Effectiveness of Oral Vancomycin for Prevention of Healthcare Facility-Onset Clostridioides difficile Infection in Targeted Patients During Systemic Antibiotic Exposure

An Open-Label, Randomized Trial Comparing Fidaxomicin With Oral Vancomycin for the Treatment of Clostridioides difficile Infection in Hospitalized Patients Receiving Concomitant Antibiotics for Concurrent Infections

BACKGROUND

Recurrent Clostridioides difficile infection (rCDI) occurs frequently, and concomitant antibiotic (CA) during the initial episode for treatment of non-CDI is a major risk factor. We sought to address the comparative efficacy of fidaxomicin versus vancomycin in the setting of CA during the initial CDI episode.

METHODS

We conducted a randomized, controlled, open-label trial at 2 hospitals in Ann Arbor, Michigan. We consecutively consented and enrolled hospitalized patients ≥18 years old with diarrhea, a positive test for C. difficile, and ≥1 qualifying CA. Complicated CDI, CDI treatment for >24 hours prior to enrollment, and planned long-term (>12 weeks) CA use were notable exclusions. Clinical cure was defined as resolution of diarrhea for 2 consecutive days maintained until 2 days after therapy, and rCDI as recurrent diarrhea with positive testing ≤30 days after initial treatment. Patients were randomized to fidaxomicin or vancomycin.

RESULTS

Baseline characteristics were similar in the 2 groups of 144 patients. Rates of clinical cure (73% vs 62.9%, P = .195) and rCDI (3.3% vs 4.0%; P > .99) were similar for fidaxomicin and vancomycin in the intention-to-treat and per-protocol cohorts, respectively. Only 4 patients developed rCDI.

CONCLUSIONS

In this study of patients with CDI receiving CA, a numerically higher proportion were cured with fidaxomicin versus vancomycin, but this result did not reach statistical significance. Overall recurrence was lower than anticipated in both arms compared with previous studies that did not extend duration of CDI treatment during CA.

CLINICAL TRIALS REGISTRATION

www.clinicaltrials.gov (NCT02692651).

An epidemiological surveillance study (2021-2022): detection of a high diversity of Clostridioides difficile isolates in one tertiary hospital in Chongqing, Southwest China

BACKGROUND

Clostridioides difficile is a bacterium that causes antibiotic-associated infectious diarrhea and pseudomembranous enterocolitis. The impact of C. difficile infection (CDI) in China has gained significant attention in recent years. However, little epidemiological data are available from Chongqing, a city located in Southwest China. This study aimed to investigate the epidemiological pattern of CDI and explore the drug resistance of C. difficile isolates in Chongqing.

METHODS

A case-control study was conducted to investigate the clinical infection characteristics and susceptibility factors of C. difficile. The features of the C. difficile isolates were evaluated by testing for toxin genes and using multi-locus sequence typing (MLST). The susceptibility of strains to nine antibiotics was determined using agar dilution technique.

RESULTS

Out of 2084 diarrhea patients, 90 were tested positive for the isolation of toxigenic C. difficile strains, resulting in a CDI prevalence rate of 4.32%. Tetracycline, cephalosporins, hepatobiliary disease, and gastrointestinal disorders were identified as independent risk factors for CDI incidence. The 90 strains were classified into 21 sequence types (ST), with ST3 being the most frequent (n = 25, 27.78%), followed by ST2 (n = 10, 11.11%) and ST37 (n = 9, 10%). Three different toxin types were identified: 69 (76.67%) were A+B+CDT-, 12 (13.33%) were A-B+CDT-, and 9 (10%) were A+B+CDT+. Although substantial resistance to erythromycin (73.33%), moxifloxacin (62.22%), and clindamycin (82.22%), none of the isolates exhibited resistance to vancomycin, tigecycline, or metronidazole. Furthermore, different toxin types displayed varying anti-microbial characteristics.

CONCLUSIONS

The strains identified in Chongqing, Southwest China, exhibited high genetic diversity. Enhance full awareness of high-risk patients with HA-CDI infection, particularly those with gastrointestinal and hepatocellular diseases, and emphasize caution in the use of tetracycline and capecitabine. These findings suggest that a potential epidemic of CDI may occur in the future, emphasizing the need for timely monitoring.

Evaluation of the effectiveness and safety of oral vancomycin versus placebo in the prevention of recurrence of Clostridioides difficile infection in patients under systemic antibiotic therapy: a phase III, randomised, double-blind clinical trial

INTRODUCTION

Clostridioides difficile infection (CDI) is the most prevalent cause of nosocomial bacterial diarrhoea and it is strongly associated with antibiotic use. The recurrence of CDI is a growing medical problem. Data from real-life studies and one open label randomised clinical trial (RCT) suggest that secondary prophylaxis with oral vancomycin (SPV) during subsequent courses of systemic antibiotics is a promising approach for reducing the risk of CDI recurrence. Our aim is to confirm the role of SPV through a double-blind RCT.

METHODS AND ANALYSIS

We will perform a phase III, multicentre, placebo-controlled RCT (PREVAN trial) in a 2:1 ratio in favour of SPV (experimental treatment), in four tertiary care hospitals in Spain. Adult patients (≥18 years) with a previous history of CDI in the previous 180 days and with requirement for hospitalisation and systemic antibiotic therapy will be randomly allocated to receive either 125 mg of oral vancomycin or placebo every 6 hours for 10 days. Patients will be followed for 60 days after the end of treatment to verify a reduction in the rate of CDI recurrence in the experimental group. We assume a recurrence rate of 5% in the experimental group versus 25% in the placebo group. Accepting an alpha risk of 0.05 and a beta risk of 0.2 in a two-sided test, 104 subjects will be required in total (68 assigned to the SPV group and 34 to the placebo group).

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Ethic Committee for Research with medicinal products of the University Hospital '12 de Octubre' (AC069/18) and from the Spanish Medicines and Healthcare Product Regulatory Agency (AEMPS, AC069/18), which is valid for all participating centres under existing Spanish legislation. The results will be presented at international meetings and will be made available to patients and funders.

TRIAL REGISTRATION NUMBER

NCT05320068.

Microbiome-Related and Infection Control Approaches to Primary and Secondary Prevention of Clostridioides difficile Infections

Clostridioides difficile infections (CDIs) have decreased in the past years, but since 2021, some hospitals have reported an increase in CDI rates. CDI remains a global concern and has been identified as an urgent threat to healthcare. Although multiple treatment options are available, prevention strategies are more limited. As CDI is an opportunistic infection that arises after the normally protective microbiome has been disrupted, preventive measures aimed at restoring the microbiome have been tested. Our aim is to update the present knowledge on these various preventive strategies published in the past five years (2018-2023) to guide clinicians and healthcare systems on how to best prevent CDI. A literature search was conducted using databases (PubMed, Google Scholar, and clinicaltrials.gov) for phase 2-3 clinical trials for the primary or secondary prevention of CDI and microbiome and probiotics. As the main factor for Clostridium difficile infections is the disruption of the normally protective intestinal microbiome, strategies aimed at restoring the microbiome seem most rational. Some strains of probiotics, the use of fecal microbial therapy, and live biotherapeutic products offer promise to fill this niche; although, more large randomized controlled trials are needed that document the shifts in the microbiome population.

The need for evolution in the management of febrile neutropenia in pediatric cancer: TRIIO KIDS update

New treatments have increased the life expectancy of pediatric patients diagnosed with malignant hematological diseases, often at the cost of protracting their immunocompromised state in the form of prolonged neutropenia. This neutropenic state favors the development of bacterial and fungal infections. Moreover, recent years have seen a series of changes in the epidemiology of fungal and Clostridium infections. These changes necessitate adaptations to the management of pediatric patients with febrile neutropenia, who are at risk of further increases in already high rates of morbidity and mortality. This article discusses the current bases for the management of febrile neutropenia and associated emerging fungal infections, as well as the epidemiology, diagnosis, and treatment of Clostridioides difficile in pediatric patients diagnosed with malignant hematological diseases.

Comparison of the Risk of Recurrent Clostridioides Difficile Infections Among Patients in 2018 Versus 2013

Among persons with an initial Clostridioides difficile infection (CDI) across 10 US sites in 2018 compared with 2013, 18.3% versus 21.1% had ≥1 recurrent CDI (rCDI) within 180 days. We observed a 16% lower adjusted risk of rCDI in 2018 versus 2013 (P < .0001).

Educational Impact of #IDJClub, a Twitter-Based Infectious Diseases Journal Club

BACKGROUND

Journal clubs have been an enduring mainstay of medical education, and hosting these on social media platforms can expand accessibility and engagement. We describe the creation and impact of #IDJClub, an infectious diseases (ID) Twitter journal club.

METHODS

We launched #IDJClub in October 2019. Using the account @IDJClub, an ID physician leads a 1-hour open-access Twitter discussion of a recent publication. All participants use the hashtag #IDJClub. Sessions started monthly, but increased due to demand during the coronavirus disease 2019 (COVID-19) pandemic. We used Symplur 's Healthcare Hashtag project to track engagement of #IDJClub per 60-minute discussion plus the following 30 minutes to capture ongoing conversations. We also conducted an online anonymous survey using Likert scales and open-ended questions to assess educational impact.

RESULTS

In its first 20 months, 31 journal clubs were held, with medians of 42 (interquartile range [IQR], 28.5-60) participants and 312 (IQR, 205-427.5) tweets per session. 134 participants completed the survey, of whom 39% were ID physicians, 19% pharmacists, 13% ID fellows, and 10% medical residents. Most agreed or strongly agreed that #IDJClub provided clinically useful knowledge (95%), increased personal confidence in independent literature appraisal (72%), and was more educational than traditional journal clubs (72%). The format addressed several barriers to traditional journal club participation such as lack of access, subject experts, and time.

CONCLUSIONS

#IDJClub is an effective virtual journal club, providing an engaging, open-access tool for critical literature appraisal that overcomes several barriers to traditional journal club participations while fostering connectedness within the global ID community.

Risk factors of first recurrence of Clostridioides difficile infection

OBJECTIVES

Clostridioides difficile infection (CDI) often recurs. Approximately 25% of patients have recurrences after the initial treatment, and patients who have relapsed once are more likely to relapse. We aimed to identify the risk factors for initial CDI recurrence.

METHODS

We performed a retrospective survey of patient backgrounds and treatment-related factors. Risk factors were analyzed using single and multiple logistic regression analyses.

RESULTS

A total of 134 patients were included in the study. Prophylactic probiotic use and nasogastric tube feeding were independent risk factors for the initial recurrence of CDI. Patients using prophylactic probiotics had significantly higher recurrence rates than those not using prophylactic probiotics.

CONCLUSION

Prophylactic probiotic use and nasogastric tube placement may be risk factors for the initial recurrence of CDI. It is noteworthy that CDI that occurs during the use of prophylactic probiotics may be prone to recurrence.

Oral Vancomycin Prophylaxis for Primary and Secondary Prevention of Clostridioides difficile Infection in Patients Treated with Systemic Antibiotic Therapy: A Systematic Review, Meta-Analysis and Trial Sequential Analysis

Background: Clostridioides difficile infection (CDI) is associated with substantial morbidity and mortality as well as high propensity of recurrence. Systemic antibiotic therapy (SAT) represents the top inciting factor of CDI, both primary and recurrent (rCDI). Among the many strategies aimed to prevent CDI in high-risk subjects undergoing SAT, oral vancomycin prophylaxis (OVP) appears promising under a cost-effectiveness perspective. Methods: A systematic review with meta-analysis and trial sequential analysis (TSA) of studies assessing the efficacy and the safety of OVP to prevent primary CDI and rCDI in persons undergoing SAT was carried out. PubMed and EMBASE were searched until 30 September 2021. The protocol was pre-registered on PROSPERO (CRD42019145543). Results: Eleven studies met the inclusion criteria, only one being a randomized controlled trial (RCT). Overall, 929 subjects received OVP and 2011 represented the comparator group (no active prophylaxis). OVP exerted a strong protective effect for CDI occurrence: odds ratio 0.14, 95% confidence interval 0.04–0.38. Moderate heterogeneity was observed: I² 54%. This effect was confirmed throughout several subgroup analyses, including prevention of primary CDI versus rCDI. TSA results pointed at the conclusive nature of the evidence. Results were robust to a variety of sensitivity and quantitative bias analyses, although the underlying evidence was deemed as low quality. No differences between the two groups were highlighted regarding the onset of vancomycin-resistant Enterococcus infections. Conclusions: OVP appears to be an efficacious option for prevention of CDI in high-risk subjects undergoing SAT. Nevertheless, additional data from RCTs are needed to establish OVP as good clinical practice and define optimal dosage and duration.

European Society of Clinical Microbiology and Infectious Diseases: 2021 update on the treatment guidance document for Clostridioides difficile infection in adults

SCOPE

In 2009, the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) published the first treatment guidance document for Clostridioides difficile infection (CDI). This document was updated in 2014. The growing literature on CDI antimicrobial treatment and novel treatment approaches, such as faecal microbiota transplantation (FMT) and toxin-binding monoclonal antibodies, prompted the ESCMID study group on C. difficile (ESGCD) to update the 2014 treatment guidance document for CDI in adults.

METHODS AND QUESTIONS

Key questions on CDI treatment were formulated by the guideline committee and included: What is the best treatment for initial, severe, severe-complicated, refractory, recurrent and multiple recurrent CDI? What is the best treatment when no oral therapy is possible? Can prognostic factors identify patients at risk for severe and recurrent CDI and is there a place for CDI prophylaxis? Outcome measures for treatment strategy were: clinical cure, recurrence and sustained cure. For studies on surgical interventions and severe-complicated CDI the outcome was mortality. Appraisal of available literature and drafting of recommendations was performed by the guideline drafting group. The total body of evidence for the recommendations on CDI treatment consists of the literature described in the previous guidelines, supplemented with a systematic literature search on randomized clinical trials and observational studies from 2012 and onwards. The Grades of Recommendation Assessment, Development and Evaluation (GRADE) system was used to grade the strength of our recommendations and the quality of the evidence. The guideline committee was invited to comment on the recommendations. The guideline draft was sent to external experts and a patients' representative for review. Full ESCMID endorsement was obtained after a public consultation procedure.

RECOMMENDATIONS

Important changes compared with previous guideline include but are not limited to: metronidazole is no longer recommended for treatment of CDI when fidaxomicin or vancomycin are available, fidaxomicin is the preferred agent for treatment of initial CDI and the first recurrence of CDI when available and feasible, FMT or bezlotoxumab in addition to standard of care antibiotics (SoC) are preferred for treatment of a second or further recurrence of CDI, bezlotoxumab in addition to SoC is recommended for the first recurrence of CDI when fidaxomicin was used to manage the initial CDI episode, and bezlotoxumab is considered as an ancillary treatment to vancomycin for a CDI episode with high risk of recurrence when fidaxomicin is not available. Contrary to the previous guideline, in the current guideline emphasis is placed on risk for recurrence as a factor that determines treatment strategy for the individual patient, rather than the disease severity.

Epidemiology, Diagnosis, and Treatment of Clostridioides difficile Infection in Immunocompromised Children

Clostridioides difficile infection is very common in immunocompromised children. Management is confounded by frequent asymptomatic colonization, multiple alternative etiologies for gastrointestinal symptoms, and high rates of relapse. Important considerations include indications for testing, appropriate choice of diagnostic tests, antibiotic therapy for initial and subsequent episodes, and primary and secondary prevention.

Clostridioides difficile and Vancomycin-Resistant Enterococci in COVID-19 Patients with Severe Pneumonia

Broad-spectrum antibiotics administered to patients with severe COVID-19 pneumonia pose a risk of infection caused by Clostridioides difficile. This risk is reduced mainly by strict hygiene measures and early de-escalation of antibiotic therapy. Recently, oral vancomycin prophylaxis (OVP) has also been discussed. This retrospective study aimed to assess the prevalence of C. difficile in critical COVID-19 patients staying in an intensive care unit of a tertiary hospital department of anesthesiology, resuscitation, and intensive care from November 2020 to May 2021 and the rates of vancomycin-resistant enterococci (VRE) after the introduction of OVP and to compare the data with those from controls in the pre-pandemic period (November 2018 to May 2019). During the COVID-19 pandemic, there was a significant increase in toxigenic C. difficile rates to 12.4% of patients, as compared with 1.6% in controls. The peak rates were noted in February 2021 (25% of patients), immediately followed by initiation of OVP, changes to hygiene precautions, and more rapid de-escalation of antibiotic therapy. Subsequently, toxigenic C. difficile detection rates started to fall. There was a nonsignificant increase in VRE detected in non-gastrointestinal tract samples to 8.9% in the COVID-19 group, as compared to 5.3% in the control group. Molecular analysis confirmed mainly clonal spread of VRE.

Trends in Healthcare Facility-Onset Clostridioides difficile Infection and the Impact of Testing Schemes in an Acute Care Hospital System in New York City, 2016-2019

BACKGROUND

Healthcare facility-onset Clostridioides difficile infection is associated with adverse clinical outcomes and hospital reimbursement. A four-year review involving eleven hospitals of the NYC Health + Hospital system was undertaken.

METHODS

From 2016-2019, infection rates and standardized infection ratios (SIRs) were gathered from National Healthcare Safety Network. The C. difficile testing scheme at each facility was recorded.

RESULTS

For the eleven hospitals, declines in rates of C. difficile infection and SIRs were documented. However, this decline was driven by two hospitals that had high rates of infection in 2016; for the remaining nine hospitals, rates of infection and SIRs were at a plateau. Most hospitals used a testing scheme that fell into the nucleic acid amplification test (NAAT) category for SIR risk adjustment. Hospitals that used the algorithm glutamate dehydrogenase (GDH) and toxin A/B immunoassay (EIA) followed by NAAT for discrepant results had significantly lower rates of C. difficile infection but similar SIRs.

CONCLUSIONS

For most hospitals in this system, rates of C. difficile remained level. Within the NAAT test categories, SIRs may not correlate with infection rates. Given the controversies regarding testing and calculation of SIRs, alternatives to C. difficile infection should be sought as a hospital quality measurement.

Oral Vancomycin as Secondary Prophylaxis for Clostridioides difficile Infection

OBJECTIVES

Secondary oral vancomycin prophylaxis (OVP) has been used in adults with a history of Clostridioides difficile infection (CDI) while receiving systemic antibiotics to prevent CDI recurrence. However, this practice has not been studied in pediatric patients. The objective of this study was to assess the utility of secondary OVP in pediatric patients with previous CDI who received subsequent antibiotic exposure.

METHODS

A multicampus, retrospective cohort evaluation was conducted among patients aged ≤18 years with any history of clinical CDI and receiving systemic antibiotics in a subsequent encounter from 2013-2019. Patients who received concomitant OVP with antibiotics were compared with unexposed patients. The primary outcome was CDI recurrence within 8 weeks after antibiotic exposure. Infection with vancomycin-resistant enterococci and risk factors for CDI recurrence were assessed.

RESULTS

A total of 148 patients were screened, of which 30 and 44 patients received OVP and no OVP, respectively. Patients who received OVP had greater antibiotic use and hospital lengths of stay. The incidence of CDI recurrence within 8 weeks of antibiotic exposure was significantly lower in patients who received OVP (3% vs 25%; P = .02) despite this group having notably more risk factors for recurrence. There were no vancomycin-resistant enterococci infections in any patients within either group. After adjustment in a multivariable analysis, secondary OVP was associated with less risk of recurrence (odds ratio, 0.10; 95% confidence interval, 0.01-0.86; P = .04).

CONCLUSIONS

Secondary OVP while receiving systemic antibiotics reduces the risk of recurrent CDI in pediatric patients with a history of CDI.

How to: prophylactic interventions for prevention of Clostridioides difficile infection

BACKGROUND

Clostridioides difficile infection (CDI) remains the leading cause of healthcare-associated diarrhoea, despite existing guidelines for infection control measures and antimicrobial stewardship. The high associated health and economic burden of CDI calls for novel strategies to prevent the development and spread of CDI in susceptible patients.

OBJECTIVES

We aim to review CDI prophylactic treatment strategies and their implementation in clinical practice.

SOURCES

We searched PubMed, Embase, Emcare, Web of Science, and the COCHRANE Library databases to identify prophylactic interventions aimed at prevention of CDI. The search was restricted to articles published in English since 2012.

CONTENT

A toxin-based vaccine candidate is currently being investigated in a phase III clinical trial. However, a recent attempt to develop a toxin-based vaccine has failed. Conventional probiotics have not yet proved to be an effective strategy for prevention of CDI. New promising microbiota-based interventions that bind and inactivate concomitantly administered antibiotics, such as ribaxamase and DAV-132, have been developed. Prophylaxis of CDI with C. difficile antibiotics should not be performed routinely and should be considered only for secondary prophylaxis in very selected patients who are at the highest imminent risk for recurrent CDI (R-CDI) after a thorough evaluation. Faecal microbiota transplantation (FMT) has proved to be a very effective treatment for patients with multiple recurrences. Bezlotoxumab provides protection against R-CDI, mainly in patients with primary episodes and a high risk of relapse.

IMPLICATIONS

There are no proven effective, evidenced-based prophylaxis options for primary CDI. As for secondary prevention, FMT is considered the option of choice in patients with multiple recurrences. Bezlotoxumab can be added to standard treatment for patients at high risk for R-CDI. The most promising strategies are those aimed at reducing changes in intestinal microbiota and development of a new effective non-toxin-based vaccine.

ACG Clinical Guidelines: Prevention, Diagnosis, and Treatment of Clostridioides difficile Infections

Clostridioides difficile infection occurs when the bacterium produces toxin that causes diarrhea and inflammation of the colon. These guidelines indicate the preferred approach to the management of adults with C. difficile infection and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation process. In instances where the evidence was not appropriate for Grading of Recommendations Assessment, Development, and Evaluation but there was consensus of significant clinical merit, key concept statements were developed using expert consensus. These guidelines are meant to be broadly applicable and should be viewed as the preferred, but not the only, approach to clinical scenarios.

Evaluation of a risk assessment model to predict infection with healthcare facility-onset Clostridioides difficile

Disclaimer

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

Purpose

We evaluated a previously published risk model (Novant model) to identify patients at risk for healthcare facility–onset Clostridioides difficile infection (HCFO-CDI) at 2 hospitals within a large health system and compared its predictive value to that of a new model developed based on local findings.

Methods

We conducted a retrospective case-control study including adult patients admitted from July 1, 2016, to July 1, 2018. Patients with HCFO-CDI who received systemic antibiotics were included as cases and were matched 1 to 1 with controls (who received systemic antibiotics without developing HCFO-CDI). We extracted chart data on patient risk factors for CDI, including those identified in prior studies and those included in the Novant model. We applied the Novant model to our patient population to assess the model’s utility and generated a local model using logistic regression–based prediction scores. A receiver operating characteristic area under the curve (ROC-AUC) score was determined for each model.

Results

We included 362 patients, with 161 controls and 161 cases. The Novant model had a ROC-AUC of 0.62 in our population. Our local model using risk factors identifiable at hospital admission included hospitalization within 90 days of admission (adjusted odds ratio [OR], 3.52; 95% confidence interval [CI], 2.06-6.04), hematologic malignancy (adjusted OR, 12.87; 95% CI, 3.70-44.80), and solid tumor malignancy (adjusted OR, 4.76; 95% CI, 1.27-17.80) as HCFO-CDI predictors and had a ROC-AUC score of 0.74.

Conclusion

The Novant model evaluating risk factors identifiable at admission poorly predicted HCFO-CDI in our population, while our local model was a fair predictor. These findings highlight the need for institutions to review local risk factors to adjust modeling for their patient population.

Could simulation methods solve the curse of sparse data within clinical studies of antibiotic resistance?

Infectious disease (ID) physicians and ID pharmacists commonly confront therapeutic questions relating to antibiotic resistance. Randomized controlled trial data are few and meta-analytic-based approaches to develop the evidence-base from several small studies that might relate to an antibiotic resistance question are not simple. The overriding challenge is the sparsity of data which is problematic for traditional frequentist methods, being the paradigm underlying the derivation of ‘P value’ inferential statistics. In other sparse data contexts, simulation methods enable answers to key questions that are meaningful, quantitative and potentially relevant. How these simulation methods ‘work’ and how Bayesian-based methods, being not ‘P value based’, can facilitate simulation are reviewed. These methods are becoming increasingly accessible. This review highlights why sparse data is less of an issue within Bayesian versus frequentist paradigms. A fictional pharmacokinetic study with sparse data illustrates a simplistic application of Bayesian and simulation methods to antibiotic dosing. Whether within epidemiological projections or clinical studies, simulation methods are likely to play an increasing role in antimicrobial resistance research within both hospital and community studies of either rare infectious disease or infections within specific population groups.

Efficacy of oral vancomycin prophylaxis for prevention of Clostridioides difficile infection: a systematic review and meta-analysis

BACKGROUND

Prevention of recurrent Clostridioides difficile infection (CDI) is a challenge in clinical practice, particularly in patients who need systemic antimicrobial therapy. We aimed to evaluate the role of oral vancomycin prophylaxis (OVP) in prevention of primary or future CDI in patients on systemic antimicrobial therapy.

METHODS

A systematic search of MEDLINE, Embase, and Web of Science was performed from 2000 to January 2020. We included case-control or cohort studies that included patients on systemic antimicrobial therapy who did or did not receive oral vancomycin prophylaxis (OVP) and were evaluated for development of CDI. Odds ratio (OR) estimates with 95% confidence intervals (CI) were calculated.

RESULTS

Four studies including 1352 patients evaluated OVP for primary CDI prevention, with CDI occurring in 29/402 patients on OVP (7.4%) compared with 10.4% (99/950) without OVP. Meta-analysis revealed no significant decrease in risk of CDI in patients who received OVP (OR, 0.18; 95% CI, 0.03-1.03; p = 0.06). There was significant heterogeneity with I 2 = 76%. Ten studies including 9258 patients evaluated OVP for secondary CDI prevention. Future CDI occurred in 91/713 patients on OVP (13.3%) compared with 21.9% (1875/8545) who did not receive OVP. Meta-analysis revealed a statistically significant decreased risk of future CDI (OR, 0.34; 95% CI, 0.20-0.59; p < 0.00001). Significant heterogeneity was seen with I 2 = 59%.

DISCUSSION

Based on observational data, OVP appears to decrease the risk of future CDI in patients with prior CDI who require systemic antimicrobial therapy. However, OVP was not effective for primary prevention of CDI.

Randomized Controlled Trial of Oral Vancomycin Treatment in Clostridioides difficile-Colonized Patients

A gold standard diagnostic for Clostridioides difficile infection (CDI) does not exist. An area of controversy is how to manage patients whose stool tests positive by nucleic acid amplification tests but negative by toxin enzyme immunoassay.

Clostridioides difficile infection (CDI) is most commonly diagnosed using nucleic acid amplification tests (NAAT); the low positive predictive value of these assays results in patients colonized with C. difficile unnecessarily receiving CDI treatment antibiotics. The risks and benefits of antibiotic treatment in individuals with such cases are unknown. Fecal samples of NAAT-positive, toxin enzyme immunoassay (EIA)-negative patients were collected before, during, and after randomization to vancomycin (n = 8) or placebo (n = 7). C. difficile and antibiotic-resistant organisms (AROs) were selectively cultured from fecal and environmental samples. Shotgun metagenomics and comparative isolate genomics were used to understand the impact of oral vancomycin on the microbiome and environmental contamination. Overall, 80% of placebo patients and 71% of vancomycin patients were colonized with C. difficile posttreatment. One person randomized to placebo subsequently received treatment for CDI. In the vancomycin-treated group, beta-diversity (P = 0.0059) and macrolide-lincosamide-streptogramin (MLS) resistance genes (P = 0.037) increased after treatment; C. difficile and vancomycin-resistant enterococci (VRE) environmental contamination was found in 53% of patients and 26% of patients, respectively. We found that vancomycin alters the gut microbiota, does not permanently clear C. difficile, and is associated with VRE colonization/environmental contamination. (This study has been registered at ClinicalTrials.gov under registration no. NCT03388268.)

IMPORTANCE A gold standard diagnostic for Clostridioides difficile infection (CDI) does not exist. An area of controversy is how to manage patients whose stool tests positive by nucleic acid amplification tests but negative by toxin enzyme immunoassay. Existing data suggest most of these patients do not have CDI, but most are treated with oral vancomycin. Potential benefits to treatment include a decreased risk for adverse outcomes if the patient does have CDI and the potential to decrease C. difficile shedding/transmission. However, oral vancomycin perturbs the intestinal microbiota and promotes antibiotic-resistant organism colonization/transmission. We conducted a double-blinded randomized controlled trial to assess the risk-benefit of oral vancomycin treatment in this population. Oral vancomycin did not result in long-term clearance of C. difficile, perturbed the microbiota, and was associated with colonization/shedding of vancomycin-resistant enterococci. This work underscores the need to better understand this population of patients in the context of C. difficile/ARO-related outcomes and transmission.

Critical Care Management of the Patient with Clostridioides difficile

OBJECTIVES

To review published clinical evidence on management of Clostridioides difficile infection in critically ill patients.

DATA SOURCES

We obtained relevant studies from a PubMed literature review and bibliographies of reviewed articles.

STUDY SELECTION

We selected English-language studies addressing aspects of C. difficile infection relevant to critical care clinicians including epidemiology, risk factors, diagnosis, treatment, and prevention, with a focus on high-quality clinical evidence.

DATA EXTRACTION

We reviewed potentially relevant studies and abstracted information on study design, methods, patient selection, and results of relevant studies. This is a synthetic (i.e., not systematic) review.

DATA SYNTHESIS

C. difficile infection is the most common healthcare-associated infection in the United States. Antibiotics are the most significant C. difficile infection risk factor, and among antibiotics, cephalosporins, clindamycin, carbapenems, fluoroquinolones, and piperacillin-tazobactam confer the highest risk. Age, diabetes mellitus, inflammatory bowel disease, and end-stage renal disease are risk factors for C. difficile infection development and mortality. C. difficile infection diagnosis is based on testing appropriately selected patients with diarrhea or on clinical suspicion for patients with ileus. Patients with fulminant disease (C. difficile infection with hypotension, shock, ileus, or megacolon) should be treated with oral vancomycin and IV metronidazole, as well as rectal vancomycin in case of ileus. Patients who do not respond to initial therapy should be considered for fecal microbiota transplant or surgery. Proper infection prevention practices decrease C. difficile infection risk.

CONCLUSIONS

Strong clinical evidence supports limiting antibiotics when possible to decrease C. difficile infection risk. For patients with fulminant C. difficile infection, oral vancomycin reduces mortality, and adjunctive therapies (including IV metronidazole) and interventions (including fecal microbiota transplant) may benefit select patients. Several important questions remain regarding fulminant C. difficile infection management, including which patients benefit from fecal microbiota transplant or surgery.

Extraintestinal Clostridioides difficile infection

Clostridioides (Clostridium) difficile is the major cause of healthcare antibiotic-associated diarrhoea. However, extra-intestinal manifestations of Clostridioides (Clostridium) difficile infection (CDI) (including bacteremia and tissue infection) are extremely rare. We report a case of extraintestinal CDI after surgery. The isolate of C. difficile was not the PCR ribotype 027. However, this isolate produced toxins A and B. The patient underwent a follow-up examination 30 days after discharge, which showed complete recovery. This case report adds to existing knowledge of CDI.

Universal molecular Clostridioides difficile screening and overtreatment in solid organ transplant recipients

BACKGROUND

Screening for Clostridioides difficile (CD) colonization can be performed using molecular testing to identify the presence of microbial DNA of the toxin gene. Colonization rates for hospitalized patients are as high as 20% and may be considerably higher in solid organ transplant (SOT) recipients. Treatment for CD should be based on clinical disease and not colonization, yet clinicians may misinterpret a positive CD screen resulting in overtreatment.

OBJECTIVES

The objective of this analysis is to determine how often positive CD screens resulted in inappropriate treatment with oral vancomycin.

METHODS

Clostridioides difficile screens were performed using the Xpert C difficile assay (Cepheid), a nucleic acid amplification testing method utilizing polymerase chain reaction (PCR), on peri-rectal swabs for newly admitted patients. This was a single-center cohort study of adult patients with CD screens hospitalized between July 2015 and November 2018. The primary outcome was the rate of inappropriate oral vancomycin treatment in all patients and in SOT recipients, defined as therapy in the absence of diarrhea.

RESULTS

Of the 47 076 total CD screens reviewed, 1,921 were positive. In the SOT cohort, 58 of 329 screens were positive (4.1% vs 17.9%, P < .01). Of all patients with a positive CD screen, 20.1% (386/1921) were treated with oral vancomycin within 48 hours of swab collection. In the SOT cohort, 39.6% (23/58) with positive CD screens were treated with oral vancomycin within 48 hours. Of the SOT patients who received oral vancomycin, 39% (9/23) did not have true CD infection.

CONCLUSION

Solid organ transplant recipients were more likely to have CD colonization detected by peri-rectal screening than the general inpatient population. SOT and non-SOT patients were treated with oral vancomycin at similar rates in response to the positive screen. Nearly half of the oral vancomycin use in SOT recipients was likely overtreatment, but this finding is limited by the low number of patients in this cohort.

Oral vancomycin prophylaxis for the prevention of Clostridium difficile infection: A systematic review and meta-analysis

OBJECTIVE

Recently, oral vancomycin prophylaxis (OVP) has been suggested for the prevention of Clostridium difficile infection (CDI). We conducted a systematic review and meta-analysis to investigate the efficacy and safety of this approach.

DESIGN

Systematic review and meta-analysis.

METHODS

We conducted a computerized search of MEDLINE, EMBASE, and Cochrane databases from inception to March 2019 for publications investigating OVP for CDI prevention. Results were screened for eligibility. Relevant data were extracted and analyzed. Publication bias was assessed using the Egger test.

RESULTS

Ultimately, 8 retrospective studies and 1 prospective study examining 2174 patients, published between 2016 and 2019 were included in the review. OVP was associated with decreased CDI (odds ratio, 0.263; 95% confidence interval, 0.13-0.52) with considerable heterogeneity (I2 = 61%). Meta-regression showed that total daily dose of OVP correlated with CDI, explaining 100% of heterogeneity between studies. Furthermore, 3 studies evaluated the risk of vancomycin-resistant enterococci (VRE) infection after OVP and found no significant increase.

CONCLUSION

Our results suggest that OVP might decrease CDI rates in at-risk populations, although this conclusion should be interpreted with caution. Higher daily doses of OVP might increase CDI. Although the use of OVP in high-risk patients may reduce CDI, this suggestion has yet to be validated by prospective blinded randomized controlled trials.