Clostridium difficile infection following systemic antibiotic administration in randomised controlled trials: a systematic review and meta-analysis

Derivation of clinical predictive factors (CHIEF) for first recurrent Clostridioides difficile infection

BACKGROUND

Current models for predicting Clostridioides difficile infection (CDI) recurrence rates have a limited capacity to account for important risk factors. This study developed a clinical prediction rule for CDI recurrence.

METHODS

This retrospective cohort study evaluated 209 patients with CDI at a university hospital in Japan. Logistic regression and receiver operating characteristic curve analyses were performed to identify potential predictors (age, sex, underlying diseases, antibiotic use, acid suppressants, immunosuppressants, CDI history) of CDI recurrence.

RESULTS

Forty-five patients developed recurrent CDI. Univariate analyses identified several significant recurrence predictors (enteral feeding, inflammatory bowel diseases [IBD], community-onset CDI, severe CDI). Enteral feeding (odds ratio: 3.87, 95% confidence interval: 1.75-8.56) and IBD (odds ratio: 7.08, 95% confidence interval: 1.28-39.06) were significant factors in the multivariate analysis. The CHIEF predictive scoring system was developed using 5 relevant variables (carbapenem use, hematologic malignancy, IBD, enteral feeding, fluoroquinolone use); the area under the receiver operating characteristic curve for the CHIEF score was 0.70.

DISCUSSION

The CHIEF score incorporates useful, clinically available factors and could help identify patients at risk of recurrent CDI.

CONCLUSIONS

These findings contribute to the understanding of risk factors associated with CDI recurrence and provide support for the development of prevention strategies.

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.

Reducing antibiotic prescribing in general practice in Australia: a cluster randomised controlled trial of a multimodal intervention

BACKGROUND

The health and economic burden of antimicrobial resistance (in Australia is significant. Interventions that help guide and improve appropriate prescribing for acute respiratory tract infections in the community represent an opportunity to slow the spread of resistant bacteria. Clinicians who work in primary care are potentially the most influential health care professionals to address the problem of antimicrobial resistance, because this is where most antibiotics are prescribed.

METHODS

A cluster randomised trial was conducted comparing two parallel groups of 27 urban general practices in Queensland, Australia: 13 intervention and 14 control practices, with 56 and 54 general practitioners (GPs), respectively. This study evaluated an integrated, multifaceted evidence-based package of interventions implemented over a 6-month period. The evaluation included quantitative and qualitative components, and an economic analysis.

RESULTS

A multimodal package of interventions resulted in a reduction of 3.81 prescriptions per GP per month. This equates to 1280.16 prescriptions for the 56GPs in the intervention practices over the 6-month period. The cost per prescription avoided was A$148. The qualitative feedback showed that the interventions were well received by the GPs and did not impact on consultation time. Providing GPs with a choice of tools might enhance their uptake and support for antimicrobial stewardship in the community.

CONCLUSIONS

A multimodal package of interventions to enhance rational prescribing of antibiotics is effective, feasible and acceptable in general practice. Investment in antimicrobial stewardship strategies in primary care may ultimately provide the important returns for public health into the future.

Indications for Antibiotic Prophylaxis for Dentoalveolar Procedures

Antibiotic prophylaxis is the use of antibiotics perioperatively to prevent infections at the surgical site or distant locations. The decision to provide prophylaxis must balance risks of antibiotic resistance, adverse drug reactions, and increased health care costs with the benefit of decreasing infection. This determination has been studied extensively in patients with specific cardiac conditions and prosthetic joints. Prophylactic antibiotics in healthy patients have been shown to reduce the frequency of alveolar osteitis and decrease the failure rates of dental implants.

Fluoroquinolone-associated adverse events of interest among hospitalized veterans affairs patients with community-acquired pneumonia who were treated with a fluoroquinolone: A focus on tendonitis, Clostridioides difficile infection, and aortic aneurysm

STUDY OBJECTIVE

The objectives of this study were to (i) quantify the incidence of three concerning fluoroquinolone adverse events of interest (FQAEI, i.e., adverse tendon event (TE), clostridioides difficile infection (CDI), and aortic aneurysm/dissection (AAD)), (ii) identify the patient-level factors that predict these events, and (iii) develop clinical risk scores to estimate the predicted probabilities of each FQAEI based on patient-level covariates available on clinical presentation.

DESIGN

Retrospective cohort study.

SETTING

Upstate New York Veterans' Healthcare Administration from 2011 to 2016.

PATIENTS

Hospitalized patients with community-acquired pneumonia receiving care in the Upstate New York Veterans' Healthcare Administration from 2011 to 2016.

INTERVENTION

N/A.

MEASUREMENTS

The outcomes of interest for this study were the occurrence of TE, CDI, and AAD. We also evaluated a composite of these three outcomes, FQAEI.

MAIN RESULTS

The study population consisted of 1071 patients. The overall incidence of FQAEI, TE, AAD, and CDI was 6.5%, 1.8%, 4.5%, and 0.3%, respectively. For each outcome evaluated, the probability of the event of interest was predicted by the presence of certain comorbidities, previous healthcare exposure, choice of specific FQ antibiotic, or therapy duration. Concomitant steroids, pneumonia in preceding 180 days, and creatinine clearance <30 mL/min predicted FQAEI.

CONCLUSIONS

Individual frequencies of three important FQAEIs were quantified, and risk scores were developed to estimate the probabilities of experiencing these events to help clinicians individualize treatment decisions for patients and reduce the potential risks of select FQAEIs.

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.

A Pharmacovigilance Study Regarding the Risk of Antibiotic-Associated Clostridioides difficile Infection Based on Reports from the EudraVigilance Database: Analysis of Some of the Most Used Antibiotics in Intensive Care Units

The Gram-positive anaerobic bacterium Clostridioides difficile (CD) can produce intense exotoxins, contributing to nosocomial infections, and it is the most common cause of health-care-associated infectious diarrhea. Based on spontaneous Individual Case Safety Reports from EudraVigilance (EV), we conducted a descriptive analysis of Clostridioides difficile infection (CDI) cases that reported a spontaneous adverse reaction related to using ceftriaxone, colistimethate, ciprofloxacin, gentamicin, linezolid, meropenem, and piperacillin/tazobactam. Most ADR reports registered in EV that were related to CDI were associated with ceftriaxone (33%), ciprofloxacin (28%), and piperacillin/tazobactam (21%). Additionally, the disproportionality analysis performed showed that all studied antibiotics had a lower reporting probability when compared to clindamycin. A causal relationship between a drug and the occurrence of an adverse reaction cannot be established from EV data alone because the phenomena of underreporting, overreporting, and reporting bias may affect the results. Based on the analysis of the collected data, this study underlines the importance of surveillance and monitoring programs for the consumption of antibiotics. Furthermore, it is essential to use standardized laboratory tests to define CDI's nature accurately. To prevent this infection, specialists should collaborate and adhere strictly to antibiotic stewardship programs, hygiene practices, and isolation protocols.

Does this patient have Clostridioides difficile infection? A systematic review and meta-analysis

BACKGROUND

The clinical features and predictors of Clostridioides difficile infection overlap with many conditions.

OBJECTIVES

We performed a systematic review to evaluate the diagnostic utility of clinical features (clinical examination, risk factors, laboratory tests, and radiographic findings) associated with C. difficile.

METHODS

Systematic review and meta-analysis of diagnostic features for C. difficile.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, and Cochrane databases were searched up to September 2021.

STUDY ELIGIBILITY CRITERIA

Studies that reported clinical features of C. difficile, a valid reference standard test for confirming diagnosis of C. difficile, and a comparison among patients with a positive and negative test result.

PARTICIPANTS

Adult and paediatric patients across diverse clinical settings.

OUTCOMES

Sensitivity, specificity, likelihood ratios.

REFERENCE STANDARD

Stool nucleic acid amplification tests, enzyme immunoassays, cell cytotoxicity assay, and stool toxigenic culture.

ASSESSMENT OF RISK OF BIAS

Rational Clinical Examination Series and Quality Assessment of Diagnostic Accuracy Studies-2.

METHODS OF DATA SYNTHESIS

Univariate and bivariate analyses.

RESULTS

We screened 11 231 articles of which 40 were included, enabling the evaluation of 66 features for their diagnostic utility for C. difficile (10 clinical examination findings, 4 laboratory tests, 10 radiographic findings, prior exposure to 13 antibiotic types, and 29 clinical risk factors). Of the ten features identified on clinical examination, none were significantly clinically associated with increased likelihood of C. difficile infection. Some features that increased likelihood of C. difficile infection were stool leukocytes (LR+ 5.31, 95% CI 3.29-8.56) and hospital admission in the prior 3 months (LR+ 2.14, 95% CI 1.48-3.11). Several radiographic findings also strongly increased the likelihood of C. difficile infection like ascites (LR+ 2.91, 95% CI 1.89-4.49).

DISCUSSION

There is limited utility of bedside clinical examination alone in detecting C. difficile infection. Accurate diagnosis of C. difficile infection requires thoughtful clinical assessment for interpretation of microbiologic testing in all suspected cases.

Association of ward-level antibiotic consumption with healthcare-associated Clostridioides difficile infections: an ecological study in five German university hospitals, 2017-2019

OBJECTIVES

To analyse the influence of antibiotic consumption on healthcare-associated healthcare onset (HAHO) Clostridioides difficile infection (CDI) in a German university hospital setting.

METHODS

Monthly ward-level antibiotic consumption measured in DDD/100 patient days (pd) and CDI surveillance data from five university hospitals in the period 2017 through 2019 were analysed. Uni- and multivariable analyses were performed with generalized estimating equation models.

RESULTS

A total of 225 wards with 7347 surveillance months and 4 036 602 pd participated. With 1184 HAHO-CDI cases, there was a median incidence density of 0.17/1000 pd (IQR 0.03-0.43) across all specialties, with substantial differences among specialties. Haematology-oncology wards showed the highest median incidence density (0.67/1000 pd, IQR 0.44-1.01), followed by medical ICUs (0.45/1000 pd, IQR 0.27-0.73) and medical general wards (0.32/1000 pd, IQR 0.18-0.53). Multivariable analysis revealed carbapenem (mostly meropenem) consumption to be the only antibiotic class associated with increased HAHO-CDI incidence density. Each carbapenem DDD/100 pd administered increased the HAHO-CDI incidence density by 1.3% [incidence rate ratio (IRR) 1.013; 95% CI 1.006-1.019]. Specialty-specific analyses showed this influence only to be valid for haematological-oncological wards. Overall, factors like ward specialty (e.g. haematology-oncology ward IRR 2.961, 95% CI 2.203-3.980) or other CDI cases on ward had a stronger influence on HAHO-CDI incidence density (e.g. community-associated CDI or unknown association case in same month IRR 1.476, 95% CI 1.242-1.755) than antibiotic consumption.

CONCLUSIONS

In the German university hospital setting, monthly ward-level carbapenem consumption seems to increase the HAHO-CDI incidence density predominantly on haematological-oncological wards. Furthermore, other patient-specific factors seem to be equally important to control HAHO-CDI.

Comparative effectiveness and safety of antibiotic prophylaxis during induction chemotherapy in children with acute leukaemia: a systematic review and meta-analysis

BACKGROUND

Bacterial infections are common during induction therapy in children and adolescents with acute leukaemia and may cause infection-related mortality.

AIM

To determine the efficacy and safety of prophylactic antibiotics in paediatric patients with acute leukaemia receiving induction chemotherapy.

METHODS

From three English databases and four Chinese databases, we searched for randomized controlled trials (RCTs) and cohort studies that compared prophylactic antibiotics to placebo, no prophylaxis, or that compared one antibiotic versus another in paediatric patients with acute leukaemia undergoing induction chemotherapy. Two reviewers independently screened the studies, extracted data, and assessed the risk of bias using Cochrane Risk of Bias 2 tool and Newcastle-Ottawa Scale, and the certainty of evidence using Grading of Recommendations Assessment, Development, and Evaluation (GRADE).

FINDINGS

Two RCTs and ten cohort studies were finally included. For children with acute lymphoblastic leukaemia, antibiotic prophylaxis, including levofloxacin, sulfamethoxazole-trimethoprim, or other antibiotics, probably reduced bacteraemia (risk ratio (RR): 0.44; 95% confidence interval (CI): 0.33-0.60; moderate certainty) without significantly increasing Clostridioides difficile infection (CDI) or invasive fungal infection. Levofloxacin reduced the CDI rate (RR: 0.08; 95% CI: 0.01-0.62; high certainty). Ciprofloxacin prophylaxis probably reduced infection-related mortality (RR: 0.12; 95% CI: 0.01-0.97; moderate certainty). In children with acute myeloid leukaemia, ciprofloxacin plus vancomycin may reduce febrile neutropenia (RR: 0.79; 95% CI: 0.66-0.94; low certainty). Individual studies indicated that prophylaxis increased antibiotic exposure but reduced non-preventive antibiotic exposure.

CONCLUSION

In children with acute leukaemia undergoing induction therapy, antibiotic prophylaxis may improve the bacterial infection and mortality.

Faecal Microbiota Transplantation is a simple, effective and safe treatment in the management of C. difficile infection in daily clinical practice

INTRODUCTION

Faecal microbiota transplantation (FMT) is a treatment supported by wide scientific evidence and proved to be very effective in the management of Clostridioides difficile infection (CDI). The objective of this study is to analyze its effectiveness and safety in a real clinical practice setting.

METHODS

Retrospective, single-center and descriptive observational study in which all FMT performed between May 2016 and December 2020 were included. Technical success was defined as the successful administration of the faecal preparation in the patient's gastrointestinal tract and clinical success the disappearance of diarrhoea in the first 72 h after the procedure with no relapse within the following 8 weeks after the therapy was started.

RESULTS

15 FMT were performed in 13 patients. Median age was 79 years (range: 40-98 years); being 60% women and 33.3% depedent persons. The indication for FMT was recurrent CDI in 84.6%. All FMTs were performed by colonoscopy and from related donors. With a first procedure, the FMT was effective in 11 of 13 patients (84.61%; 95% CI; 54.55-98.07). Time until resolution of symptoms was less than 48 h in all cases. Post-transplant follow-up was 25.66 ± 17.5 months. No significant short or long-term complications were recorded at follow-up.

CONCLUSION

TMF is a simple, effective and safe procedure in CD infection, even in elderly patients or those with great comorbidities.

Highly versus less bioavailable oral antibiotics in the treatment of gram-negative bloodstream infections: a propensity-matched cohort analysis

OBJECTIVES

In this study, we evaluated the clinical outcomes associated with the use of highly bioavailable oral antibiotics (fluoroquinolones and trimethoprim-sulfamethoxazole) compared with the less-bioavailable oral antibiotics (β-lactams) in gram-negative bloodstream infections (BSIs).

METHODS

Among hospitalized older adult patients in Ontario, Canada, discharged home on oral treatment for gram-negative BSI between 1 January 2017 and 31 December 2019, we used a matched cohort design to compare outcomes among those receiving highly versus less-bioavailable agents; hard-matching 1:1 on sex, BSI pathogen (Escherichia coli vs. non-E. coli), and infection source (urinary vs. non-urinary/unknown source) along with a propensity score, incorporating specific pathogen, patient, and infection characteristics. The primary outcome was the composite of 90-day all-cause mortality, recurrent BSI with the same pathogen (genus and species), and re-admission to any Ontario hospital.

RESULTS

A total of 2012 patients were included in the study (1006 in each bioavailability category). Those who received highly (compared with less) bioavailable antibiotics at discharge had lower rates of the composite outcome (171/1006 [17.0%] vs. 216/1006 [21.5%]), adjusted odds ratio being 0.74 (95% CI, 0.60-0.92). Recurrent BSI at 90 days was the main driver for the composite outcome occurring in 64 (5.4%) and 107 (9.4%) patients of the highly and less-bioavailable groups, respectively (p < 0.001) (adjusted odds ratio, 0.56; 95% CI, 0.40-0.78).

DISCUSSION

Use of highly (compared with less) bioavailable antibiotics at discharge was associated with significantly better clinical outcomes among patients with gram-negative BSIs.

Daptomycin for the treatment of acute bacterial meningitis: a narrative review

BACKGROUND

There is a growing interest in the utilization of daptomycin for the treatment of multi-drug resistant, Gram-positive infections. Pharmacokinetic studies suggest that daptomycin could penetrate into the cerebrospinal fluid, albeit to a small extent. The objective of this review was to evaluate the available clinical evidence for daptomycin use in acute bacterial meningitis of both pediatric and adult patients.

METHODS

Electronic databases were searched up to June 2022 for studies published on the topic. The inclusion criteria were met if the study reported the use of intravenous daptomycin (more than a single dose) for the treatment of diagnosed acute bacterial meningitis.

RESULTS

A total of 21 case reports were identified that met the inclusion criteria. These suggest that daptomycin could be safe and effective alternative in achieving clinical cure of meningitis. In these studies, daptomycin was used in the event of treatment failure, patient intolerance, or bacterial resistance to first-line agents.

CONCLUSIONS

Daptomycin has potential to be an alternative to standard care for meningitis caused by Gram-positive bacteria in the future; however, more robust research is required to establish an optimal dosing regimen, duration of therapy, and place in therapy for the management of meningitis.

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.

A novel approach for combining the metagenome, metaresistome, metareplicome and causal inference to determine the microbes and their antibiotic resistance gene repertoire that contribute to dysbiosis

The use of whole metagenomic data to infer the relative abundance of all its microbes is well established. The same data can be used to determine the replication rate of all eubacterial taxa with circular chromosomes. Despite their availability, the replication rate profiles (metareplicome) have not been fully exploited in microbiome analyses. Another relatively new approach is the application of causal inferencing to analyse microbiome data that goes beyond correlational studies. A novel scalable pipeline called MeRRCI (Metagenome, metaResistome, and metaReplicome for Causal Inferencing) was developed. MeRRCI combines efficient computation of the metagenome (bacterial relative abundance), metaresistome (antimicrobial gene abundance) and metareplicome (replication rates), and integrates environmental variables (metadata) for causality analysis using Bayesian networks. MeRRCI was applied to an infant gut microbiome data set to investigate the microbial community's response to antibiotics. Our analysis suggests that the current treatment stratagem contributes to preterm infant gut dysbiosis, allowing a proliferation of pathobionts. The study highlights the specific antibacterial resistance genes that may contribute to exponential cell division in the presence of antibiotics for various pathogens, namely Klebsiella pneumoniae, Citrobacter freundii, Staphylococcus epidermidis, Veilonella parvula and Clostridium perfringens. These organisms often contribute to the harmful long-term sequelae seen in these young infants.

Fluoroquinolone stewardship at a community health system: A decade in review

OBJECTIVE

To describe inpatient fluoroquinolone use and susceptibility data over a 10-year period after the implementation of an antimicrobial stewardship program (ASP) led by an infectious diseases pharmacist starting in 2011.

DESIGN

Retrospective surveillance study.

SETTING

Large community health system.

METHODS

Fluoroquinolone use was quantified by days of therapy (DOT) per 1,000 patient days (PD) and reported quarterly. Use data are reported for inpatients from 2016 to 2020. Levofloxacin susceptibility is reported for Pseudomonas aeruginosa and Escherichia coli for inpatients from 2011 to 2020 at a 4 adult-hospital health system.

RESULTS

Inpatient fluoroquinolone use decreased by 74% over a 5-year period, with an average decrease of 3.45 DOT per 1,000 PD per quarter (P < .001). Over a 10-year period, inpatient levofloxacin susceptibility increased by 57% for P. aeruginosa and by 15% for E. coli. P. aeruginosa susceptibility to levofloxacin increased by an average of 2.73% per year (P < .001) and had a strong negative correlation with fluoroquinolone use, r = -0.99 (P = .002). E. coli susceptibility to levofloxacin increased by an average of 1.33% per year (P < .001) and had a strong negative correlation with fluoroquinolone use, r = -0.95 (P = .015).

CONCLUSIONS

A substantial decrease in fluoroquinolone use and increase in P. aeruginosa and E. coli levofloxacin susceptibility was observed after implementation of an antimicrobial stewardship program. These results demonstrate the value of stewardship services and highlight the effectiveness of an infectious diseases pharmacist led antimicrobial stewardship program.

Extended-Spectrum Antibiotics for Community-Acquired Pneumonia with a Low Risk of Drug-Resistant Pathogens

OBJECTIVES

The potential hazards of extended-spectrum antibiotic therapy for patients with community-acquired pneumonia (CAP) with low risk of drug-resistant pathogens (DRPs) remains unclear, although risk assessment for DRPs is essential to determine the initial antibiotics to be administered. The study objective is to assess the effect of unnecessary extended-spectrum therapy on mortality of such patients.

METHODS

A post-hoc analysis was conducted after a prospective multicenter observational study for CAP. Multivariable logistic regression analysis was performed to assess the effect of extended-spectrum therapy on 30-day mortality. Three sensitivity analyses, including propensity score analysis to confirm the robustness of findings, were also performed.

RESULTS

Among 750 patients with CAP, 416 with CAP with a low risk of DRPs were analyzed; of these, 257 underwent standard therapy and 159 underwent extended-spectrum therapy. The 30-day mortality was 3.9% and 13.8% in the standard and extended-spectrum therapy groups, respectively. Primary analysis revealed that extended-spectrum therapy was associated with increased 30-day mortality compared with standard therapy (adjusted odds ratio, 2.82; 95% confidence interval, 1.20-6.66). The results of the sensitivity analyses were consistent with those of the primary analysis.

CONCLUSIONS

Physicians should assess the risk of DRPs when determining the empirical antibiotic therapy and should refrain from administering unnecessary extended-spectrum antibiotics for patients with CAP with a low risk of DRPs.

Criteria Restricting Inappropriate Meropenem Empiricism (CRIME): a quasi-experimental carbapenem restriction pilot at a large academic medical centre

The broad-spectrum activity of carbapenems makes them appealing for empirical use; however, they are associated with development of Clostridioides difficile infection (CDI) and multidrug resistance. Selective carbapenem use is vital in maintaining their effectiveness. We examined the impact of meropenem restriction criteria on utilisation and patient outcomes. This quasi-experimental study was conducted at a single academic medical centre after medication use evaluation found frequent inappropriate meropenem utilisation. Antimicrobial stewardship-led restriction criteria were developed and implemented in February 2022. Investigators aimed to determine how restriction criteria affected meropenem utilisation across 8 weeks in the pre- (February-April 2020) versus post-implementation period (February-April 2022). The primary outcome was inappropriateness of meropenem utilisation. Secondary outcomes included days of therapy per 1000 patient-days (DOT/1000 PD), hospital length of stay (LOS), CDI Standardized Infection Ratio (SIR), and acquisition cost. Across the 8-week timeframes, reductions in inappropriate meropenem use (64.5% vs. 12.8%; P < 0.001), duration of therapy [5.8 (3.2-7.3) vs. 2.4 (1.0-5.5) days; P < 0.001] and utilisation (30.5 vs. 8.3 DOT/1000 PD; P < 0.001) pre- versus post-implementation were observed. Total meropenem orders decreased by 65% (P < 0.001). Median hospital LOS also decreased between periods [11.9 (7.8-20.4) vs. 9.2 (5.4-15.2) days], although not statistically significant (P = 0.051). There was no difference in CDI SIR (0.1 vs. 0.1; P = 0.99). Projected annual cost savings were ∼US$57 300. Implementation of antimicrobial stewardship-initiated restriction criteria can reduce inappropriate meropenem utilisation, overall number of orders, and total duration of therapy.

Oral fidaxomicin versus vancomycin for the treatment of Clostridioides difficile infection: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Fidaxomicin (FDX) has received considerable attention as a novel therapeutic alternative agent to vancomycin (VCM) for Clostridioides difficile infection (CDI). However, the superiority and efficacy profile of FDX are not sufficiently determined by high-quality evidence. This study aimed to clarify the superiority of FDX for CDI treatment through a systematic review and meta-analysis.

METHODS

We conducted a meta-analysis of randomized controlled trials (RCTs) which evaluated the efficacy and safety of FDX and VCM in patients with CDI. Electronic databases (PubMed, Cochrane Library, Web of Science, and Clinicaltrials.gov) were searched for studies published until October 15, 2021. The primary endpoint was global cure. The secondary endpoints were clinical cure, recurrence, and adverse event. Risk ratios (RRs), risk differences (RDs), and 95% confidence intervals were calculated using Mantel-Haenszel random-effects model. The risk of bias was assessed using Cochrane Handbook for Systematic Reviews of Interventions and Assessment Criteria.

RESULTS

Six RCTs were included in this meta-analysis. Compared to VCM, FDX was associated with significantly higher global cure rates (RR = 1.18, P < 0.00001; RD = 0.11, 95% CI = 0.07-0.16). In addition, clinical cure rates were comparable between FDX and VCM (P = 0.31). FDX was associated with significantly lower recurrence rates compared to VCM (RR = 0.59, P < 0.0001). In addition, adverse event rates were not significantly different between the drugs (P = 0.41).

CONCLUSION

FDX achieves significantly higher global cure rates and lower recurrence rates and is comparable to VCM in clinical cure rates and adverse event rates in patients with CDI. Collectively, FDX is superior to VCM as a therapeutic agent for CDI.

Diluted Fecal Community Transplant Restores Clostridioides difficile Colonization Resistance to Antibiotic-Perturbed Murine Communities

Fecal communities transplanted into individuals can eliminate recurrent Clostridioides difficile infection (CDI) with high efficacy. However, this treatment is only used once CDI becomes resistant to antibiotics or has recurred multiple times. We sought to investigate whether a fecal community transplant (FCT) pretreatment could be used to prevent CDI altogether. We treated male C57BL/6 mice with either clindamycin, cefoperazone, or streptomycin and then inoculated them with the microbial community from untreated mice before challenge with C. difficile. We measured colonization and sequenced the V4 region of the 16S rRNA gene to understand the dynamics of the murine fecal community in response to the FCT and C. difficile challenge. Clindamycin-treated mice became colonized with C. difficile but cleared it naturally and did not benefit from the FCT. Cefoperazone-treated mice became colonized by C. difficile, but the FCT enabled clearance of C. difficile. In streptomycin-treated mice, the FCT was able to prevent C. difficile from colonizing. We then diluted the FCT and repeated the experiments. Cefoperazone-treated mice no longer cleared C. difficile. However, streptomycin-treated mice colonized with 1:10² dilutions resisted C. difficile colonization. Streptomycin-treated mice that received an FCT diluted 1:10³ became colonized with C. difficile but later cleared the infection. In streptomycin-treated mice, inhibition of C. difficile was associated with increased relative abundance of a group of bacteria related to Porphyromonadaceae and Lachnospiraceae. These data demonstrate that C. difficile colonization resistance can be restored to a susceptible community with an FCT as long as it complements the missing populations.

Impact of Hospital Environmental Cleaning with a Potassium Peroxymonosulphate-Based Environmental Disinfectant and Antimicrobial Stewardship on the Reduction of Hospital-Onset Clostridioides difficile Infections

BACKGROUND

A 1% potassium peroxymonosulphate-based environmental disinfectant (PPED) produces sodium hypochlorite when combined with sodium chloride, which functions as a disinfectant. However, little is known about the impact of hospital cleaning with PPED on hospital-onset Clostridioides difficile infection (HO-CDI).

AIM

To reduce HO-CDI, we promote antimicrobial stewardship and hospital ward cleaning with PPED. This study was conducted to evaluate their impact.

METHODS

We began a promotion of post-prescription review with feedback for broad-spectrum antimicrobials and hospital ward cleaning with PPED. We reviewed the ratio of HO-CDI, PPED consumption, and days of therapy (DOT) of broad-spectrum antimicrobials between July 2014 and March 2018, dividing this time into the pre-promotion (July 2014 to June 2015) and post-promotion periods (July 2015 to March 2018).

FINDINGS

Using interrupted time series analysis, an immediate significant change in HO-CDI was observed after intervention (P = 0.03), although a downward trend was not observed over this period (P = 0.19). Trends in PPED consumption significantly changed over this period (P = 0.02). DOT of carbapenems decreased immediately after the intervention began (P < 0.01). A Poisson regression analysis showed that PPED consumption and DOT of carbapenems were independent factors affecting HO-CDI (P = 0.039 and 0.016, respectively).

CONCLUSION

We revealed that DOT of carbapenems and use of PPED were associated with the HO-CDI ratio and that both interventions reduced the rate of HO-CDI. This is the first report on the impact of hospital ward cleaning with PPED on the reduction of HO-CDI.

Antimicrobial safety considerations in critically ill patients: part II: focused on anti-microbial toxicities

INTRODUCTION

Antibiotic prescription is a challenging issue in critical care settings. Different pharmacokinetic and pharmacodynamic properties, polypharmacy, drug interactions, and high incidence of multidrug-resistant microorganisms in this population can influence the selection, safety, and efficacy of prescribed antibiotics.

AREAS COVERED

In the current article we searched PubMed, Scopus and Google Scholar for neurotoxicities, hematologic toxicity and fluid stewardship in intensive care units.

EXPERT OPINION

Critically ill patients who receive antimicrobial agents should be monitored for neurological, hematologic toxicities especially seizure, thrombocytopenia, and clostridioides infections. Other toxicities including QTc prolongation, electrolyte disturbances, liver enzyme elevation, and infusion-related reactions were being considered. Other changes, including fluid overload, hypoalbuminemia, augmented renal clearance, increased cardiac outputs in septic shock, and acute kidney injury, may influence treatment efficiency and patient outcome.

Bioengineered Probiotics: Synthetic Biology Can Provide Live Cell Therapeutics for the Treatment of Foodborne Diseases

The rising prevalence of antibiotic resistant microbial pathogens presents an ominous health and economic challenge to modern society. The discovery and large-scale development of antibiotic drugs in previous decades was transformational, providing cheap, effective treatment for what would previously have been a lethal infection. As microbial strains resistant to many or even all antibiotic drug treatments have evolved, there is an urgent need for new drugs or antimicrobial treatments to control these pathogens. The ability to sequence and mine the genomes of an increasing number of microbial strains from previously unexplored environments has the potential to identify new natural product antibiotic biosynthesis pathways. This coupled with the power of synthetic biology to generate new production chassis, biosensors and “weaponized” live cell therapeutics may provide new means to combat the rapidly evolving threat of drug resistant microbial pathogens. This review focuses on the application of synthetic biology to construct probiotic strains that have been endowed with functionalities allowing them to identify, compete with and in some cases kill microbial pathogens as well as stimulate host immunity. Weaponized probiotics may have the greatest potential for use against pathogens that infect the gastrointestinal tract: Vibrio cholerae, Staphylococcus aureus, Clostridium perfringens and Clostridioides difficile. The potential benefits of engineered probiotics are highlighted along with the challenges that must still be met before these intriguing and exciting new therapeutic tools can be widely deployed.

Decalogue for the selection of oral antibiotics for lower respiratory tract infections

Lower respiratory tract infections, including chronic obstructive pulmonary disease exacerbations (COPD-E) and community acquired pneumonia (CAP), are one of the most frequent reasons for consultation in primary care and hospital emergency departments, and are the cause of a high prescription of antimicrobial agents. The selection of the most appropriate oral antibiotic treatment is based on different aspects and includes to first consider a bacterial aetiology and not a viral infection, to know the bacterial pathogen that most frequently cause these infections and the frequency of their local antimicrobial resistance. Treatment should also be prescribed quickly and antibiotics should be selected among those with a quicker mode of action, achieving the greatest effect in the shortest time and with the fewest adverse effects (toxicity, interactions, resistance and/or ecological impact). Whenever possible, antimicrobials should be rotated and diversified and switched to the oral route as soon as possible. With these premises, the oral treatment guidelines for mild or moderate COPD-E and CAP in Spain include as first options beta-lactam antibiotics (amoxicillin and amoxicillin-clavulanate and cefditoren), in certain situations associated with a macrolide, and relegating fluoroquinolones as an alternative, except in cases where the presence of Pseudomonas aeruginosa is suspected.

Frontiers in antibiotic alternatives for Clostridioides difficile infection

Clostridioides difficile (C. difficile) is a gram-positive, anaerobic spore-forming bacterium and a major cause of antibiotic-associated diarrhea. Humans are naturally resistant to C. difficile infection (CDI) owing to the protection provided by healthy gut microbiota. When the gut microbiota is disturbed, C. difficile can colonize, produce toxins, and manifest clinical symptoms, ranging from asymptomatic diarrhea and colitis to death. Despite the steady-if not rising-prevalence of CDI, it will certainly become more problematic in a world of antibiotic overuse and the post-antibiotic era. C. difficile is naturally resistant to most of the currently used antibiotics as it uses multiple resistance mechanisms. Therefore, current CDI treatment regimens are extremely limited to only a few antibiotics, which include vancomycin, fidaxomicin, and metronidazole. Therefore, one of the main challenges experienced by the scientific community is the development of alternative approaches to control and treat CDI. In this Frontier article, we collectively summarize recent advances in alternative treatment approaches for CDI. Over the past few years, several studies have reported on natural product-derived compounds, drug repurposing, high-throughput library screening, phage therapy, and fecal microbiota transplantation. We also include an update on vaccine development, pre- and pro-biotics for CDI, and toxin antidote approaches. These measures tackle CDI at every stage of disease pathology via multiple mechanisms. We also discuss the gaps and concerns in these developments. The next epidemic of CDI is not a matter of if but a matter of when. Therefore, being well-equipped with a collection of alternative therapeutics is necessary and should be prioritized.

Fluoroquinolone antibiotics and adverse events

Fluoroquinolones are broad-spectrum antibiotics with good oral bioavailability. They are used for the treatment of a wide variety of infections, but there are restrictions on prescribing these drugs.

Epidemiological studies have reported an increased risk of rare adverse effects. These include tendinopathy and tendon rupture, peripheral neuropathy and aortic aneurysm.

Safe prescribing of fluroquinolones requires recognition of patients with risk factors for toxicity. Prompt drug discontinuation is recommended in the event of an adverse reaction.

Practising antimicrobial stewardship by prescribing fluoroquinolones only when alternative drugs are unavailable is also key to limiting adverse events and antibiotic resistance.

Acceptability and effectiveness of antimicrobial stewardship implementation strategies on fluoroquinolone prescribing

OBJECTIVE

To assess the effectiveness and acceptability of antimicrobial stewardship-focused implementation strategies on inpatient fluoroquinolones.

METHODS

Stewardship champions at 15 hospitals were surveyed regarding the use and acceptability of strategies to improve fluoroquinolone prescribing. Antibiotic days of therapy (DOT) per 1,000 days present (DP) for sites with and without prospective audit and feedback (PAF) and/or prior approval were compared.

RESULTS

Among all of the sites, 60% had PAF or prior approval implemented for fluoroquinolones. Compared to sites using neither strategy (64.2 ± 34.4 DOT/DP), fluoroquinolone prescribing rates were lower for sites that employed PAF and/or prior approval (35.5 ± 9.8; P = .03) and decreased from 2017 to 2018 (P < .001). This decrease occurred without an increase in advanced-generation cephalosporins. Total antibiotic rates were 13% lower for sites with PAF and/or prior approval, but this difference did not reach statistical significance (P = .20). Sites reporting that PAF and/or prior approval were "completely" accepted had lower fluoroquinolone rates than sites where it was "moderately" accepted (34.2 ± 5.7 vs 48.7 ± 4.5; P < .01). Sites reported that clinical pathways and/or local guidelines (93%), prior approval (93%), and order forms (80%) "would" or "may" be effective in improving fluoroquinolone use. Although most sites (73%) indicated that requiring infectious disease consults would or may be effective in improving fluoroquinolones, 87% perceived implementation to be difficult.

CONCLUSIONS

PAF and prior approval implementation strategies focused on fluoroquinolones were associated with significantly lower fluoroquinolone prescribing rates and nonsignificant decreases in total antibiotic use, suggesting limited evidence for class substitution. The association of acceptability of strategies with lower rates highlights the importance of culture. These results may indicate increased acceptability of implementation strategies and/or sensitivity to FDA warnings.

Impact of Cefazolin Shortage on Clinical Outcomes of Adult Patients with Bacteremia Caused by Methicillin-Susceptible Staphylococcus aureus in a Tertiary Care University Hospital

Cefazolin is an essential antibiotic used for treating bacteremia; in particular, it is recommended as a first-line agent for infections caused by methicillin-susceptible Staphylococcusaureus (MSSA). In March 2019, problems with a major antibiotic supplier caused a critical shortage of cefazolin in Japan; however, the impact of the cefazolin shortage on clinical outcomes remains unknown. This study aimed to evaluate the effect of the cefazolin shortage in patients with MSSA bacteremia. Data from 75 patients were compared between the pre-shortage (March 2018–January 2019, n = 39) and post-shortage (March 2019–January 2020, n = 36) periods. There were no significant differences in the demographic characteristics between the two groups, and the cefazolin shortage did not worsen clinical outcomes such as adverse drug reactions, treatment failure, and 30-day mortality. In the post-shortage group, ampicillin/sulbactam and benzylpenicillin were more frequently administered as alternative antibiotics for empirical and definitive therapy (10% vs. 31%, p = 0.042; 0% vs. 19%, p = 0.004, respectively). Multivariate analysis revealed that the broad-spectrum antibiotics for definitive therapy, such as antipseudomonal penicillin, were associated with treatment failure in patients with MSSA bacteremia (OR = 17, p = 0.003). Hence, narrow-spectrum antibiotics should be prescribed for MSSA bacteremia as alternatives during a cefazolin shortage.

Potential Cost Savings Associated with Targeted Substitution of Current Guideline-Concordant Inpatient Agents with Omadacycline for the Treatment of Adult Hospitalized Patients with Community-Acquired Bacterial Pneumonia at High Risk for Clostridioides difficile Infections: Results of Healthcare-Decision Analytic Model from the United States Hospital Perspective

Introduction: Approximately 3% of hospitalized patients with community-acquired bacterial pneumonia (CABP) develop healthcare-associated Clostridioides difficile infection (HCA-CDI). The validated Davis risk score (DRS) indicates that patients with a DRS ≥ 6 are at an increased risk of 30-day HCA-CDI. In the phase 3 OPTIC CABP study, 14% of CABP patients with DRS ≥ 6 who received moxifloxacin developed CDI vs. 0% for omadacycline. This study assessed the potential economic impact of substituting current guideline-concordant CABP inpatient treatments with omadacycline in hospitalized CABP patients with a DRS ≥ 6 across US hospitals. Methods: A deterministic healthcare-decision analytic model was developed. The model population was hospitalized adult CABP patients with a DRS ≥ 6 across US hospitals (100,000 patients). In the guideline-concordant arm, 14% of CABP patients with DRS ≥ 6 were assumed to develop an HCA-CDI, each costing USD 20,100. In the omadacycline arm, 5 days of therapy was calculated for the entire model population. Results: The use of omadacycline in place of guideline-concordant CABP inpatient treatments for CABP patients with DRS ≥ 6 was estimated to result in cost savings of USD 55.4 million annually across US hospitals. Conclusion: The findings of this simulated model suggest that prioritizing the use of omadacycline over current CABP treatments in hospitalized CABP with a DRS ≥ 6 may potentially reduce attributable HCA-CDI costs. The findings are not unique to omadacycline and could be applied to any antibiotic that confers a lower risk of HCA-CDI relative to current CABP inpatient treatments.

Incongruence between dominant commensal donor microbes in recipient feces post fecal transplant and response to anti-PD-1 immunotherapy

Background

To understand inter-individual variability of fecal microbe transplantation (FMT) to enhance anti-PD-1 immunotherapy (IT) for melanoma, we analyzed the data sets from two recent publications with a microbial strain-tracking tool to determine if donor strains were dominant in the recipient feces following FMT.

Results

Analysis of the Baruch et al. data set found that the presence of commensal donor microbes in recipient feces post-FMT did not correlate with the patient response to IT. From the Davar et al., data set, we found 4 patients that responded to IT had donor’s related strain post-FMT, while 2 patients that did not respond to the IT also had donor’s strain post-FMT. Importantly, we identified no donor microbes in the feces in one recipient post-FMT that responded to IT. Furthermore, in depth analysis from two patients who responded to IT revealed both donor and recipient strains at different times post-FMT. Colonization of the gastrointestinal tract niches is important for the interaction with the host immune system. Using a separate data set, we show that mucosa from the cecum, transverse colon, and sigmoid colon share strains, providing a large reservoir of niches containing recipient microbes.

Conclusions

We demonstrated using strain-tracking analysis individual variation with the respect to the presence of fecal dominant donor microbes in the recipient following FMT that did not correlate with the response to anti-PD-1 immunotherapy. The inter-individual differences of FMT to enhance IT might be explained by the variability of the donor microbes to occupy and outcompete recipient microbes for the gastrointestinal niches. The result from our study supports the use of new approaches to clear the niches in the gastrointestinal tract to promote donor colonization to reduce inter-individual variability of IT for melanoma and potentially other cancers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-021-02312-0.

Antibiotic exposure and the risk of hospital-acquired diarrhoea and Clostridioides difficile infection: a cohort study

BACKGROUND

Hospital-acquired diarrhoea (HAD) and Clostridioides difficile infection (CDI) may be triggered by antibiotic use.

OBJECTIVES

To determine the effect of specific antibiotic agents and duration of therapy on the risk of HAD and CDI.

PATIENTS AND METHODS

A single-centre retrospective cohort study was conducted between May 2012 and December 2014 in the internal medicine division. HAD was defined based on documentation of diarrhoea in the medical record or an uncancelled C. difficile test in the laboratory database. CDI was diagnosed using a two-step test (initial glutamate dehydrogenase and toxin A/B EIA, with PCR for discrepant results). Outcomes first occurred on hospital Day 4 or later. Treatment with antibiotics and days of therapy were modelled.

RESULTS

In 29 063 hospitalizations there were 970 HAD events [incidence rate per 10 000 patient days (IR) = 38.5] and 105 CDI events (IR = 3.9). Any antibiotic treatment increased the risk of HAD [adjusted relative risk (aRR) 2.79; 95% CI 2.27-3.43] and CDI (aRR 5.31; 95% CI 2.23-12.69). Each day of β-lactam/β-lactamase inhibitors (βL/βLIs), carbapenems, IV glycopeptides and metronidazole increased the risk of HAD. Each day of βL/βLIs, third- and fourth-generation cephalosporins and carbapenems increased the risk of CDI by over 2%.

CONCLUSIONS

Preventing HAD and CDI should focus on reducing the overall use of antibiotics and shortening antibiotic exposure, rather than focusing on specific agents.

Why Was There Ever a Warning Not to Use Cephalosporins in the Setting of a Penicillin "Allergy"?

It is now well-established that avoiding β-lactam antibiotics, when they are the drugs of choice, results in significantly worse long-term global outcomes for patients. Much of this avoidable morbidity has been caused by widespread warnings in electronic health care record systems not to use cephalosporins in the setting of penicillin allergy. High rates, up to 1000-fold higher than now seen, of immunologically mediated reactions were associated with early impure penicillin preparations. This instilled a rational fear of β-lactam-associated anaphylaxis in generations of physicians. In the late 1970s, several editorial comments regarding a potential increased risk to patients given cephalosporins who had a history of a penicillin allergy resulted in the warning that became imbedded in the culture of medicine. Over the past 40 years, compelling data have been developed that refute this warning and showed that the risks of avoiding cephalosporins outweighed the benefits. In late 2017, Kaiser Permanente Southern California completely removed all warnings not to use cephalosporins in the setting of a penicillin allergy. The results have recently been published in JAMA Network Open. This Rostrum article provides some of the backstory on the establishment and removal of this warning for physicians who trained over the past 30 years.

Practical Gram-Scale Synthesis of Iboxamycin, a Potent Antibiotic Candidate

A gram-scale synthesis of iboxamycin, an antibiotic candidate bearing a fused bicyclic amino acid residue, is presented. A pivotal transformation in the route involves an intramolecular hydrosilylation-oxidation sequence to set the ring-fusion stereocenters of the bicyclic scaffold. Other notable features of the synthesis include a high-yielding, highly diastereoselective alkylation of a pseudoephenamine amide, a convergent sp³-sp² Negishi coupling, and a one-pot transacetalization-reduction reaction to form the target compound's oxepane ring. Implementation of this synthetic strategy has provided ample quantities of iboxamycin to allow for its in vivo profiling in murine models of infection.

Safety of administering cefazolin versus other antibiotics in penicillin-allergic patients for surgical prophylaxis at a major Canadian teaching hospital

BACKGROUND

Cefazolin surgical prophylaxis is associated with better patient outcomes; however, its use in penicillin-allergic patients is controversial. We evaluated the safety of cefazolin as surgical prophylaxis in penicillin-allergic patients, including those with anaphylaxis histories.

METHODS

We conducted a pre and postintervention quality improvement evaluation of an institution-wide policy change at a tertiary-care hospital, before (October 2017-January 2018), during (February 2018-September 2018), and after (October 2018-October 2019) transition to routine cefazolin prophylaxis for penicillin-allergic patients, including those with anaphylaxis histories but excluding severe delayed reactions (eg, Stevens-Johnson syndrome). Retrospective data was collected on all surgical prophylaxis patients with penicillin-anaphylactic histories between October 2017 and September 2018. From October 2018, we prospectively reviewed adverse events with cefazolin. Primary outcome was adverse events in penicillin-allergic patients receiving cefazolin perioperatively.

RESULTS

From October 2017 to October 2019, 27,467 operations were performed. Of 220 patients with penicillin-anaphylactic histories reviewed prior to the full policy change, no statistically significant differences were reported in allergic reactions (P = .70), surgical site infections (P = 1.00), or adverse events (P = .32) with cefazolin compared to other antibiotics. Postpolicy implementation, cefazolin usage increased 18.2%, while vancomycin and clindamycin decreased by 11.4% and 62.0%, respectively. No anaphylaxis was documented in penicillin-allergic patients receiving cefazolin in either the review or quality assurance follow-up after the change. Of 3 patients developing reactions to cefazolin, none had histories of penicillin allergy. Surgical site infection rates were similar between pre and postpolicy time periods (P = .842).

CONCLUSION

Administration of cefazolin in penicillin-anaphylactic patients for surgical prophylaxis appears to be safe.

Microbiota-based markers predictive of development of Clostridioides difficile infection

Antibiotic-induced modulation of the intestinal microbiota can lead to Clostridioides difficile infection (CDI), which is associated with considerable morbidity, mortality, and healthcare-costs globally. Therefore, identification of markers predictive of CDI could substantially contribute to guiding therapy and decreasing the infection burden. Here, we analyze the intestinal microbiota of hospitalized patients at increased CDI risk in a prospective, 90-day cohort-study before and after antibiotic treatment and at diarrhea onset. We show that patients developing CDI already exhibit significantly lower diversity before antibiotic treatment and a distinct microbiota enriched in Enterococcus and depleted of Ruminococcus, Blautia, Prevotella and Bifidobacterium compared to non-CDI patients. We find that antibiotic treatment-induced dysbiosis is class-specific with beta-lactams further increasing enterococcal abundance. Our findings, validated in an independent prospective patient cohort developing CDI, can be exploited to enrich for high-risk patients in prospective clinical trials, and to develop predictive microbiota-based diagnostics for management of patients at risk for CDI.

Advances and required improvements in methods to diagnosing Clostridioides difficile infections in the healthcare setting

INTRODUCTION

Clostrididioides difficile is associated with adverse clinical outcomes and increased morbidity, mortality, length of hospital stay, and health-care costs.Areas Covered: We searched relevant papers in PubMed for the last 10 years. In major papers, we scanned the bibliographies to ensure that important articles were included. This review addresses the evolving epidemiology of Clostridioides difficile infection (CDI) and discusses novel methods/approaches for improving the diagnosis of this important disease.

EXPERT OPINION

No single diagnostic test to date has demonstrated optimum sensitivity and specificity for detection of CDI. Many institutions have developed multi-step algorithms consistent with guidelines established by various professional societies. Some institutions have successfully tried to improve the pretest probability of molecular assays by implementing appropriate sample rejection criteria and establishing best practice alerts at the time of electronic order entry. Others have established PCR cycle threshold cutoffs to attempt to differentiate symptomatic patients from asymptomatic carriers or to make predictions about severity of disease with variable success. As research advances our understanding of C. difficile pathogenesis and pathophysiology, more information on CDI specific biomarkers is emerging. Finally, assessments of the microbiome and metabolome may expand the diagnostic armamentarium with advances in mass spectrometry and sequencing technologies.

Review of Guidelines for Dental Antibiotic Prophylaxis for Prevention of Endocarditis and Prosthetic Joint Infections and Need for Dental Stewardship

Dentists prescribe 10% of all outpatient antibiotic prescriptions, writing more than 25.7 million prescriptions per year. Many are for prophylaxis in patients with prosthetic joint replacements; the American Dental Society states that "in general," prophylactic antibiotics are not recommended to prevent prosthetic joint infections. Orthopedic surgeons are concerned with the risk of implant infections following a dental procedure and, therefore, see high value and low risk in recommending prophylaxis. Patients are "stuck in the middle," with conflicting recommendations from orthopedic surgeons (OS) and dentists. Unnecessary prophylaxis and fear of lawsuits amongst private practice dentists and OS has not been addressed. We review The American Heart Association/American College of Cardiology, American Dental Association, and American Association of Orthopedic Surgeons' guidelines on dental antibiotic prophylaxis for the prevention of endocarditis and prosthetic joint infections. We provide experience on how to engage private-practice dentists and OS in dental stewardship using a community-based program.

Which Type of Empiric Antibiotic Therapy is Appropriate? A 20-Year Retrospective Study of Bloodstream Infections in Childhood Cancer

INTRODUCTION

Sufficient empirical antimicrobial therapy in febrile patients with cancer is challenging, owing to the limited arsenal of available antibiotics in an era of growing resistance. Because of the emergence of gram-negative bacteria resistant to ceftazidime and piperacillin, a combination antibiotic therapy was employed that uses meropenem combined with gentamicin and/or vancomycin if the patient further deteriorates.

METHODS

A retrospective cohort analysis was performed including all patients with catheter-associated bloodstream infections (BSIs) and treated for childhood cancer in a tertiary single centre between 1 January 2000 and 31 June 2018. We calculated the prevalence and the risk for BSIs and compared the in vitro susceptibility to various antimicrobial agents.

RESULTS

Of 653 patients with childhood cancer, 113 patients (17.3%) were identified with a total of 139 BSIs, most of them occurring in patients with leukaemia (n = 90, 64.7%) and were associated with gram-positive bacteria (60.5%). In our cohort, all BSIs with gram-negative bacteria exhibited in vitro susceptibility against meropenem alone without any signs of resistance development. The antibiotic coverage of our meropenem-based combination therapy was also highly effective for gram-positive and non-fermenting bacteria. Thus, BSI-related mortality in all 139 BSI episodes was 1.4%. Clostridium difficile infections (CDIs), as main adverse event of carbapenem usage, occurred in only 16 (2.5%) patients.

CONCLUSION

Our meropenem-based combination therapy showed sufficient empirical antibiotic coverage in the majority of BSIs (96.4%) and did not result in an increased rate of unwanted side effects or development of antibiotic resistance.

Engineered Phage Endolysin Eliminates Gardnerella Biofilm without Damaging Beneficial Bacteria in Bacterial Vaginosis Ex Vivo

Bacterial vaginosis is characterized by an imbalance of the vaginal microbiome and a characteristic biofilm formed on the vaginal epithelium, which is initiated and dominated by Gardnerella bacteria, and is frequently refractory to antibiotic treatment. We investigated endolysins of the type 1,4-beta-N-acetylmuramidase encoded on Gardnerella prophages as an alternative treatment. When recombinantly expressed, these proteins demonstrated strong bactericidal activity against four different Gardnerella species. By domain shuffling, we generated several engineered endolysins with 10-fold higher bactericidal activity than any wild-type enzyme. When tested against a panel of 20 Gardnerella strains, the most active endolysin, called PM-477, showed minimum inhibitory concentrations of 0.13–8 µg/mL. PM-477 had no effect on beneficial lactobacilli or other species of vaginal bacteria. Furthermore, the efficacy of PM-477 was tested by fluorescence in situ hybridization on vaginal samples of fifteen patients with either first time or recurring bacterial vaginosis. In thirteen cases, PM-477 killed the Gardnerella bacteria and physically dissolved the biofilms without affecting the remaining vaginal microbiome. The high selectivity and effectiveness in eliminating Gardnerella, both in cultures of isolated strains as well as in clinically derived samples of natural polymicrobial biofilms, makes PM-477 a promising alternative to antibiotics for the treatment of bacterial vaginosis, especially in patients with frequent recurrence.

Faecal transplantation and Clostridioides difficile infection

Faecal microbiota transplantation (FMT), known equally well as faecal transplantation or faecal bacteriotherapy, is the process of implanting the faecal suspension containing balanced microbiota from a healthy donor to the colon of a recipient patient. Excessive growth of Clostridioides difficile (C difficile) in the intestinal microbiota resulting from antibiotic consumption is currently a rising threat to public health. FMT is one of the most important, newer approaches to treating C difficile infections. Since C difficile is regarded as an opportunistic bacterium triggering disease in conditions of disturbed homeostasis of the intestinal microbiota, restoration of healthy intestinal microflora facilitates suppression of toxic strain of C difficile by anaerobic bacteria of normal intestinal microflora with concomitant cure. Nurses have important role in caring for patients after faecal transplantation.

Effect of the Short-Term Use of Fluoroquinolone and β-Lactam Antibiotics on Mouse Gut Microbiota

BACKGROUND

Antibiotics play an important role in the treatment of infectious diseases. However, the overuse of antibiotics increases the spread of drug-resistant bacteria and causes dysbiosis of the intestinal microbiota. Few studies have addressed the longitudinal effects of antibiotics on the microbiome and host immunity.

MATERIALS AND METHODS

In this study, the short-term effect of fluoroquinolone (levofloxacin) and β-lactam antibiotics (meropenem, cefoperazone/sulbactam, and aztreonam) on the gut microbiota of mice was evaluated by 16S rRNA gene sequencing. The susceptibility of Bifidobacterium longum, Lactobacillus lactis, Enterococcus faecium, and Clostridium butyricum to these antimicrobial agents was assessed using the disc diffusion method.

RESULTS

Our results showed that 4-day antibiotic exposure significantly reduced the alpha and beta diversity of gut bacteria and increased serum inflammatory cytokines, and these changes persisted long after antibiotic withdrawal and did not return to pre-treatment levels. Nonetheless, the bacterial community composition tended to return to pre-treatment levels after discontinuing treatment. The tested probiotic strains were resistant to aztreonam but were sensitive to meropenem and cefoperazone/sulbactam.

CONCLUSION

Short-term antibiotic treatment led to significant changes in the intestinal flora with a tendency to recover. The antibiotics had different effects on the intestinal microbial community and probiotic strains. This study provides guidance for the concomitant use of probiotics and antibiotics, and the results emphasize the importance of using broad-spectrum antibiotics responsibly to prevent the long-term disruption of the native microbiota.