onset within the hospital. This might decrease costs for inpatient care, need of infection control measures and shortage of beds in the hospital.

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.

Efficacy of Fecal Microbiota, Live-jslm (REBYOTA®), Among Patients Exposed to Non-Clostridioides difficile Infection Antibiotics: Post Hoc Subgroup Analysis of a Phase 2 Open-Label Study

Background

Antibiotic use is a major risk factor for recurrent Clostridioides difficile infection (CDI) due to the associated disruption in gut microbiota. Fecal microbiota, live-jslm (REBYOTA®; RBL, previously RBX2660), is the first microbiota-based live biotherapeutic approved by the US Food and Drug Administration to prevent recurrent CDI in adults following standard-of-care antibiotic treatment. To investigate the impact of non-CDI antibiotics on the durability of RBL, a subgroup analysis was conducted on PUNCH™ Open-Label study participants who received non-CDI antibiotics during the period between RBL administration and up to 2 years after.

Methods

Participants in PUNCH™ Open-Label who received non-CDI antibiotics after RBL administration were included in this subgroup analysis. Treatment response was defined as the absence of CDI diarrhea needing retreatment at the last evaluable time point (8 weeks, 6 months, 1 year, or 2 years) after RBL administration.

Results

Among participants from PUNCH™ Open-Label, 43 received non-CDI antibiotics after RBL administration but before CDI recurrence as evaluated over a 2-year period. Across all evaluable time points, 86% (37/43) of participants had a treatment response regardless of when non-CDI antibiotic exposure occurred. Treatment response was sustained for a median 470 days (IQR, 212-648) from the first day of non-CDI antibiotic use. Most participants (5/6) with CDI recurrences received a high-risk antibiotic.

Conclusions

RBL remained efficacious in participants with a history of recurrent CDI after subsequent non-CDI antibiotic exposure.

Clinical Trials Registration

NCT02589847 (https://clinicaltrials.gov/study/NCT02589847).

Comparison of Cefazolin and Ceftriaxone Enterobacterales Susceptibilities for Inpatient Treatment of Urinary Tract Infections and Risk of Hospital-onset Clostridioides difficile Infection

PURPOSE

Urinary tract infection (UTI) is the second most common indication for antibiotic therapy among inpatients in the United States. Ceftriaxone, a third-generation cephalosporin, is habitually chosen to treat inpatient UTIs due to familiarity, cost, and perceived safety. However, third-generation cephalosporins increase the risk of health care facility-onset Clostridioides difficile infection (HOCDI) more than any other antibiotic group, while no statistical risk exists for first-generation cephalosporins. Recent evidence comparing Enterobacterales susceptibility for first- and third-generation cephalosporins in urinary specimens in the United States is limited. This analysis assessed the comparative activity of cefazolin and ceftriaxone for Enterobacterales urinary isolates and incidence of HOCDI to determine the usefulness of cefazolin as an empirical agent to manage inpatient UTI and limit ceftriaxone collateral damage.

METHODS

This was a retrospective single-center observational study. Microbiologic susceptibility data were analyzed for Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis urinary specimens taken from adult inpatients admitted from January 1, 2022, to December 31, 2022. Primary outcome was incidence of E coli, K pneumoniae, and P mirabilis susceptibility to cefazolin in uncomplicated UTI (MIC <16 µg/mL). Secondary outcomes include susceptibility for complicated UTI and HOCDI risk associated with cefazolin and ceftriaxone.

FINDINGS

A total of 1150 urine samples were identified as E coli, K pneumoniae, and P mirabilis in 2022. Susceptibility to cefazolin was observed in 1064 (92.5%) of 1150 isolates using the MIC breakpoint for uncomplicated UTI and to ceftriaxone in 1115 (97.0%) of 1150 isolates (P < 0.001). From 2016 to 2022, either cefazolin or ceftriaxone was administered in 26,462 inpatient admissions, with HOCDI diagnoses occurring in 89 admissions. HOCDI developed in 78 admissions (0.40%) with ceftriaxone exposure, and 11 cases (0.15%) developed in cefazolin-exposed admissions (adjusted odds ratio, 2.44; 95% CI, 1.25-4.76; P < 0.001).

IMPLICATIONS

Cefazolin exhibits high susceptibility for uropathogens commonly implicated in cases of uncomplicated UTI, the most common UTI diagnosis among inpatients. Although ceftriaxone shows a higher susceptibility rate against these common uropathogens, it more than doubles the risk for HOCDI compared with cefazolin. For institutions evaluating opportunities to reduce ceftriaxone use to limit associated collateral damage such as HOCDI, use of cefazolin for uncomplicated UTI may be evaluated by using local susceptibility data.

No evidence of difference in mortality with amoxicillin versus co-amoxiclav for hospital treatment of community-acquired pneumonia

OBJECTIVES

Current guidelines recommend broad-spectrum antibiotics for high-severity community-acquired pneumonia (CAP), potentially contributing to antimicrobial resistance (AMR). We aim to compare outcomes in CAP patients treated with amoxicillin (narrow-spectrum) versus co-amoxiclav (broad-spectrum), to understand if narrow-spectrum antibiotics could be used more widely.

METHODS

We analysed electronic health records from adults (≥16 y) admitted to hospital with a primary diagnosis of pneumonia between 01-January-2016 and 30-September-2023 in Oxfordshire, United Kingdom. Patients receiving baseline ([-12 h,+24 h] from admission) amoxicillin or co-amoxiclav were included. The association between 30-day all-cause mortality and baseline antibiotic was examined using propensity score (PS) matching and inverse probability treatment weighting (IPTW) to address confounding by baseline characteristics and disease severity. Subgroup analyses by disease severity and sensitivity analyses with missing covariates imputed were also conducted.

RESULTS

Among 16,072 admissions with a primary diagnosis of pneumonia, 9685 received either baseline amoxicillin or co-amoxiclav. There was no evidence of a difference in 30-day mortality between patients receiving initial co-amoxiclav vs. amoxicillin (PS matching: marginal odds ratio 0.97 [0.76-1.27], p = 0.61; IPTW: 1.02 [0.78-1.33], p = 0.87). Results remained similar across stratified analyses of mild, moderate, and severe pneumonia. Results were also similar with missing data imputed. There was also no evidence of an association between 30-day mortality and use of additional macrolides or additional doxycycline.

CONCLUSIONS

There was no evidence of co-amoxiclav being advantageous over amoxicillin for treatment of CAP in 30-day mortality at a population-level, regardless of disease severity. Wider use of narrow-spectrum empirical treatment of moderate/severe CAP should be considered to curb potential for AMR.

Microbiota restoration therapies for recurrent Clostridioides difficile infection reach an important new milestone

Microbiota restoration therapy has become a standard treatment for recurrent Clostridioides difficile infection (rCDI). In this article, we review the studies supporting the licensure of two live biotherapeutic products (LBPs) designed to prevent rCDI and to provide clinicians with a perspective on their differences. PubMed was reviewed on 1 October 2023, for all papers published concerning the current Food and Drug Administration allowance of the use of fecal microbiota transplantation (FMT) and the studies that led to the licensure of RBX2660 (REBYOTA™), generic name, fecal microbiota, live-jslm, and SER-109 (VOWST™), generic name, fecal microbiota spores, live-brpk. OpenBiome continues to produce fecal products for patients with rCDI at their treatment sites, and the American Gastroenterology Association has a National Registry focused on long-term safety of administering fecal microbiota products. The science behind the licensing of fecal microbiota, live-jslm, a consortium of fecal anaerobes found in stool augmented with strains of Bacteroidetes and fecal microbiota spores, live-brpk, a mixture of 50 species of purified Firmicutes spores is reviewed. Both products appear to be safe in clinical trials and effective in reducing rCDI episodes by mechanisms established for FMT, including normalization of α- and β-diversity of the microbiome and by increasing fecal secondary bile acids. The different makeup of the two LBPs suggests that rCDI responds to a variety of engrafting microbiota which explains why nearly all donors in FMT of rCDI are generally effective. Fecal microbiota, live-jslm has also been shown to successfully treat rCDI in elderly patients with advanced comorbidities. With the licensure of two novel LBPs, we are entering a new phase of microbiota replacement therapy. Having standardized manufacturing and proper monitoring of products, harnessing the microbiome to control and prevent disease has a new beginning.

Insight into the Mechanism of Lysogeny Control of phiCDKH01 Bacteriophage Infecting Clinical Isolate of Clostridioides difficile

Clostridioides difficile is a causative agent of antibiotic-associated diarrhea as well as pseudomembranous colitis. So far, all known bacteriophages infecting these bacteria are temperate, which means that instead of prompt lysis of host cells, they can integrate into the host genome or replicate episomally. While C. difficile phages are capable of spontaneous induction and entering the lytic pathway, very little is known about the regulation of their maintenance in the state of lysogeny. In this study, we investigated the properties of a putative major repressor of the recently characterized C. difficile phiCDKH01 bacteriophage. A candidate protein belongs to the XRE family and controls the transcription of genes encoding putative phage antirepressors, known to be involved in the regulation of lytic development. Hence, the putative major phage repressor is likely to be responsible for maintenance of the lysogeny.

Implementing antimicrobial stewardship: lessons and perspectives from a university-affiliated tertiary hospital in Korea

Antimicrobial stewardship programs (ASPs) can lower antibiotic use, decrease medical expenses, prevent the emergence of resistant bacteria, and enhance treatment for infectious diseases. This study summarizes the stepwise implementation and effects of ASPs in a single university-affiliated tertiary care hospital in Korea; it also presents future directions and challenges in resource-limited settings. At the study hospital, the core elements of the ASP such as leadership commitment, accountability, and operating system were established in 2000, then strengthened by the formation of the Antimicrobial Stewardship (AMS) Team in 2018. The actions of ASPs entail key components including a computerized restrictive antibiotic prescription system, prospective audit, post-prescription review through quantitative and qualitative intervention, and pharmacy-based interventions to optimize antibiotic usage. The AMS Team regularly tracked antibiotic use, the effects of interventions, and the resistance patterns of pathogens in the hospital. The reporting system was enhanced and standardized by participation in the Korea National Antimicrobial Use Analysis System, and educational efforts are ongoing. Stepwise implementation of the ASP and the efforts of the AMS Team have led to a substantial reduction in the overall consumption of antibiotics, particularly regarding injectables, and optimization of antibiotic use. Our experience highlights the importance of leadership, accountability, institution-specific interventions, and the AMS Team.

Postoperative Prophylactic Antibiotic Use in Breast Reduction Mammoplasty: A Single Centre Retrospective Cohort Study

Introduction: Breast reduction mammoplasty (BRM) is a common procedure performed by plastic surgeons treating patients with hypermastia. It is customary to give preoperative prophylactic intravenous antibiotics for BRM, followed by several days of postoperative prophylactic oral antibiotics, despite the lack of evidence of their effectiveness in preventing surgical site infections (SSIs). The purpose of this study is to determine if the addition of prophylactic postoperative antibiotics is more effective in preventing SSIs in comparison to a single dose of preoperative prophylactic antibiotics in BRM. Methods: A retrospective analysis of 124 elective BRM cases by a single senior plastic surgeon was completed. Two study groups were formed based on the location of surgery and each group was assigned a different antibiotic regimen. The first antibiotic regimen consisted of a single preoperative intravenous dose of antibiotics (group 1), while the second regimen consisted of a preoperative intravenous dose followed by a 5-day course of oral antibiotics (group 2). Results: Overall SSI rate was 5.6%. Infection rate in group 1 was 8.1% in comparison to 3.2% for group 2 (P value .44). Overall, the incidence of complications was 29.0%; 38.7% in group 1 and 19.4% in group 2 (P value .03). Complications consisted of 35 cases of delayed wound healing, 7 SSIs and 2 hematomas requiring evacuation. Conclusion: Study results demonstrated that the use of postoperative prophylactic antibiotics for BRM had no significant effect on the rate of SSIs.

Derivation and internal validation of the multivariate toxigenic C. difficile diarrhea model and risk score for emergency room and hospitalized patients with diarrhea

Background

Many factors have been associated with the risk of toxigenic C. difficile diarrhea (TCdD). This study derived and internally validated a multivariate model for estimating the risk of TCdD in patients with diarrhea using readily available clinical factors.

Methods

A random sample of 3,050 symptomatic emergency department or hospitalized patients undergoing testing for toxigenic C. difficile at a single teaching hospital between 2014 and 2018 was created. Unformed stool samples positive for both glutamate dehydrogenase antigen by enzyme immunoassay and tcdB gene by polymerase chain reaction were classified as TCdD positive. The TCdD Model was created using logistic regression and was modified to the TCdD Risk Score to facilitate its use.

Results

8.1% of patients were TCdD positive. TCdD risk increased with abdominal pain (adjusted odds ratio 1.3; 95% CI, 1.0-1.8), previous C. difficile diarrhea (2.5, 1.1-6.1), and prior antibiotic exposure, especially when sampled in the emergency department (4.2, 2.5-7.0) versus the hospital (1.7, 1.3-2.3). TCdD risk also increased when testing occurred earlier during the hospitalization encounter, when age and white cell count increased concurrently, and with decreased eosinophil count. In internal validation, the TCdD Model had moderate discrimination (optimism-corrected C-statistic 0.65, 0.62-0.68) and good calibration (optimism-corrected Integrated Calibration Index [ICI] 0.017, 0.001-0.022). Performance decreased slightly for the TCdD Risk Score (C-statistic 0.63, 0.62-0.63; ICI 0.038, 0.004-0.038).

Conclusions

TCdD risk can be predicted using readily available clinical risk factors with modest accuracy.

Fecal microbiota transplantation stimulates type 2 and tolerogenic immune responses in a mouse model

OBJECTIVES

Clostridioides difficile infection (CDI) is the leading hospital-acquired infection in North America. While previous work on fecal microbiota transplantation (FMT), a highly effective treatment for CDI, has focused on colonization resistance mounted against C. difficile by FMT-delivered commensals, the effects of FMT on host gene expression are relatively unexplored. This study aims to identify transcriptional changes associated with FMT, particularly changes associated with protective immune responses.

METHODS

Gene expression was assessed on day 2 and day 7 after FMT in mice after antibiotic-induced dysbiosis. Flow cytometry was also performed on colon and mesenteric lymph nodes at day 7 to investigate changes in immune cell populations.

RESULTS

FMT administration after antibiotic-induced dysbiosis successfully restored microbial alpha diversity to levels of donor mice by day 7 post-FMT. Bulk RNA sequencing of cecal tissue at day 2 identified immune genes, including both pro-inflammatory and Type 2 immune pathways as upregulated after FMT. RNA sequencing was repeated on day 7 post-FMT, and expression of these immune genes was decreased along with upregulation of genes associated with restoration of intestinal homeostasis. Immunoprofiling on day 7 identified increased colonic CD45+ immune cells that exhibited dampened Type 1 and heightened regulatory and Type 2 responses. These include an increased abundance of eosinophils, alternatively activated macrophages, Th2, and T regulatory cell populations.

CONCLUSION

These results highlight the impact of FMT on host gene expression, providing evidence that FMT restores intestinal homeostasis after antibiotic treatment and facilitates tolerogenic and Type 2 immune responses.

Investigating the impact of antibiotic-induced dysbiosis on protection from Clostridium difficile colitis by mouse colonic innate lymphoid cells

Innate lymphoid cells (ILCs) play a critical role in maintaining intestinal health in homeostatic and diseased conditions. During Clostridium difficile infection (CDI), IL-33 activates ILC2 to protect from colonic damage and mortality. The function of IL-33 and ILC is tightly regulated by the intestinal microbiota. We set out to determine the impact of antibiotic-induced disruption of the microbiome on ILC function. Our goal was to understand antibiotic-induced changes in ILC function on susceptibility to C. difficile colitis in a mouse model. We utilized high-throughput single-cell RNAseq to investigate the phenotypic features of colonic ILC at baseline, after antibiotic administration with or without IL-33 treatment. We identified a heterogeneous landscape of colonic ILCs with gene signatures of inflammatory, anti-inflammatory, migratory, progenitor, plastic, and antigen-presenting ILCs. Antibiotic treatment decreased ILC2 while coordinately increasing ILC1 and ILC3 phenotypes. Notably, Ifng+, Ccl5+, and Il23r+ ILC increased after antibiotics. IL-33 treatment counteracted the antibiotic effect by downregulating ILC1 and ILC3 and activating ILC2. In addition, IL-33 treatment markedly induced the expression of type 2 genes, including Areg and Il5. Finally, we identified amphiregulin, produced by ILC2, as protective during C. difficile infection. Together, our data expand our understanding of how antibiotics induce susceptibility to C. difficile colitis through their impact on ILC subsets and function.IMPORTANCEClostridium difficile infection (CDI) accounts for around 500,000 symptomatic cases and over 20,000 deaths annually in the United States alone. A major risk factor of CDI is antibiotic-induced dysbiosis of the gut. Microbiota-regulated IL-33 and innate lymphoid cells (ILCs) are important in determining the outcomes of C. difficile infection. Understanding how antibiotic and IL-33 treatment alter the phenotype of colon ILCs is important to identify potential therapeutics. Here, we performed single-cell RNAseq of mouse colon ILCs collected at baseline, after antibiotic treatment, and after IL-33 treatment. We identified heterogeneous subpopulations of all three ILC subtypes in the mouse colon. Our analysis revealed several potential pathways of antibiotic-mediated increased susceptibility to intestinal infection. Our discovery that Areg is abundantly expressed by ILCs, and the protection of mice from CDI by amphiregulin treatment, suggests that the amphiregulin-epidermal growth factor receptor pathway is a potential therapeutic target for treating intestinal colitis.

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.

Top 25 Medications the Plastic and Reconstructive Surgery Trainee Should Know for an Emergency Medicine Department Consult

SUMMARY

Plastic surgery trainees are often called to render care in the emergency department (eg, for established patients, trauma, burns). Broad-based knowledge in pharmacotherapeutics during these encounters is critical. This includes an understanding of pain medications, anxiolytics, local anesthetics, antibiotics, anticoagulants, antidotes, and more to ensure optimal patient care. The purpose of this report is to describe 25 frequently used and other important medications that plastic surgery trainees should know for an adult emergency department encounter.

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.

Improving Clostridioides difficile Infectious Disease Treatment Response via Adherence to Clinical Practice Guidelines

Clostridioides difficile (C. difficile) is a predominant nosocomial infection, and guidelines for improving diagnosis and treatment were published in 2017. We conducted a single-center, retrospective 10-year cohort study of patients with primary C. difficile infectious disease (CDID) at the largest referral Lithuanian university hospital, aiming to evaluate the clinical and laboratory characteristics of CDID and their association with the outcomes, as well as implication of concordance with current Clinical Practice Guidelines. The study enrolled a total of 370 patients. Cases with non-concordant CDID treatment resulted in more CDID-related Intensive Care Unit (ICU) admissions (7.5 vs. 1.8%) and higher CDID-related mortality (13.0 vs. 1.8%) as well as 30-day all-cause mortality (61.0 vs. 36.1%) and a lower 30-day survival compared with CDID cases with concordant treatment (p < 0.05). Among cases defined by two criteria for severe CDID, only patients with non-concordant metronidazole treatment had refractory CDID (68.8 vs. 0.0%) compared with concordant vancomycin treatment. In the presence of non-concordant metronidazole treatment for severe CDID, only cases defined by two severity criteria had more CDID-related ICU admissions (18.8 vs. 0.0%) and higher CDID-related mortality (25.0 vs. 2.0%, p < 0.05) compared with cases defined by one criterion. Severe comorbidities and the continuation of concomitant antibiotics administered at CDID onset reduced (p < 0.05) the 30-day survival and increased (p = 0.053) 30-day all-cause mortality, with 57.6 vs. 10.7% and 52.0 vs. 25.0%, respectively. Conclusions: CDID treatment non-concordant with the guidelines was associated with various adverse outcomes. In CDID with leukocytes ≥ 15 × 109/L and serum creatinine level > 133 µmol/L (>1.5 mg/dL), enteral vancomycin should be used to avoid refractory response, as metronidazole use was associated with CDID-related ICU admission and CDID-related mortality. Severe comorbidities worsened the outcomes as they were associated with reduced 30-day survival. The continuation of concomitant antibiotic therapy increased 30-day all-cause mortality; thus, it needs to be reasonably justified, deescalated or stopped.

Clostridioides Difficile: A Concise Review of Best Practices and Updates

Clostridioides difficile infection (CDI) is one of the most common and severe nosocomial infections worldwide. It can also affect healthy individuals in the community. The incidence of CDI has been on the rise globally for the past decade, necessitating a proactive approach to combat its spread; new strategies are being developed to enhance diagnostic accuracy and optimize treatment outcomes. Implementing the 2-step testing has increased diagnostic specificity, reducing the usage of CD-specific antibiotics with no concomitant increase in surgical complication rates. In 2021, the Infectious Diseases Society of America/Society for Healthcare Epidemiology of America (IDSA/SHEA) shifted its preference for initial treatment to fidaxomicin over vancomycin and metronidazole due to its lower recurrence rate. It also prioritized fidaxomicin for the treatment of recurrent CDI. There are new developments on the frontiers of fecal microbiota therapies, with RBX2660 and SER-109 approved recently by the FDA for prevention, with other microbiome-based therapies in various development and clinical trials. This review offers providers an updated and practical guide for CDI management.

Antibiotic Resistances of Clostridioides difficile

The rapid evolution of antibiotic resistance in Clostridioides difficile and the consequent effects on prevention and treatment of C. difficile infections (CDIs) are a matter of concern for public health. Antibiotic resistance plays an important role in driving C. difficile epidemiology. Emergence of new types is often associated with the emergence of new resistances, and most of the epidemic C. difficile clinical isolates is currently resistant to multiple antibiotics. In particular, it is to worth to note the recent identification of strains with reduced susceptibility to the first-line antibiotics for CDI treatment and/or for relapsing infections. Antibiotic resistance in C. difficile has a multifactorial nature. Acquisition of genetic elements and alterations of the antibiotic target sites, as well as other factors, such as variations in the metabolic pathways or biofilm production, contribute to the survival of this pathogen in the presence of antibiotics. Different transfer mechanisms facilitate the spread of mobile elements among C. difficile strains and between C. difficile and other species. Furthermore, data indicate that both genetic elements and alterations in the antibiotic targets can be maintained in C. difficile regardless of the burden imposed on fitness, and therefore resistances may persist in C. difficile population in absence of antibiotic selective pressure.

Clostridioides difficile infection after extracorporeal membrane oxygenation support for acute myocardial infarction: a case report

Introduction

Restored cardiopulmonary function is efficiently achieved by utilizing extracorporeal membrane oxygenation (ECMO). Nevertheless, the incidence of Clostridioides difficile infection (CDI) associated with ECMO is relatively uncommon.

Case presentation

In this report, we present the case of a 59-year-old male with severe chest pain due to acute myocardial infarction, subsequently necessitating ECMO support. During the first day of hospitalization, pulmonary infections were observed, and piperacillin-tazobactam was prescribed for 7 days at low dosages. However, the patient developed severe diarrhea 4 days later. After ruling out common pathogens, we suspected the occurrence of CDI and performed genetic testing for C. difficile toxin, confirming our diagnosis. The prescription of vancomycin resulted in slight improvement, while fecal microbiota transplantation (FMT) proved to be more effective.

Conclusion

In this case, temporary application of ECMO was applied, and the anti-infective treatment relied on the use of antibiotics at short-term, low-dose, and low CDI risk. Hence, the occurrence of CDI was considered an uncommon event, which may serve as a reference for future cases.

Ethics of antibiotic allergy

Antibiotic allergies are commonly reported among patients, but most do not experience reactions on rechallenge with the same agents. These reported allergies complicate management of infections in patients labelled as having penicillin allergy, including serious infections where penicillin-based antibiotics are the first-line (most effective and least toxic) treatment option. Allergy labels are rarely questioned in clinical practice, with many clinicians opting for inferior second-line antibiotics to avoid a perceived risk of allergy. Reported allergies thereby can have significant impacts on patients and public health, and present major ethical challenges. Antibiotic allergy testing has been described as a strategy to circumvent this dilemma, but it carries limitations that often make it less feasible in patients with acute infections or in community settings that lack access to allergy testing. This article provides an empirically informed ethical analysis of key considerations in this clinical dilemma, using Staphylococcus aureus bacteraemia in patients with penicillin allergies as a case study. We argue that prescribing first-line penicillin-based antibiotics to patients with reported allergies may often present a more favourable ratio of benefits to risks, and may therefore be more ethically appropriate than using second-line drugs. We recommend changes to policy-making, clinical research and medical education, in order to promote more ethically acceptable responses to antibiotic allergies than the status quo.

Implementation strategies for hospital-based probiotic administration in a stepped-wedge cluster randomized trial design for preventing hospital-acquired Clostridioides difficile infection

BACKGROUND

Clostridioides difficile infection (CDI) is associated with considerable morbidity and mortality in hospitalized patients, especially among older adults. Probiotics have been evaluated to prevent hospital-acquired (HA) CDI in patients who are receiving systemic antibiotics, but the implementation of timely probiotic administration remains a challenge. We evaluated methods for effective probiotic implementation across a large health region as part of a study to assess the real-world effectiveness of a probiotic to prevent HA-CDI (Prevent CDI-55 +).

METHODS

We used a stepped-wedge cluster-randomized controlled trial across four acute-care adult hospitals (n = 2,490 beds) to implement the use of the probiotic Bio-K + ® (Lactobacillus acidophilus CL1285®, L. casei LBC80R® and L. rhamnosus CLR2®; Laval, Quebec, Canada) in patients 55 years and older receiving systemic antimicrobials. The multifaceted probiotic implementation strategy included electronic clinical decision support, local site champions, and both health care provider and patient educational interventions. Focus groups were conducted during study implementation to identify ongoing barriers and facilitators to probiotic implementation, guiding needed adaptations of the implementation strategy. Focus groups were thematically analyzed using the Theoretical Domains Framework and the Consolidated Framework of Implementation Research.

RESULTS

A total of 340 education sessions with over 1,800 key partners and participants occurred before and during implementation in each of the four hospitals. Site champions were identified for each included hospital, and both electronic clinical decision support and printed educational resources were available to health care providers and patients. A total of 15 individuals participated in 2 focus group and 7 interviews. Key barriers identified from the focus groups resulted in adaptation of the electronic clinical decision support and the addition of nursing education related to probiotic administration. As a result of modifying implementation strategies for identified behaviour change barriers, probiotic adherence rates were from 66.7 to 75.8% at 72 h of starting antibiotic therapy across the four participating acute care hospitals.

CONCLUSIONS

Use of a barrier-targeted multifaceted approach, including electronic clinical decision support, education, focus groups to guide the adaptation of the implementation plan, and local site champions, resulted in a high probiotic adherence rate in the Prevent CDI-55 + study.

Antibiotics and antibiotic-associated diarrhea: a real-world disproportionality study of the FDA adverse event reporting system from 2004 to 2022

BACKGROUND

Our study aimed to assess the risk signals of antibiotic-associated diarrhea (AAD) caused by various antibiotics using real-world data and provide references for safe clinical applications.

METHODS

We analyzed data extracted from the FDA Adverse Event Reporting System (FAERS) database, covering the period from the first quarter of 2004 to the third quarter of 2022. We computed the reporting odds ratio (ROR) for each antibiotic or antibiotic class to compare the signal difference. Furthermore, we also examined the differences in the onset times and outcomes of AAD caused by various antibiotics.

RESULTS

A total of 5,397 reports met the inclusion requirements. Almost all antibiotics, except tobramycin and minocycline (ROR 0.98; 95%CI: 0.64-1.51 and 0.42; 95%CI: 0.16-1.11, respectively), showed a significant correlation with AAD. The analysis of the correlation between different classes of antibiotics and AAD revealed that lincomycins (ROR 29.19; 95%CI: 27.06-31.50), third-generation cephalosporins (ROR 15.96; 95%CI: 14.58-17.47), and first/second generation cephalosporins (ROR 15.29; 95%CI: 13.74-17.01) ranked the top three. The ROR values for antibiotics from the same class of antibiotics also varied greatly, with the ROR values for third-generation cephalosporins ranging from 9.97 to 58.59. There were also differences in ROR values between β-lactamase inhibitors and their corresponding β-lactamase drugs, such as amoxicillin-clavulanate (ROR = 13.31; 95%CI: 12.09-14.65) and amoxicillin (ROR = 6.50; 95%CI: 5.69-7.44). 91.35% of antibiotics have an onset time of less than four weeks.

CONCLUSIONS

There is a significant correlation between almost all antibiotics and AAD, particularly lincomycins and β-lactam antibiotics, as well as a different correlation within the same class. These findings offer valuable evidence for selecting antibiotics appropriately.

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.

Impact of the COVID-19 pandemic on Clostridioides difficile infection in a tertiary healthcare institution in Belgium

OBJECTIVES

Clostridioides difficile infection (CDI) causes the greatest number of healthcare-associated infectious diarrhoea. CDIs are transmitted by direct and indirect patient-to-patient contact and risk increases with the use of antibiotics. Since early 2020, the COVID-19 pandemic has affected healthcare systems in many ways including substantial changes in hygiene behaviour. The aim of this study was to assess whether CDI incidence differed during the COVID-19 pandemic compared to a year before.

METHODS

All tests for suspected CDI cases were recorded for a hospital in Brussels, Belgium. The percentage of CDI-positive results and incidences (total and healthcare-associated (HA)-CDI)) for years 2019, 2020, 2021, and 2022 were calculated. Antibiotic consumption was analysed for years 2019 and 2020.

RESULTS

Since the COVID-19 pandemic struck, a significant reduction of up to 39% was observed in the number of Clostridioides difficile stool tests in our hospital. A significant decrease in the percentage of positive tests and a 50% decrease in the incidence of CDI (total and HA-CDI) was found for 2020 compared with 2019 and confirmed for years 2021 and 2022. The decrease in CDI incidence was mostly marked in haematology, nephrology, and gastroenterology units. No significant change in the use of antibiotics was found.

CONCLUSION

The global decrease in CDI incidence observed in our hospital was not associated with a change in the use of antibiotics. The control measures implemented to prevent COVID-19 transmission may explain a reduction in CDI incidence. An underdiagnosis of CDI cannot be excluded.

Clostridioides difficile MreE (PBP2) variants facilitate clinical disease during cephalosporin exposures

Cephalosporins are the most common triggers of healthcare-associated Clostridioides difficile infections (CDI). Here, we confirm gene-level drivers of cephalosporin resistance and their roles in promoting disease. Genomic-epidemiologic analyses of 306 C. difficile isolates from a hospital surveillance program monitoring asymptomatic carriers and CDI patients identified prevalent third-generation cephalosporin resistance to ceftriaxone at >256 ug/mL in 26% of isolates. Resistance was associated with patient cephalosporin exposures 8-10 days before C. difficile detection. Genomic analyses identified variants in the mreE penicillin binding protein 2 (PBP2) associated with resistance to multiple beta-lactam classes. Transfer of variants into susceptible strain CD630 elevated resistance to first and third-generation cephalosporins. Transfer into the mouse-infective strain ATCC 43255 enabled disease when mice were exposed to 500ug/mL cefoperazone, a dose that inhibited the isogenic susceptible strain. Our findings establish roles of cephalosporins and mreE-cephalosporin-resistant variants in CDI and provide testable genetic loci for detecting resistance in patient strains.

Clostridium difficile colitis following geriatric hip fracture surgery: incidence, trends, and risk factors from 45,910 patients

PURPOSE

Clostridium difficile colitis is a serious complication in elderly patients undergoing surgery. The objectives of this study were: (1) to use a nationwide sample of patients to report the incidence and timing of C. difficile colitis in geriatric patients who underwent surgery for hip fractures, (2) to identify preoperative factors associated with developing C. difficile colitis and mortality.

METHODS

This was a retrospective evaluation of the 2016-2019 ACS Targeted Hip Fracture database merged with the ACS-NSQIP database. Patients undergoing surgery for hip fracture were included. Outcomes studied were incidence, preoperative, and postoperative risk factors for occurrence of C. difficile infection and mortality. Chi-squared tests were used to compare demographics between the patients infected (study) and not infected (control). Logistic regression models were utilized to compute the odds ratios (OR) testing for the association of independent factors on developing C. difficile infection postoperatively and mortality. A statistical threshold was set at p < 0.008.

RESULTS

The incidence of C. difficile infection within 30 days of hip fracture surgery was 0.81%. Fifty percent of infections were diagnosed within 9 days postoperatively. Preoperative and hospital-associated factors associated with development of C. difficile infection were ≥ 2 days until operation (OR 1.88 [95% CI 1.39-2.55], p < 0.001) and dependent functional status (OR 1.43 [95% CI 1.14-1.79], p = 0.002). After adjusting for multiple comorbidities, increased age, male sex, COPD, CHF, dependent functional status, and C. difficile infection were associated with increased mortality within 30 days of surgery (all p < 0.001).

CONCLUSION

Clostridium difficile colitis is a serious infection after hip fracture surgery in geriatric patients with an incidence of about 1%. Patients at increased risk should be targeted with preventative measures to prevent the morbidity from this complication.

Design of 8-mer peptides that block Clostridioides difficile toxin A in intestinal cells

Infections by Clostridioides difficile, a bacterium that targets the large intestine (colon), impact a large number of people worldwide. Bacterial colonization is mediated by two exotoxins: toxins A and B. Short peptides that can be delivered to the gut and inhibit the biocatalytic activity of these toxins represent a promising therapeutic strategy to prevent and treat C. diff. infection. We describe an approach that combines a Peptide Binding Design (PepBD) algorithm, molecular-level simulations, a rapid screening assay to evaluate peptide:toxin binding, a primary human cell-based assay, and surface plasmon resonance (SPR) measurements to develop peptide inhibitors that block Toxin A in colon epithelial cells. One peptide, SA1, is found to block TcdA toxicity in primary-derived human colon (large intestinal) epithelial cells. SA1 binds TcdA with a KD of 56.1 ± 29.8 nM as measured by surface plasmon resonance (SPR).

Comparison of Different Antibiotics and the Risk for Community-Associated Clostridioides difficile Infection: A Case-Control Study

Background

Antibiotics are the greatest risk factor for Clostridioides difficile infection (CDI). Risk for CDI varies across antibiotic types and classes. Optimal prescribing and stewardship recommendations require comparisons of risk across antibiotics. However, many prior studies rely on aggregated antibiotic categories or are underpowered to detect significant differences across antibiotic types. Using a large database of real-world data, we evaluate community-associated CDI risk across individual antibiotic types.

Methods

We conducted a matched case-control study using a large database of insurance claims capturing longitudinal health care encounters and medications. Case patients with community-associated CDI were matched to 5 control patients by age, sex, and enrollment period. Antibiotics prescribed within 30 days before the CDI diagnosis along with other risk factors, including comorbidities, health care exposures, and gastric acid suppression were considered. Conditional logistic regression and a Bayesian analysis were used to compare risk across individual antibiotics. A sensitivity analysis of antibiotic exposure windows between 30 and 180 days was conducted.

Results

We identified 159 404 cases and 797 020 controls. Antibiotics with the greatest risk for CDI included clindamycin and later-generation cephalosporins, and those with the lowest risk included minocycline and doxycycline. We were able to differentiate and order individual antibiotics in terms of their relative level of associated risk for CDI. Risk estimates varied considerably with different exposure windows considered.

Conclusions

We found wide variation in CDI risk within and between classes of antibiotics. These findings ordering the level of associated risk across antibiotics can help inform tradeoffs in antibiotic prescribing decisions and stewardship efforts.

Effects of procalcitonin on antimicrobial treatment decisions in patients with coronavirus disease 2019 (COVID-19)

OBJECTIVE

To describe the natural course of procalcitonin (PCT) in patients with coronavirus disease 2019 (COVID-19) and the correlation between PCT and antimicrobial prescribing to provide insight into best practices for PCT data utilization in antimicrobial stewardship in this population.

DESIGN

Single-center, retrospective, observational study.

SETTING

Michigan Medicine.

PATIENTS

Inpatients aged ≥18 years hospitalized March 1, 2020, through October 31, 2021, who were positive for severe acute respiratory coronavirus virus 2 (SARS-CoV-2), with ≥1 PCT measurement. Exclusion criteria included antibiotics for nonpulmonary bacterial infection on admission, treatment with azithromycin only for chronic obstructive pulmonary disease (COPD) exacerbation, and pre-existing diagnosis of cystic fibrosis with positive respiratory cultures.

METHODS

A structured query was used to extract data. For patients started on antibiotics, bacterial pneumonia (bPNA) was determined through chart review. Multivariable models were used to assess associations of PCT level and bPNA with antimicrobial use.

RESULTS

Of 793 patients, 224 (28.2%) were initiated on antibiotics: 33 (14.7%) had proven or probable bPNA, 125 (55.8%) had possible bPNA, and 66 (29.5%) had no bPNA. Patients had a mean of 4.1 (SD, ±5.2) PCT measurements if receiving antibiotics versus a mean of 2.0 (SD, ±2.6) if not. Initial PCT level was highest for those with proven/probable bPNA and was associated with antibiotic initiation (odds ratio 95% confidence interval [CI], 1.17-1.30). Initial PCT (rate ratio [RR] 95% CI, 1.01-1.08), change in PCT over time (RR 95% CI, 1.01-1.05), and bPNA group (RR 95% CI, 1.23-1.84) were associated with antibiotic duration.

CONCLUSIONS

PCT trends are associated with the decision to initiate antibiotics and duration of treatment, independent of bPNA status and comorbidities. Prospective studies are needed to determine whether PCT level can be used to safely make decisions regarding antibiotic treatment for COVID-19.

Evaluation of Antibiotic Prescribing Pattern Using WHO Access, Watch and Reserve Classification in Kinshasa, Democratic Republic of Congo

BACKGROUND

The AWaRe tool was set up by the World Health Organization (WHO) to promote the rational use of antimicrobials. Indeed, this tool classifies antibiotics into four groups: access, watch, reserve and not-recommended antibiotics. In The Democratic Republic of Congo, data on antibiotic dispensing (prescribing) by health professionals according to the AWaRe classification are scarce. In this research work, we aimed to explore antibiotic dispensing pattern from health professionals according to the WHO AWaRe classification to strengthen the national antimicrobial resistance plan.

METHODS

For this purpose, a survey was conducted from July to December 2022 in the district of Tshangu in Kinshasa. From randomly selected drugstores, drug-sellers were interviewed and randomly selected customers attending those drugstores were included in the study for medical prescriptions collection. The prescribed antibiotics were classified into the access, watch, reserve and not-recommended antibiotics group and by antibiotics number by prescription among pharmacies surveyed.

RESULTS

400 medical prescriptions were collected from 80 drugstores and among which, 301 (75.25%) contained antibiotics. Out of 301 prescriptions, we noticed 164 (54.5%) containing one antibiotic, 117 (38.9%) containing two antibiotics, 15 (5%) containing three antibiotics and 5 (1.6%) containing four antibiotics. A total of 463 antibiotics were prescribed and distributed as 169 (36.5%) were from the access group, 200 (43.2%) from the watch group and 94 (20.3%) from not-recommended antibiotics group, respectively. This can explain the fact of emerging bacterial strains, as, according to the WHO recommendations, the access group should be prioritized because of its activity against a wide range of commonly encountered pathogens and its showing low resistance susceptibility compared to antibiotics from other groups. Based on the anatomical, therapeutic and chemical (ATC) classifications, we observed that third generation cephalosporins represented 34.33% of the prescribed antibiotics, followed by penicillins (17.17%), macrolides (7.63%), aminoglycosides (7.36%) and Imidazole (7.36%), thus accounting approximately for 74% of the classes of antibiotics prescribed. Additionally, among them, the most frequently prescribed antibiotics were Ceftriaxone (21.38%), Amoxicillin (11.01%), Gentamycin (5.61%), Amoxicillin-clavulanic acid (5.61%), Azithromycin (4.97%) and Metronidazole (4.75%), thus accounting for approximately 54% of all the prescribed antibiotics.

CONCLUSION

These results highlight the importance of strict implementation of the national plan to combat antimicrobial resistance and the need to train health workers in the correct application of the WHO AWaRe classification.

Antimicrobial susceptibility of Clostridioides difficile to omadacycline and comparator antimicrobials

BACKGROUND

Omadacycline is a novel aminomethylcycline tetracycline antimicrobial that was approved for the treatment of community-associated bacterial pneumonia (CABP) and acute bacterial skin and skin structure infections (ABSSSI) in 2018. Omadacycline has demonstrated a high degree of in vitro activity towards Clostridioides difficile and previous data have hypothesized that use of omadacycline for CABP or ABSSSI may decrease the risk of C. difficile infections.

OBJECTIVES

To compare the in vitro antimicrobial activity of omadacycline versus commonly used antimicrobials for the approved indications of use.

METHODS

We compared the antimicrobial activity of eight antimicrobials approved for CABP and ABSSSI against omadacycline by agar dilution on 200 clinically relevant contemporary C. difficile isolates representing local and national prevalent strain types.

RESULTS

The in vitro omadacycline geometric mean MIC was 0.07 mg/L. Ceftriaxone resistance was noted in >50% of all isolates tested. The epidemic strain group, identified as restriction endonuclease analysis (REA) group BI, was commonly resistant to azithromycin (92%), moxifloxacin (86%) and clindamycin (78%). REA group DH strains had an elevated trimethoprim/sulfamethoxazole geometric mean MIC of 17.30 mg/L compared with the geometric mean MIC of 8.14 mg/L noted in all other isolates. In the REA group BK isolates that had a doxycycline MIC of ≥2 mg/L, the omadacycline MIC was <0.5 mg/L.

CONCLUSIONS

Among 200 contemporary C. difficile isolates, there were no notable elevations in the in vitro omadacycline MIC, indicating a high level of activity towards C. difficile in comparison with commonly used antimicrobials for CABP and ABSSSI.

Identification of antibiotic consumption targets for the management of Clostridioides difficile infection in hospitals- a threshold logistic modelling approach

BACKGROUND

This study aims to demonstrate the utility of a threshold logistic approach to identifying thresholds for specific antibiotic use associated with Clostridioides difficile infection (CDI) in an English teaching hospital.

METHODS

A combined approach of nonlinear modeling and logistic regression, named threshold logistic, was used to identify thresholds and risk scores in hospital-level antibiotic use associated with hospital-onset, healthcare-associated (HOHA) CDI cases.

RESULTS

Using a threshold logistic regression approach, an incidence greater than 0.2645 cases/1000 occupied bed-days (OBD; 85th percentile) was determined as the cutoff rate to define a critical (high) incidence rate of HOHA CDI. Fluoroquinolones and piperacillin-tazobactam were found to have thresholds at 84.8 and 54 defined daily doses (DDD)/1000 OBD, respectively. Analysis of data allowed calculating risk scores for HOHA CDI incidence rates exceeding the 85th percentile, i.e. entering critical incidence level. The threshold-logistic model also facilitated performing 'what-if scenarios' on future values of fluoroquinolones and piperacillin-tazobactam use to understand how HOHA CDI incidence rates may be affected.

CONCLUSION

Using threshold logistic analysis, critical incidence levels and antibiotic use targets to control HOHA CDI were determined. Threshold logistic models can be used to inform and enhance the effective design and implementation of antimicrobial stewardship programs.

Clostridioides difficile infection in infants: a case report and literature review

BACKGROUND

Clostridioides difficile (C. difficile) is the major pathogen causing antibiotic-associated diarrhea. There are a variety of symptoms associated with C. difficile infection (CDI) in adults, including self-limiting diarrhea, pseudomembranous colitis, toxic megacolon, septic shock, and even death from the infection. However, the infant's intestine appears to be completely resistant to the effects of C. difficile toxins A and B with rare development of clinical symptoms.

CASE PRESENTATION

In this study, we reported a 1-month-old girl with CDI who was born with neonatal hypoglycemia and necrotizing enterocolitis. Her symptom of diarrhea occurred after extensive use of broad-spectrum antibiotics during hospitalization and was accompanied by elevated white blood cell, platelet, and C-reactive protein levels, and repeated routine stool examinations were abnormal. She was recovered by norvancomycin (an analogue of vancomycin) and probiotic treatment. The results of 16 S rRNA gene sequencing also demonstrated the recovery of intestinal microbiota with the enrichment of Firmicutes and Lactobacillus.

CONCLUSIONS

Based on the literature review and this case report, clinicians should also pay attention to diarrhea caused by C. difficile in infants and young children. More strong evidence is needed to explain the true prevalence of CDI in this population and to better understand the C. difficile-associated diarrhea in infants.

Real-World Data in Pharmacovigilance Database Provides a New Perspective for Understanding the Risk of Clostridium difficile Infection Associated with Antibacterial Drug Exposure

Antibacterial drug exposure (ADE) is a well-known potential risk factor for Clostridium difficile infection (CDI), but it remains controversial which certain antibacterial drugs are associated with the highest risk of CDI occurrence. To summarize CDI risk associated with ADE, we reviewed the CDI reports related to ADE in the FDA Adverse Event Reporting System database and conducted disproportionality analysis to detect adverse reaction (ADR) signals of CDI for antibacterial drugs. A total of 8063 CDI reports associated with ADE were identified, which involved 73 antibacterial drugs. Metronidazole was the drug with the greatest number of reports, followed by vancomycin, ciprofloxacin, clindamycin and amoxicillin. In disproportionality analysis, metronidazole had the highest positive ADR signal strength, followed by vancomycin, cefpodoxime, ertapenem and clindamycin. Among the 73 antibacterial drugs, 58 showed at least one positive ADR signal, and ceftriaxone was the drug with the highest total number of positive signals. Our study provided a real-world overview of CDI risk for AED from a pharmacovigilance perspective and showed risk characteristics for different antibacterial drugs by integrating its positive-negative signal distribution. Meanwhile, our study showed that the CDI risk of metronidazole and vancomycin may be underestimated, and it deserves further attention and investigation.

A pilot study of dietary fibres on pathogen growth in an ex vivo colonic model reveals their potential ability to limit vancomycin-resistant Enterococcus expansion

Aim: Dietary fibre is important for shaping gut microbiota. The aim of this pilot study was to investigate the impact of dietary fibres on pathogen performance in the presence of gut microbiota. Methods: In an ex vivo gut model, pooled faecal samples were spiked with a cocktail of representative gastrointestinal pathogens and fermented with yeast β-glucan for 24 hours, after which 16S rRNA amplicon sequencing and short-chain and branched-chain fatty acid (SCFA and BCFA) analyses were performed. In addition, oat β-glucan, arabinoxylan, yeast β-glucan, and galactooligosaccharides were each tested against individual representative pathogens and pathogen growth was assessed via qPCR. Glucose served as a control carbon source. Results: Based on 16S rRNA amplicon sequencing, yeast β-glucan selected for higher proportions of Bacteroides (P = 0.0005, ~6 fold) and Clostridia (P = 0.005, ~3.6 fold) while species of Escherichia/Shigella (P = 0.021, ~2.8 fold) and Lactobacillus (P = 0.007, ~ 15.7-fold) were higher in glucose. Pathogen relative abundance did not differ between glucose and yeast β-glucan. In the absence of pathogens, higher production of BCFAs (P = 0.002) and SCFAs (P = 0.002) fatty acids was observed for fibre group(s). For individual pathogens, yeast β-glucan increased growth of Escherichia coli, Salmonella typhimurium, and Listeria monocytogenes (P < 0.05), arabinoxylan increased S. typhimurium (P < 0.05). Tested fibres decreased vancomycin-resistant Enterococcus faecium (P < 0.05), with yeast β-glucan causing a 1-log reduction (P < 0.01), while galactooligosaccharides decreased L. monocytogenes (P < 0.05). Conclusion: Tested fibres differentially influenced the growth of pathogens, but yeast β-glucan could represent a dietary strategy to help limit vancomycin-resistant enterococci (VRE) expansion in the gut.

Assessing clinical cure of empirical piperacillin/tazobactam for ESBL urinary tract infections (ACCEPT-UTI)

Background

Data are limited regarding use of piperacillin/tazobactam for ESBL urinary tract infections (UTIs). The objective of this study was to compare clinical outcomes of patients treated empirically with piperacillin/tazobactam versus carbapenems for ESBL UTIs.

Methods

This retrospective, observational, propensity score-matched study evaluated adults with an ESBL on urine culture. Patients who had UTI symptoms or leukocytosis, and who received a carbapenem or piperacillin/tazobactam empirically for at least 48 h were included. The primary outcome was clinical success within 48 h, defined as resolution of temperature (36-38°C), resolution of symptoms or leukocytosis (WBC <12 × 10³/μL) in the absence of documented symptoms, and the absence of readmission for an ESBL UTI within 6 months. Secondary outcomes included time to clinical resolution, hospital length of stay, and in-hospital and 30 day all-cause mortality.

Results

Overall, 223 patients were included in the full cohort and 200 patients in the matched cohort (piperacillin/tazobactam = 100, carbapenem = 100). Baseline characteristics were similar between the groups. There was no difference in the primary outcome of clinical success between the carbapenem and piperacillin/tazobactam groups (58% versus 56%, respectively; P = 0.76). Additionally, there was no difference in median (IQR) time to clinical resolution [38.9 h (21.5, 50.9 h) versus 40.3 h (27.4, 57.5 h); P = 0.37], in-hospital all-cause mortality (3% versus 3%; P = 1.00), or 30 day all-cause mortality (4% versus 2%; P = 0.68) between the carbapenem and piperacillin/tazobactam groups, respectively.

Conclusions

There was no significant difference in clinical success for patients treated empirically with piperacillin/tazobactam compared with carbapenems for ESBL UTIs.

Effect of appropriate empirical antimicrobial therapy on mortality of patients with Gram-negative bloodstream infections: a retrospective cohort study

BACKGROUND

Little evidence exists regarding the prevalence of pathogens in bloodstream infections (BSIs), the mortality risk, and the benefit of combination therapy over monotherapy. This study aims to describe patterns of empiric antimicrobial therapy, and the epidemiology of Gram-negative pathogens, and to investigate the effect of appropriate therapy and appropriate combination therapy on the mortality of patients with BSIs.

METHODS

This was a retrospective cohort study including all patients with BSIs of Gram-negative pathogens from January 2017 to December 2022 in a Chinese general hospital. The in-hospital mortality was compared between appropriate and inappropriate therapy, and between monotherapy and combination therapy for patients receiving appropriate therapy. We used Cox regression analysis to identify factors independently associated with in-hospital mortality.

RESULTS

We included 205 patients in the study, of whom 147 (71.71%) patients received appropriate therapy compared with 58 (28.29%) who received inappropriate therapy. The most common Gram-negative pathogen was Escherichia coli (37.56%). 131 (63.90%) patients received monotherapy and 74 (36.10%) patients received combination therapy. The in-hospital mortality was significantly lower in patients administered appropriate therapy than inappropriate therapy (16.33% vs. 48.28%, p = 0.004); adjusted hazard ratio [HR] 0.55 [95% CI 0.35-0.84], p = 0.006). In-hospital mortality was also not different in combination therapy and monotherapy in the multivariate Cox regression analyses (adjusted HR 0.42 [95% CI 0.15-1.17], p = 0.096). However, combination therapy was associated with lower mortality than monotherapy in patients with sepsis or septic shock (adjusted HR 0.94 [95% CI 0.86-1.02], p = 0.047).

CONCLUSIONS

Appropriate therapy was associated with a protective effect on mortality among patients with BSIs due to Gram-negative pathogens. Combination therapy was associated with improved survival in patients with sepsis or septic shock. Clinicians need to choose optical empirical antimicrobials to improve survival outcomes in patients with BSIs.

Risk factors for recurrent healthcare-facility associated Clostridioides difficile infection in a Swedish setting

PURPOSE

The objectives were to determine the risk factors for recurrent healthcare facility-associated Clostridioides difficile infection (HCF-CDI) in a high CDI incidence, low antibiotic use setting and to determine if length of cefotaxime exposure is a risk factor for recurrent HCF-CDI.

METHODS

The risk factors for recurrent HCF-CDI were evaluated with a retrospective nested case control study based on chart reading. The risk factors were evaluated univariately and multivariately. Length of risk antibiotic exposure was evaluated further in a subanalysis.

RESULTS

Risk factors for recurrent HCF-CDI were renal insufficiency (25.4% of cases compared to 15.4% of controls p = 0.006) and metronidazole treatment of initial CDI episode (88.4% compared to 71.7% p = 0.01). Exposure to cefotaxime and risk for recurrent CDI showed a dose-dependent relationship (linear by linear p = 0.028).

CONCLUSIONS

Renal insufficiency and metronidazole treatment were independent risk factors for recurrent HCF-CDI in our setting. The relationship between cefotaxime exposure and risk for recurrent HCF-CDI, dose-dependent, could be evaluated further in a setting with high cefotaxime use.

Impact of an Antimicrobial Stewardship Strategy on Surgical Hospital Discharge: Improving Antibiotic Prescription in the Transition of Care

Antimicrobial stewardship programs (AMSPs) are essential elements in reducing the unnecessary overprescription of antibiotics. Most of the actions of these programs have focused on actions during acute hospitalization. However, most prescriptions occur after hospital discharge, which represents a necessary and real opportunity for improvement in these programs. We present an AMSP multifaceted strategy implemented in a surgical department which was carried out by a multidisciplinary team to verify its reliability and effectiveness. Over a 1-year post-implementation period, compared to the pre-intervention period, a significant reduction of around 60% in antibiotic exposure occurred, with lower economic cost and greater safety.

Exploring choices of early nutritional support for patients with sepsis based on changes in intestinal microecology

BACKGROUND

Sepsis exacerbates intestinal microecological disorders leading to poor prognosis. Proper modalities of nutritional support can improve nutrition, immunity, and intestinal microecology.

AIM

To identify the optimal modality of early nutritional support for patients with sepsis from the perspective of intestinal microecology.

METHODS

Thirty patients with sepsis admitted to the intensive care unit of the General Hospital of Ningxia Medical University, China, between 2019 and 2021 with indications for nutritional support, were randomly assigned to one of three different modalities of nutritional support for a total of 5 d: Total enteral nutrition (TEN group), total parenteral nutrition (TPN group), and supplemental parenteral nutrition (SPN group). Blood and stool specimens were collected before and after nutritional support, and changes in gut microbiota, short-chain fatty acids (SCFAs), and immune and nutritional indicators were detected and compared among the three groups.

RESULTS

In comparison with before nutritional support, the three groups after nutritional support presented: (1) Differences in the gut bacteria (Enterococcus increased in the TEN group, Campylobacter decreased in the TPN group, and Dialister decreased in the SPN group; all P < 0.05); (2) different trends in SCFAs (the TEN group showed improvement except for Caproic acid, the TPN group showed improvement only for acetic and propionic acid, and the SPN group showed a decreasing trend); (3) significant improvement of the nutritional and immunological indicators in the TEN and SPN groups, while only immunoglobulin G improved in the TPN group (all P < 0.05); and (4) a significant correlation was found between the gut bacteria, SCFAs, and nutritional and immunological indicators (all P < 0.05).

CONCLUSION

TEN is recommended as the preferred mode of early nutritional support in sepsis based on clinical nutritional and immunological indicators, as well as changes in intestinal microecology.

Empirical use of temocillin in hospitalized patients: results from a retrospective audit

Background

Following a global shortage of piperacillin/tazobactam in 2017, a formulary decision was taken at a large District General Hospital in the East of England to partly replace piperacillin/tazobactam with either temocillin as monotherapy or as part of a combination regimen. A retrospective audit was then conducted to assess the clinical effectiveness of temocillin therapy.

Methods

Data from patients admitted to Watford General Hospital between May and August 2017 and treated with temocillin were reviewed retrospectively. Clinical characteristics of patients, data related to the episode of infection, clinical success, tolerance and mortality were analysed.

Results

Temocillin was used in 126 patients with median age of 73 years. Infection episodes mostly originated from the abdomen (n = 46), the lung (n = 40) and the urinary tract (n = 21). Seventy-seven patients received temocillin as first-line therapy and 106 received it empirically, with temocillin prescribed in combination with another antibiotic in 82% of the empirically treated cases. Clinical success was observed in 88.9% of cases with no difference between patients treated empirically and others (89.6% versus 85%) or in efficacy among abdominal (91%), pulmonary (87.5%) and urinary (81%) infections. One case of Clostridioides difficile infection was reported in a patient treated with four different antibiotics. During the shortage period, the hospital's standardized mortality ratio was significantly lower when compared with the same period of the preceding year (85 versus 96).

Conclusions

Using temocillin as part of an empirical strategy is feasible and safe as long as appropriate antibiotic combination is recommended based upon the indication and the likely bacterial pathogen.

Bile salt hydrolases shape the bile acid landscape and restrict Clostridioides difficile growth in the murine gut

Bile acids (BAs) mediate the crosstalk between human and microbial cells and influence diseases including Clostridioides difficile infection (CDI). While bile salt hydrolases (BSHs) shape the BA pool by deconjugating conjugated BAs, the basis for their substrate selectivity and impact on C. difficile remain elusive. Here we survey the diversity of BSHs in the gut commensals Lactobacillaceae, which are commonly used as probiotics, and other members of the human gut microbiome. We structurally pinpoint a loop that predicts BSH preferences for either glycine or taurine substrates. BSHs with varying specificities were shown to restrict C. difficile spore germination and growth in vitro and colonization in pre-clinical in vivo models of CDI. Furthermore, BSHs reshape the pool of microbial conjugated bile acids (MCBAs) in the murine gut, and these MCBAs can further restrict C. difficile virulence in vitro. The recognition of conjugated BAs by BSHs defines the resulting BA pool, including the expansive MCBAs. This work provides insights into the structural basis of BSH mechanisms that shape the BA landscape and promote colonization resistance against C. difficile.

The Environment, Farm Animals and Foods as Sources of Clostridioides difficile Infection in Humans

The recent discovery of the same Clostridioides difficile ribotypes associated with human infection in a broad range of environments, animals and foods, coupled with an ever-increasing rate of community-acquired infections, suggests this pathogen may be foodborne. The objective of this review was to examine the evidence supporting this hypothesis. A review of the literature found that forty-three different ribotypes, including six hypervirulent strains, have been detected in meat and vegetable food products, all of which carry the genes encoding pathogenesis. Of these, nine ribotypes (002, 003, 012, 014, 027, 029, 070, 078 and 126) have been isolated from patients with confirmed community-associated C. difficile infection (CDI). A meta-analysis of this data suggested there is a higher risk of exposure to all ribotypes when consuming shellfish or pork, with the latter being the main foodborne route for ribotypes 027 and 078, the hypervirulent strains that cause most human illnesses. Managing the risk of foodborne CDI is difficult as there are multiple routes of transmission from the farming and processing environment to humans. Moreover, the endospores are resistant to most physical and chemical treatments. The most effective current strategy is, therefore, to limit the use of broad-spectrum antibiotics while advising potentially vulnerable patients to avoid high-risk foods such as shellfish and pork.

Impact of the cefazolin shortage on the selection and cost of parenteral antibiotics during the supply disruption period in Japan: A controlled interrupted time series analysis

BACKGROUND

A serious shortage of cefazolin (CEZ) occurred in Japan in 2019. We compared the impact of the CEZ shortage on the selection of parenteral antibiotics at affected and non-affected hospitals.

METHODS

The data were extracted from a nationwide Japanese administrative database and included all hospitalized cases between April 2016 and December 2020. We defined 'hospitals with shortage' as those hospitals with a statistically significant decrease in the use of CEZ during the supply disruption period compared to the same months of the previous year; other hospitals as 'hospitals without shortage'. We determined the proportion of each selected parenteral antibiotic use to the sum of all selected antibiotic use in the two groups of hospitals during the supply disruption period and during the same months of the previous year. A controlled interrupted time series (CITS) analysis was conducted to estimate the impact of the CEZ shortage on each antibiotic use and the cost of all parenteral antibiotics per patient day in hospitals with shortage as compared to those without shortage.

RESULTS

In the hospitals with shortage, the proportion of CEZ use to the sum of all selected antibiotics decreased (23.5-11.1%). The decrease in CEZ use was mainly offset by the use of ceftriaxone, ceftriaxone, and ampicillin/sulbactam. The CITS analysis showed a statistically significant increase in the use of broader-spectrum beta-lactams and clindamycin during the supply disruption period (flomoxef up 58.1%, cefotiam up 63.1%, cefmetazole up 14.5%, ceftriaxone up 13.9%, and clindamycin up 20.1%). The analysis showed no statistically significant change in the cost of all parenteral antibiotics per patient day.

CONCLUSIONS

During the CEZ supply disruption, there was a statistically significant increase in the use of broader-spectrum beta-lactams and clindamycin in hospitals with shortage compared with those without shortage.

Evaluating the Impact of a Pharmacist-Led Antimicrobial Stewardship Intervention at Discharge in a Community, Nonteaching Hospital

INTRODUCTION

Approximately 30% to 50% of hospital discharge antimicrobials are inappropriate. Limited data exist on approaches to improve antimicrobial prescribing practices at the time of discharge from a community hospital. Objective: To assess the impact of a comprehensive pharmacist-led antimicrobial stewardship intervention at discharge.

METHODS

We conducted a quasi-experimental, pre-post study. A biphasic intervention took place on 2 medicine units from November 2019 to May 2020 at a community hospital. Baseline data were collected, followed by prescriber education on antimicrobial stewardship to both units (education phase). Next, a pharmacist-led intervention took place on one unit (intervention phase). The primary outcome was composite appropriateness of an oral antimicrobial prescribed to an adult at the time of discharge, defined by narrow spectrum of activity, dosing, and duration of therapy. The primary outcome was assessed using Fisher exact test.

RESULTS

Baseline composite appropriateness was 30% (n = 12) on the control unit and 30.8% (n = 20) on the intervention unit. From baseline to posteducation, no significant change in composite appropriateness was found on the control (30% to 26.7%, P = 0.256) or intervention (30.8% to 19.4%, P = 0.09) unit. There was no significant difference between the education to intervention phase (26.7% vs 35%, P = 0.254) on the control unit. On the intervention unit, a significant difference in composite appropriateness was found from the education to intervention phase (19.4% vs 47.8%, P = 0.017).

CONCLUSION AND RELEVANCE

A pharmacist-led intervention improved appropriateness of oral antimicrobials prescribed at discharge. One-time education was insufficient for improving antimicrobial stewardship.

Adverse effects of antibiotics in children with cancer: are short-course antibiotics for febrile neutropenia part of the solution?

INTRODUCTION

Febrile neutropenia is a common complication experienced by children with cancer or those undergoing hematopoietic stem cell transplantation. Repeated episodes of febrile neutropenia result in cumulative exposure to broad-spectrum antibiotics with potential for a range of serious adverse effects. Short-course antibiotics, even in patients with high-risk febrile neutropenia, may offer a solution.

AREAS COVERED

This review addresses the known broad effects of antibiotics, highlights developments in understanding the relationship between cancer, antibiotics, and the gut microbiome, and discusses emerging evidence regarding long-term adverse antibiotic effects. The authors consider available evidence to guide the duration of empiric antibiotics in pediatric febrile neutropenia and directions for future research.

EXPERT OPINION

Broad-spectrum antibiotics are associated with antimicrobial resistance, Clostridioides difficile infection, invasive candidiasis, significant disturbance of the gut microbiome and may seriously impact outcomes in children with cancer or undergoing allogenic hematopoietic stem cell transplant. Short-course empiric antibiotics are likely safe in most children with febrile neutropenia and present a valuable opportunity to reduce the risks of antibiotic exposure.