Update on microbiota-derived therapies for recurrent Clostridioides difficile infections

BACKGROUND

Faecal microbiota transplantation (FMT) is the standard treatment for patients with multiple recurrent Clostridioides difficile infection (rCDI). Recently, new commercially developed human microbiota-derived medicinal products have been evaluated and Food and Drug Administration-approved with considerable differences in terms of composition, administration, and targeted populations.

OBJECTIVES

To review available data on the different microbiota-derived treatments at the stage of advanced clinical evaluation and research in rCDI in comparison with FMT.

SOURCES

Phase II or III trials evaluating a microbiota-derived medicinal product to prevent rCDI.

CONTENT

Two commercial microbiota-derived medicinal products are approved by the Food and Drug Administration: Rebyota (RBX2660 Ferring Pharmaceuticals, marketed in the United States) and VOWST (SER-109 -Seres Therapeutics, marketed in the United States), whereas VE303 (Vedanta Biosciences Inc) will be studied in phase III trial. RBX2660 and SER-109 are based on the processing of stools from healthy donors, whereas VE303 consists of a defined bacterial consortium originating from human stools and produced from clonal cell banks. All have proven efficacy to prevent rCDI compared with placebo in patients considered at high risk of recurrence. However, the heterogeneity of the inclusion criteria, and the time between each episode and CDI diagnostics makes direct comparison between trials difficult. The differences regarding the risk of recurrence between the treatment and placebo arms were lower than previously described for FMT (FMT: Δ = 50.5%; RBX2660-phase III: Δ = 13.1%; SER-109-phase III: Δ = 28%; high-dose VE303-phase-II: Δ = 31.7%). All treatments presented a good overall safety profile with mainly mild gastrointestinal symptoms.

IMPLICATIONS

Stool-derived products and bacterial consortia need to be clearly distinguished in terms of product characterization and their associated risks with specific long-term post-marketing evaluation similar to registries used for FMT. Their place in the therapeutic strategy for patients with rCDI requires further studies to determine the most appropriate patient population and administration route to prevent rCDI.

Heterogeneity in practices to reduce the risk of transmission of Clostridioides difficile in healthcare settings: a survey of ESCMID Study Group for Clostridioides difficile (ESGCD) members

Clostridioides difficile is a leading cause of healthcare-associated infections. The main objective was to assess the current landscape of CDI infection prevention and control (IPC) practices. An anonymous survey of IPC practices for CDI was conducted between July 25 and October 31, 2022. Precautions for symptomatic patients were applicable for 75.9% and were discontinued 48 h minimum after the resolution of diarrhea for 40.7% of respondents. Daily cleaning of CDI patients' rooms was reported by 23 (42.6%). There was unexpected heterogeneity in IPC practices regarding the hospital management of CDI.

Ribotypes and New Virulent Strains Across Europe

Clostridioides (formerly Clostridium) difficile is a major bacterial cause of post-antibiotic diarrhoea. The epidemiology of C. difficile infections (CDIs) has dramatically changed since the early 2000s, with an increasing incidence and severity across Europe. This trend is partly due to the emergence and rapid worldwide spread of the hypervirulent and epidemic PCR ribotype 027. Profiles of patients with CDI have also evolved, with description of community-acquired (CA) infections in patients with no traditional risk factors for CDI. However, epidemiological studies indicated that some European countries have successfully controlled the dissemination of the 027 clone whereas other countries reported the emergence of other virulent or unusual strains. The aims of this review are to summarize the current European CDI epidemiology and to describe the new virulent C. difficile strains circulating in Europe, as well as other potential emerging strains described elsewhere. Standardized typing methods and surveillance programmes are mandatory for a better understanding and monitoring of CDI in Europe.

Dental referrals for patients with diabetes: survey of barriers and enablers for medical and health professionals

BACKGROUND

Oral health care improves diabetes management; however, medical and other health practitioners do not commonly refer their patients with diabetes for oral health care. This study aimed to understand barriers to and enablers of dental referrals for patients with diabetes.

METHODS

Quantitative data were collected from a cross-sectional survey of health care providers attending a virtual Grand Rounds on the relationship between oral health and diabetes. Attendees were invited to complete and share a Forms survey. Barriers to and enablers of dental referrals were compared for 18 health professionals working in inpatient/ward settings to 23 working in community/primary care settings using the chi-square test.

RESULTS

Across both work settings, only 12% of respondents often or always discussed the importance of oral health and only 8% often or always referred their patients with diabetes for dental care. Time barriers, awareness and knowledge of how/where to send dental referrals were significant barriers, while online referral pathways, more education and availability of brochures for the patient to take home were identified as key enablers for dental referrals.

CONCLUSIONS

Online referral pathways, targeted oral health education and resources for medical and health professionals caring for patients with diabetes may increase the number of patients being referred for dental care as part of their diabetes managements. © 2023 Australian Dental Association.

Evaluation of the diagnostic accuracy of two point-of-care tests for COVID-19 when used in symptomatic patients in community settings in the UK primary care COVID diagnostic accuracy platform trial (RAPTOR-C19)

BACKGROUND AND OBJECTIVE

Point-of-care lateral flow device antigen testing has been used extensively to identify individuals with active SARS-CoV-2 infection in the community. This study aimed to evaluate the diagnostic accuracy of two point-of-care tests (POCTs) for SARS-CoV-2 in routine community care.

METHODS

Adults and children with symptoms consistent with suspected current COVID-19 infection were prospectively recruited from 19 UK general practices and two COVID-19 testing centres between October 2020 and October 2021. Participants were tested by trained healthcare workers using at least one of two index POCTs (Roche-branded SD Biosensor Standard™ Q SARS-CoV-2 Rapid Antigen Test and/or BD Veritor™ System for Rapid Detection of SARS-CoV-2). The reference standard was laboratory triplex reverse transcription quantitative PCR (RT-PCR) using a combined nasal/oropharyngeal swab. Diagnostic accuracy parameters were estimated, with 95% confidence intervals (CIs), overall, in relation to RT-PCR cycle threshold and in pre-specified subgroups.

RESULTS

Of 663 participants included in the primary analysis, 39.2% (260/663, 95% CI 35.5% to 43.0%) had a positive RT-PCR result. The SD Biosensor POCT had sensitivity 84.0% (178/212, 78.3% to 88.6%) and specificity 98.5% (328/333, 96.5% to 99.5%), and the BD Veritor POCT had sensitivity 76.5% (127/166, 69.3% to 82.7%) and specificity 98.8% (249/252, 96.6% to 99.8%) compared with RT-PCR. Sensitivity of both devices dropped substantially at cycle thresholds ≥30 and in participants more than 7 days after onset of symptoms.

CONCLUSIONS

Both POCTs assessed exceed the Medicines and Healthcare products Regulatory Agency target product profile's minimum acceptable specificity of 95%. Confidence intervals for both tests include the minimum acceptable sensitivity of 80%. In symptomatic patients, negative results on these two POCTs do not preclude the possibility of infection. Tests should not be expected to reliably detect disease more than a week after symptom onset, when viral load may be reduced.

REGISTRATION

ISRCTN142269.

Ethnic differences in complement system biomarkers and their association with metabolic health in men of Black African and White European ethnicity

Inflammation plays a fundamental role in the development of several metabolic diseases, including obesity and type 2 diabetes (T2D); the complement system has been implicated in their development. People of Black African (BA) ethnicity are disproportionately affected by T2D and other metabolic diseases but the impact of ethnicity on the complement system has not been explored. We investigated ethnic differences in complement biomarkers and activation status between men of BA and White European (WE) ethnicity and explored their association with parameters of metabolic health. We measured a panel of 15 complement components, regulators, and activation products in fasting plasma from 89 BA and 96 WE men. Ethnic differences were statistically validated. Association of complement biomarkers with metabolic health indices (BMI, waist circumference, insulin resistance, and HbA1c) were assessed in the groups. Plasma levels of the key complement components C3 and C4, the regulators clusterin and properdin and the activation marker iC3b were significantly higher in BA compared to WE men after age adjustment, while FD levels were significantly lower. C3 and C4 levels positively correlated with some or all markers of metabolic dysfunction in both ethnic groups while FD was inversely associated with HbA1c in both groups, and clusterin and properdin were inversely associated with some markers of metabolic dysfunction only in the WE group. Our findings of increased levels of complement components and activation products in BA compared to WE men suggest differences in complement regulation that may impact susceptibility to poor metabolic health.

Assessment of Dietary Intake in Three Cohorts of Advanced Age in Two Countries: Methodology Challenges

OBJECTIVES

Dietary intake information is key to understanding nutrition-related outcomes. Intake changes with age and some older people are at increased risk of malnutrition. Application, difficulties, and advantages of the 24-hour multiple pass recall (24hr-MPR) dietary assessment method in three cohorts of advanced age in the United Kingdom (UK) and New Zealand (NZ) is described.

PARTICIPANTS

The Newcastle 85+ study (UK) recruited a single year birth cohort of people aged 85 years during 2006-7. LiLACS NZ recruited a 10-year birth cohort of Māori (indigenous New Zealanders) aged 80-90 years and a single year birth cohort of non-Māori aged 85 years in 2010.

MEASUREMENTS

Two 24hr-MPR were conducted on non-consecutive days by trained assessors. Pictorial resources and language were adapted for the New Zealand and Māori contexts. Detailed methods are described.

RESULTS

In the Newcastle 85+ study, 805 (93%) participants consented to the 24-MPR, 95% of whom completed two 24hr-MPR; in LiLACS NZ, 218 (82%) consented and 203 (76%) Māori and 353 (90%) non-Māori completed two 24hr-MPR. Mean time to complete each 24hr-MPR was 22 minutes in the Newcastle 85+ study, and 45 minutes for Māori and 39 minutes for non-Māori in LiLACS NZ. Dietary assessment of participants residing in residential care and those requiring proxy respondents were successfully included in both studies. Most participants (83-94%) felt that data captured by the 24hr-MPR reflected their usual dietary intake.

CONCLUSIONS

Dietary assessment using 24hr-MPR was successful in capturing detailed dietary data including information on portion size and time of eating for over 1300 octogenarians in the UK and New Zealand (Māori and non- Māori). The 24hr-MPR is an acceptable method of dietary assessment in this age group.

Clostridioides difficile infection (CDI): A pan-European multi-center cost and resource utilization study, results from the Combatting Bacterial Resistance in Europe CDI (COMBACTE-CDI)

OBJECTIVES

Clostridioides difficile infection (CDI) is one of the leading nosocomial infections worldwide, resulting in a significantly increasing burden on the healthcare systems. However, Pan-European data about cost and resource utilization of CDI treatment do not exist.

METHODS

A retrospective analysis within the Combatting Bacterial Resistance in Europe CDI project was conducted based on resource costs for inpatient treatment and productivity costs. Country-specific cost values were converted to EURO referred to 1 January, 2019 values. Differences in price levels for healthcare services among the participating countries were adjusted by using an international approach of the Organisation for Economic Co-operation and Development. As the study focused on patients with recurrent CDI, the observed study population was categorized into (a) patients with CDI but without CDI recurrence (case group), (b) patients with CDI recurrence (recurrence group), and (c) patients without CDI (control group).

RESULTS

Overall, 430 hospitalized patients from 12 European countries were included into the analysis between July 2018 and November 2018. Distribution of mean hospital length of stay and mean overall costs per patient between the case group, recurrence group, and control group were as follows: 22 days (95% CI 17-27 days) vs. 55 days (95% CI 17-94 days) vs. 26 days (95% CI 22-31 days; p 0.008) and € 15 242 (95% CI 10 593-19 891) vs. € 52 024 (95% CI 715-103 334) vs. € 21 759 (95% CI 16 484-27 035; p 0.010), respectively. The CDI recurrence rate during the observational period was 18%. Change escalation in CDI medication (OR 3.735) and treatment in an intensive care unit (OR 5.454) were found to be the most important variables associated with increased overall costs of patients with CDI.

CONCLUSIONS

Treatment of patients with recurrent CDI results in a significant burden. Prevention of CDI recurrences should be in focus of daily patient care to identify the most cost-effective treatment strategy.

Cohort profile: the ESC EURObservational Research Programme Non-ST-segment elevation myocardial infraction (NSTEMI) Registry

AIMS

The European Society of Cardiology (ESC) EURObservational Research Programme (EORP) Non-ST-segment elevation myocardial infarction (NSTEMI) Registry aims to identify international patterns in NSTEMI management in clinical practice and outcomes against the 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without ST-segment-elevation.

METHODS AND RESULTS

Consecutively hospitalised adult NSTEMI patients (n = 3620) were enrolled between 11 March 2019 and 6 March 2021, and individual patient data prospectively collected at 287 centres in 59 participating countries during a two-week enrolment period per centre. The registry collected data relating to baseline characteristics, major outcomes (in-hospital death, acute heart failure, cardiogenic shock, bleeding, stroke/transient ischaemic attack, and 30-day mortality) and guideline-recommended NSTEMI care interventions: electrocardiogram pre- or in-hospital, pre-hospitalization receipt of aspirin, echocardiography, coronary angiography, referral to cardiac rehabilitation, smoking cessation advice, dietary advice, and prescription on discharge of aspirin, P2Y12 inhibition, angiotensin converting enzyme inhibitor (ACEi)/angiotensin receptor blocker (ARB), beta-blocker, and statin.

CONCLUSION

The EORP NSTEMI Registry is an international, prospective registry of care and outcomes of patients treated for NSTEMI, which will provide unique insights into the contemporary management of hospitalised NSTEMI patients, compliance with ESC 2015 NSTEMI Guidelines, and identify potential barriers to optimal management of this common clinical presentation associated with significant morbidity and mortality.

Perceived feasibility, facilitators and barriers to incorporating point-of-care testing for SARS-CoV-2 into emergency medical services by ambulance service staff: a survey-based approach

OBJECTIVES

This body of work aimed to elicit ambulance service staff's perceptions on the barriers and facilitators to adoption, and clinical utility of incorporating rapid SARS-CoV-2 testing during ambulance assessments.

DESIGN

A mixed-methods survey-based project using a framework analysis method to organise qualitative data.

SETTING

Emergency and non-emergency care ambulatory services in the UK were approached to take part.

PARTICIPANTS

Current, practising members of the UK ambulance service (paramedics, technicians, assistants and other staff) were included in this body of work.

RESULTS

Survey 1: 226 responses were collected between 3 December 2020 and 11 January 2021, 179 (79.2%) of which were completed in full. While the majority of respondents indicated that an ambulance-based testing strategy was feasible in concept (143/190, 75.3%), major barriers to adoption were noted. Many open-ended responses cited concerns regarding misuse of the service by the general public and other healthcare services, timing and conveyance issues, and increased workloads, alongside training and safety concerns. Survey 2: 26 responses were received between 8 February 2021 and 22 February 2021 to this follow-up survey. Survey 2 revealed conveyance decision-making, and risk stratification to be the most frequently prioritised use cases among ambulance service staff. Optimal test characteristics for clinical adoption according to respondents were; accuracy (above 90% sensitivity and specificity), rapidity (<30 min time to results) and ease of sample acquisition.

CONCLUSIONS

The majority of commercially available lateral flow devices are unlikely to be supported by paramedics as their duty of care requires both rapid and accurate results that can inform clinical decision making in an emergency situation. Further investigation is needed to define acceptable test characteristics and criteria required for ambulance service staff to be confident and supportive of deployment of a SARS-CoV-2 test in an emergency care setting.

Advancing our understanding of skeletal muscle across the lifecourse: Protocol for the MASS_Lifecourse study and characteristics of the first 80 participants

INTRODUCTION

Sarcopenia, the age-related loss of skeletal muscle strength and mass, carries a significant burden for affected individuals. There has been little investigation of sarcopenia using experimental medicine techniques to study human muscle tissue in detail. The aim of the Muscle Ageing Sarcopenia Studies Lifecourse (MASS_Lifecourse) study is to recruit up to 160 participants, equally divided between females and males between ages 45 and 85 years for detailed phenotyping of skeletal muscle health. Here we describe the protocol for the study and the characteristics of the first 80 participants.

METHODS

We are recruiting participants from three sources in the north-east of England. Study fieldwork comprises a home visit (or videocall) for consent and assessment of health, cognition, lifestyle, and wellbeing. This is followed by a visit to a clinical research facility for assessment of sarcopenia status and collection of samples including a vastus lateralis muscle biopsy. We produced descriptive statistics for the first 80 participants, including expressing their grip strength relative to normative data in the form of Z-scores.

RESULTS

The first 80 participants (53.8 % female) covered the target ages, ranging from 48 to 84 years. They were regularly physically active, reported good physical function and had a prevalence of sarcopenia (including probable sarcopenia) of 11.3 % based on the revised European consensus. Their grip strength was similar to that in the general population, with a mean Z-score of 0.09 standard deviations (95 % CI: -1.64, 1.83) above that expected.

CONCLUSIONS

The MASS_Lifecourse study combines comprehensive health and lifestyle data with a range of biological samples including skeletal muscle. The findings from planned analyses should contribute to improvements in the diagnosis, treatment, and prevention of sarcopenia.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

AB1209 MECHANISTIC FACTORS CONTRIBUTING TO PAIN AND FATIGUE IN FIBROMYALGIA AND ME/CFS: AUTONOMIC AND INFLAMMATORY INSIGHTS FROM AN EXPERIMENTAL MEDICINE STUDY

Background

Fibromyalgia and ME/CFS are multifaceted conditions with overlapping symptoms(1); the pathoaetiological mechanisms are complex and debated(2), however there is a strong association with features of hereditary disorders of connective tissue (hypermobility) and autonomic and inflammatory abnormalities (1,2).

Objectives

To determine potential autonomic and inflammatory mechanisms of pain and fatigue in fibromyalgia and ME/CFS

Methods

After excluding participants with WCC higher than 10 (suggesting acute infection) baseline markers of inflammation (CRP and ESR) were available for 60 patients with confirmed diagnoses of Fibromyalgia and/ or ME/CFS and 23 matched controls. Participants then underwent full research diagnostic evaluation including a hypermobility assessment(1) and autonomic challenge (60 degree head up tilt, ISRCTN78820481). Subjective pain and fatigue were assessed before and after challenge (VAS). Linear regression models were used to explore predictors, with adjustment for confounders as appropriate. Mediation analyses (looking for mechanistic effects) were conducted according to the method of Hayes (3) and mediation considered significant if bootstrapped confidence intervals of the estimated indirect effect did not cross zero. In these mediation analyses predictor variable was group membership (patient or control), outcome variable was change in 1)pain and 2)fatigue induced by challenge and mediatiors 1)no of connective tissue features in hypermobility diagnostic criteria endorsed by participant; 2)baseline inflammatory markers.

Results

ESR and CRP were significantly higher in patients rather than controls, even after correcting for BMI, age and sex (B=5.15, t=2.05, p=0.044; B=1.77, t=2.15, p=0.044 respectively). Adjusted ESR and CRP correlated with both subjective fatigue (B=0.44, t=2.09, p=0.04; B=1.63, t=2.60, p=0.011) and pain severity (B=0.13, t=2.51, p=0.014; B=0.45, t=3.01, p=0.004) at baseline. Autonomic challenge amplified pain (B=14.20, t=2.87, p=0.005) and fatigue (B=31.48, t=5.95, p=<0.001) in patients to a significantly greater degree than controls, controlling for baseline levels. Baseline ESR and CRP also predicted challenge-induced increase in fatigue (B=0.78, t=370, p=<0.001; B=1.91, t=3.36, p=<0.001) and ESR challenge-induced increases in pain (B=0.46, t=2.35, p=0.021).

Mediation analysis demonstrated that number of connective tissue features expressed in hypermobility criteria mediated the degree to which subjective pain was increased by the autonomic challenge (Bootstraped 95% CI of indirect effect do not cross zero, 0.1572 – 6.8171). ESR mediated the degree to which subjective fatigue was increased by the autonomic challenge (Bootstraped 95% CI of indirect effect do not cross zero,0.7541 – 7.3888).

Conclusion

To our knowledge this is the first study to directly explore autonomic and inflammatory mechanisms of pain and fatigue in a combined population of Fibromyalgia and ME/CFS. This study this adds to the evidence-base of baseline inflammatory abnormalities in fibromyalgia and ME/CFS. It highlights their potential role in predicting symptom severity and their potential mechanistic role in autonomic induced pain and fatigue, suggesting future treatment strategies.

References

[1]Eccles JA, Thompson B, Themelis K, Amato ML, Stocks R, Pound A, et al. Beyond bones: The relevance of variants of connective tissue (hypermobility) to fibromyalgia, ME/CFS and controversies surrounding diagnostic classification: an observational study. Clin Med (Lond). 2021;21(1):53-8.

[2]Eccles JA, Davies KA. The challenges of chronic pain and fatigue. Clin Med (Lond). 2021;21(1):19-27.

[3]Hayes AF. Partial, conditional, and moderated moderated mediation: Quantification, inference, and interpretation. Commun Monogr. 2018;85(1):4-40.

Disclosure of Interests

Jessica Eccles: None declared, Charlotte Thompson: None declared, Beth Thompson: None declared, Marisa Amato: None declared, Kristy Themelis: None declared, Hugo Critchley: None declared, Neil Harrison Grant/research support from: speakers bureau, Kevin Davies: None declared

Clostridioides difficile positivity rate and PCR ribotype distribution on retail potatoes in 12 European countries, January to June 2018

Background

While human-to-human transmission of Clostridioides difficile occurs often, other infection sources, including food, animals and environment, are under investigation.

Aim

We present a large study on C. difficile in a food item in Europe, encompassing 12 European countries (Austria, France, Greece, Ireland, Italy, the Netherlands, Poland, Slovakia, Spain, Sweden, Romania and the United Kingdom).

Methods

Potato was selected because of availability, ease of sampling and high C. difficile positivity rates. Identical protocols for sampling and isolation were used, enabling a direct comparison of the C. difficile positivity rate.

Results

From C. difficile-positive potato samples (33/147; 22.4%), we obtained 504 isolates, grouped into 38 PCR ribotypes. Positivity rates per country varied (0–100%) and were at least 10% in 9/12 countries. No geographical clustering of samples with high positivity rates or in PCR ribotype distribution was observed. The most frequently detected PCR ribotypes (014/020, 078/126, 010 and 023) are also commonly reported in Europe among human clinically relevant isolates, in animal isolates and in the environment. Whole genome sequencing revealed several genetically related strain pairs (Spain/RT126, France/RT010, Austria and Sweden/RT276) and a cluster of very similar strains in RT078/126.

Conclusion

Our results suggest, the high potato contamination rates could have public health relevance. They indicate potatoes can serve as a vector for introducing C. difficile spores in the household environment, where the bacterium can then multiply in sensitive hosts with disrupted or unmature microbiota. Potato contamination with PCR ribotypes shared between humans, animals and soil is supportive of this view.

The assessment of sarcopenia and the frailty phenotype in the outpatient care of older people: implementation and typical values obtained from the Newcastle SarcScreen project

Aim

Is it possible to implement the Newcastle SarcScreen, an assessment of sarcopenia and physical frailty, as part of the outpatient care of older people?

Findings

Grip strength measurement was possible in 98.2% and gait speed in 82.1%, with the latter typically not measured due to mobility impairment. We found a high prevalence of probable sarcopenia and the frailty phenotype across all age groups studied.

Message

We successfully implemented the Newcastle SarcScreen. The proforma is available to download as part of this article.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-022-00641-5.

Purpose

Sarcopenia and the frailty phenotype both indicate older adults at risk of adverse health outcomes and yet are not widely assessed in practice. We developed the Newcastle SarcScreen to enable assessment of these two ageing syndromes during clinical care. In the setting of our Older People’s Medicine Day Unit, our aims were to describe the implementation of the SarcScreen and to examine the typical values obtained.

Methods

The SarcScreen comprised height, weight, questions (three on the Fried frailty phenotype and five on the SARC-F questionnaire), grip strength and gait speed. We analysed data from 552 patients completing the SarcScreen. We expressed grip strength as Z-scores (number of standard deviations above the mean expected for a patient’s age and sex).

Results

It was possible to implement the SarcScreen. In 552 patients (65.9% females) with mean age 80.1 (7.7) years, grip strength was feasible in 98.2% and gait speed in 82.1%. Gait speed was typically not assessed due to mobility impairment. Most patients had weak grip strength (present in 83.8%), slow gait speed (88.8%) and the frailty phenotype (66.2%). We found a high prevalence of probable sarcopenia and the frailty phenotype across all age groups studied. This was reflected by low grip strength Z-scores, especially at younger ages: those aged 60–69 had grip strength 2.7 standard deviations (95% CI 2.5–2.9) below that expected.

Conclusion

It is possible to implement an assessment of sarcopenia and the frailty phenotype as part of the routine outpatient care of older people.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-022-00641-5.

Reverse-Transcription Loop-Mediated Isothermal Amplification Has High Accuracy for Detecting Severe Acute Respiratory Syndrome Coronavirus 2 in Saliva and Nasopharyngeal/Oropharyngeal Swabs from Asymptomatic and Symptomatic Individuals

Previous studies have described reverse-transcription loop-mediated isothermal amplification (RT-LAMP) for the rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal/oropharyngeal swab and saliva samples. This multisite clinical evaluation describes the validation of an improved sample preparation method for extraction-free RT-LAMP and reports clinical performance of four RT-LAMP assay formats for SARS-CoV-2 detection. Direct RT-LAMP was performed on 559 swabs and 86,760 saliva samples and RNA RT-LAMP on extracted RNA from 12,619 swabs and 12,521 saliva samples from asymptomatic and symptomatic individuals across health care and community settings. For direct RT-LAMP, overall diagnostic sensitivity (DSe) was 70.35% (95% CI, 63.48%-76.60%) on swabs and 84.62% (95% CI, 79.50%-88.88%) on saliva, with diagnostic specificity of 100% (95% CI, 98.98%-100.00%) on swabs and 100% (95% CI, 99.72%-100.00%) on saliva, compared with quantitative RT-PCR (RT-qPCR); analyzing samples with RT-qPCR ORF1ab CT values of ≤25 and ≤33, DSe values were 100% (95% CI, 96.34%-100%) and 77.78% (95% CI, 70.99%-83.62%) for swabs, and 99.01% (95% CI, 94.61%-99.97%) and 87.61% (95% CI, 82.69%-91.54%) for saliva, respectively. For RNA RT-LAMP, overall DSe and diagnostic specificity were 96.06% (95% CI, 92.88%-98.12%) and 99.99% (95% CI, 99.95%-100%) for swabs, and 80.65% (95% CI, 73.54%-86.54%) and 99.99% (95% CI, 99.95%-100%) for saliva, respectively. These findings demonstrate that RT-LAMP is applicable to a variety of use cases, including frequent, interval-based direct RT-LAMP of saliva from asymptomatic individuals who may otherwise be missed using symptomatic testing alone.

Point of care testing using rapid automated antigen testing for SARS-COV-2 in care homes – an exploratory safety, usability and diagnostic agreement evaluation

Introduction

Successful adoption of POCTs (Point-of-Care tests) for COVID-19 in care homes requires the identification of ideal use cases and a full understanding of the contextual and usability factors that affect test results and minimise biosafety risks. This paper presents a scoping-usability and test performance study of a microfluidic immunofluorescence assay for COVID-19 in care homes.

Methods

A mixed-methods evaluation was conducted in four UK care homes to scope usability and to assess the agreement with qRT-PCR. A dry run with luminescent dye was conducted to explore biosafety issues.

Results

The agreement analysis was conducted on 227 asymptomatic participants (159 staff and 68 residents) and 14 symptomatic participants (5 staff and 9 residents). Asymptomatic specimens showed 50% (95% CI:1.3%−98.7%) positive agreement and 96% (95% CI: 92.5%−98.1%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.911 (95% CI: 0.857−0.965). Symptomatic specimens showed 83.3% (95% CI: 35.9%−99.6%) positive agreement and 100% (95% CI: 63.1%−100%) negative agreement with overall prevalence and bias-adjusted Kappa (PABAK) of 0.857 (95% CI: 0.549−1). The dry run highlighted four main sources of contamination that led to the modification of the standard operating procedures. Simulation post-modification showed no further evidence of contamination.

Conclusion

Careful consideration of biosafety issues and contextual factors associated with care home are mandatory for safe use the POCT. Whilst POCT may have some utility for ruling out COVID-19, further diagnostic accuracy evaluations are needed to promote effective adoption.

COVID-19 rapid diagnostics: practice review

Point-of-care tests for SARS-CoV-2 could enable rapid rule-in and/or rule-out of COVID-19, allowing rapid and accurate patient cohorting and potentially reducing the risk of nosocomial transmission. As COVID-19 begins to circulate with other more common respiratory viruses, there is a need for rapid diagnostics to help clinicians test for multiple potential causative organisms simultaneously.However, the different technologies available have strengths and weaknesses that must be understood to ensure that they are used to the benefit of the patient and healthcare system. Device performance is related to the deployed context, and the diagnostic characteristics may be affected by user experience.This practice review is written by members of the UK's COVID-19 National Diagnostic Research and Evaluation programme. We discuss relative merits and test characteristics of various commercially available technologies. We do not advocate for any given test, and our coverage of commercially supplied tests is not intended to be exhaustive.

Development and clinical validation of an automated cell cytotoxicity neutralization assay for detecting Clostridioides difficile toxins in clinically relevant stools samples

OBJECTIVES

To improve the diagnostic accuracy of Clostridioides difficile infection, current U.S. and E.U. guidelines recommend multistep testing that detects the presence of C. difficile and toxin in clinically relevant stool samples to confirm active disease. An accepted gold standard to detect C. difficile toxins is the cell cytotoxicity neutralization assay (CCNA). Although highly sensitive, the traditional CCNA has limitations. One such limitation is the subjective interpretation of an analyst to recognize cytopathic effects in cultured cells exposed to a fecal sample containing toxin. To overcome this limitation, an automated CCNA was developed that replaces most human pipetting steps with robotics and incorporates CellTiterGlo® for a semi-quantitative, non-subjective measure of cell viability instead of microscopy.

METHODS

To determine sample positivity and control for non-specific cytopathic effects, two thresholds were defined and validated by evaluating the sample with/without antitoxin antisera (sample-antitoxin/sample + antitoxin): 1) a >70% cell viability threshold was validated with samples containing anti-toxin, and 2) a >1.2-fold difference cut-off where sample results above the cut-off are considered positive.

RESULTS

Assay validation demonstrated excellent accuracy, precision, and sample linearity with an LOD of 126.9 pg/mL toxin-B in stool. The positivity cut-offs were clinically validated by comparing 322 diarrheal stool sample results with those run in a predicate, microscopic readout-based CCNA. The automated CCNA demonstrated 96% sensitivity and 100% specificity compared with the predicate CCNA.

CONCLUSIONS

Overall, the automated CCNA provides a specific, sensitive, and reproducible tool to support determination of CDI epidemiology or the efficacy of interventions such as vaccines.

Is point-of-care testing feasible and safe in care homes in England? An exploratory usability and accuracy evaluation of a point-of-care polymerase chain reaction test for SARS-CoV-2

Introduction

Reliable rapid testing for COVID-19 is needed in care homes to reduce the risk of outbreaks and enable timely care. This study aimed to examine the usability and test performance of a point of care polymerase chain reaction (PCR) test for detection of SARS-CoV-2 (POCKIT^TM Central) in care homes.

Methods

POCKIT^TM Central was evaluated in a purposeful sample of four UK care homes. Test agreement with laboratory real-time PCR and usability and used errors were assessed.

Results

No significant usability-related hazards emerged, and the sources of error identified were found to be amendable with minor changes in training or test workflow. POCKIT^TM Central has acceptable sensitivity and specificity based on RT-PCR as the reference standard, especially for symptomatic cases.

Asymptomatic specimens showed 83.3% (95% confidence interval (CI): 35.9–99.6%) positive agreement and 98.7% negative agreement (95% CI: 96.2–99.7%), with overall prevalence and bias-adjusted kappa (PABAK) of 0.965 (95% CI: 0.932– 0.999). Symptomatic specimens showed 100% (95% CI: 2.5–100%) positive agreement and 100% negative agreement (95% CI: 85.8–100%), with overall PABAK of 1.

Recommendations are provided to mitigate the frequency of occurrence of the residual use errors observed. Integration pathways were discussed to identify opportunities and limitations of adopting POCKIT™ Central for screening and diagnostic testing purposes.

Conclusions

Point-of-care PCR testing in care homes can be considered with appropriate preparatory steps and safeguards. Further diagnostic accuracy evaluations and in-service evaluation studies should be conducted, if the test is to be implemented more widely, to build greater certainty on this initial exploratory analysis.

Haem is crucial for medium-dependent metronidazole resistance in clinical isolates of Clostridioides difficile

Background

Until recently, metronidazole was the first-line treatment for Clostridioides difficile infection and it is still commonly used. Though resistance has been reported due to the plasmid pCD-METRO, this does not explain all cases.

Objectives

To identify factors that contribute to plasmid-independent metronidazole resistance of C. difficile.

Methods

Here, we investigate resistance to metronidazole in a collection of clinical isolates of C. difficile using a combination of antimicrobial susceptibility testing on different solid agar media and WGS of selected isolates.

Results

We find that nearly all isolates demonstrate a haem-dependent increase in the MIC of metronidazole, which in some cases leads to isolates qualifying as resistant (MIC >2 mg/L). Moreover, we find an SNP in the haem-responsive gene hsmA, which defines a metronidazole-resistant lineage of PCR ribotype 010/MLST ST15 isolates that also includes pCD-METRO-containing strains.

Conclusions

Our data demonstrate that haem is crucial for medium-dependent metronidazole resistance in C. difficile.

Ancient DNA, lipid biomarkers and palaeoecological evidence reveals construction and life on early medieval lake settlements

Direct evidence of ancient human occupation is typically established through archaeological excavation. Excavations are costly and destructive, and practically impossible in some lake and wetland environments. We present here an alternative approach, providing direct evidence from lake sediments using DNA metabarcoding, steroid lipid biomarkers (bile acids) and from traditional environmental analyses. Applied to an early Medieval Celtic settlement in Ireland (a crannog) this approach provides a site chronology and direct evidence of human occupation, crops, animal farming and on-site slaughtering. This is the first independently-dated, continuous molecular archive of human activity from an archeological site, demonstrating a link between animal husbandry, food resources, island use. These sites are under threat but are impossible to preserve in-situ so this approach can be used, with or without excavation, to produce a robust and full site chronology and provide direct evidence of occupation, the use of plants and animals, and activities such as butchery.

The effect of intestinal microbiota dysbiosis on growth and detection of carbapenemase-producing Enterobacterales within an in vitro gut model

BACKGROUND

Carbapenemase-producing Enterobacterales (CPE) can colonize the gut and are of major clinical concern. Identification of CPE colonization is problematic; there is no gold-standard detection method, and the effects of antibiotic exposure and microbiota dysbiosis on detection are unknown.

AIM

Based on a national survey we selected four CPE screening assays in common use. We used a clinically reflective in vitro model of human gut microbiota to investigate the performance of each test to detect three different CPE strains under different, clinically relevant antibiotic exposures.

METHODS

Twelve gut models were seeded with a pooled faecal slurry and exposed to CPE either before, after, concomitant with, or in the absence of piperacillin-tazobactam (358 mg/L, 3 × daily, seven days). Total Enterobacterales and CPE populations were enumerated daily. Regular screening for CPE was performed using Cepheid Xpert® Carba-R molecular test, and with Brilliance™ CRE, Colorex™ mSuperCARBA and CHROMID® CARBA SMART agars.

FINDINGS

Detection of CPE when the microbiota are intact is problematic. Antibiotic exposure disrupts microbiota populations and allows CPE proliferation, increasing detection. The performances of assays varied, particularly with respect to different CPE strains. The Cepheid assay performed better than the three agar methods for detecting a low level of CPE within an intact microbiota, although performance of all screening methods was comparable when CPE populations increased in a disrupted microbiota.

CONCLUSION

CPE strains differed in their dynamics of colonization in an in vitro gut model and in their subsequent response to antibiotic exposure. This affected detection by molecular and screening methods, which has implications for the sensitivity of CPE screening in healthcare settings.

The role of interoception in the mechanism of pain and fatigue in fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

Introduction

Pain, fatigue and anxiety are common features of fibromyalgia and ME/CFS and significantly impact quality of life. Aetiology is poorly defined but dysfunctional inflammatory, autonomic and interoceptive (sensing of internal bodily signals) processes are implicated.

Objectives

To investigate how altered interoception relates to baseline expression of pain, fatigue and anxiety symptoms in fibromyalgia and ME/CFS and in response to an inflammatory challenge.

Methods

Sixty-five patients with fibromyalgia and/or ME/CFS diagnosis and 26 matched controls underwent baseline assessment: pressure-pain thresholds and self-report questionnaires assessing pain, fatigue and anxiety severity. Participants received injections of typhoid (inflammatory challenge) or saline (placebo) in a randomised, double-blind, crossover design, before completing heartbeat tracking tasks. Three interoception dimensions were examined: subjective sensibility, objective accuracy and metacognitive awareness. Interoceptive trait prediction error was calculated as discrepancy between accuracy and sensibility.

Results

Patients with fibromyalgia and ME/CFS had significantly higher interoceptive sensibility and trait prediction error, despite no differences in interoceptive accuracy. Interoceptive sensibility and trait prediction error correlated with all self-report pain, fatigue and anxiety measures, and with lower pain thresholds. Anxiety mediated the positive-predictive relationships between pain (Visual Analogue Scale and Widespread Pain Index), fatigue impact and interoceptive sensibility. After inflammatory challenge, metacognitive awareness correlated with baseline self-reported symptom measures and lower pain thresholds.

Conclusions

This is the first study investigating interoceptive dimensions in patients with fibromyalgia and ME/CFS, which were found to be dysregulated and differentially influenced by inflammatory mechanisms. Interoceptive processes may represent a new potential target for diagnostic and therapeutic investigation in these poorly understood conditions.

Disclosure

No significant relationships.

24 Loneliness, Social Isolation and Frailty Among Older Adults in England: Results From the English Longitudinal Study of Ageing

Introduction

Ten percent of over 65 s and between a quarter and half of over 85 s are frail. Loneliness and social isolation are associated with increased falls, rates of hospitalisation and mortality. Lonely and socially isolated older adults may also be at risk of frailty. We examined the relationship between loneliness, social isolation and incident frailty among older adults in England longitudinally over 12 years.

Methods

The study sample are 9,171 older adults aged ≥50 years participating in a population representative longitudinal panel survey, the English Longitudinal Study of Ageing Waves 2–8. To define frailty across the biannual waves, we used the Frailty Index (FI), analysed continuously and into categories (FI ≤0.08 non-frail, 0.08–0.25 pre-frail and ≥ 0.25–1 frail). We used baseline (Wave 2): loneliness measure using the UCLA 3-item loneliness scale; social isolation measure using previously reported method (Banks et al. The Institute for Fiscal Studies. 2006.). Both were categorised into low/medium/high. To examine relationships, we used linear mixed methods modelling (for the continuous FI), and Cox proportional hazard model (for the categorical FI).

Results

Loneliness (β = 0.023; 95% CI = 0.022, 0.025) and social isolation (β = 0.007; 95% CI = 0.003, 0.010) were significantly associated with increased FI, after adjusting for cofounders (gender, age, marital status, smoking status and wealth). There was a 60% greater relative risk of belonging to the frail class with a medium loneliness score compared to low (HR = 1.570; 95% CI 1.492, 1.652) and a 160% greater relative risk with high loneliness score compared to low (HR = 2.621; 95% CI 2.488, 2.761). Although less pronounced, there was a 1% greater relative risk of developing frailty with a medium social isolation score compared to low (HR = 1.010, 95% CI 1.010, 1.197) and a 30% greater relative risk with high social isolation score compared to low (HR = 1.267; 95% CI 1.154, 1.390).

Conclusions

Our research indicates both loneliness and social isolation increase risk of developing frailty, expanding on previous evidence. This provides further support to the importance of understanding approaches to promote social inclusion of older adults.

Detection of SARS-CoV-2 within the healthcare environment: a multi-centre study conducted during the first wave of the COVID-19 outbreak in England

BACKGROUND

Understanding how severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is spread within the hospital setting is essential in order to protect staff, implement effective infection control measures, and prevent nosocomial transmission.

METHODS

The presence of SARS-CoV-2 in the air and on environmental surfaces around hospitalized patients, with and without respiratory symptoms, was investigated. Environmental sampling was undertaken within eight hospitals in England during the first wave of the coronavirus disease 2019 outbreak. Samples were analysed using reverse transcription polymerase chain reaction (PCR) and virus isolation assays.

FINDINGS

SARS-CoV-2 RNA was detected on 30 (8.9%) of 336 environmental surfaces. Cycle threshold values ranged from 28.8 to 39.1, equating to 2.2 x 105 to 59 genomic copies/swab. Concomitant bacterial counts were low, suggesting that the cleaning performed by nursing and domestic staff across all eight hospitals was effective. SARS-CoV-2 RNA was detected in four of 55 air samples taken <1 m from four different patients. In all cases, the concentration of viral RNA was low and ranged from <10 to 460 genomic copies/m3 air. Infectious virus was not recovered from any of the PCR-positive samples analysed.

CONCLUSIONS

Effective cleaning can reduce the risk of fomite (contact) transmission, but some surface types may facilitate the survival, persistence and/or dispersal of SARS-CoV-2. The presence of low or undetectable concentrations of viral RNA in the air supports current guidance on the use of specific personal protective equipment for aerosol-generating and non-aerosol-generating procedures.

Idiopathic systemic capillary leak syndrome (Clarkson's disease) presenting with recurrent hypovolemic shock

A 49-year old male with a past medical history of myocardial infarction and compartment syndromes requiring fasciotomies presented on five occasions with hypovolemic shock. We describe his admissions and presumptive diagnoses which required large volumes of intravenous fluids, admission to intensive care for vasopressors and renal replacement therapy. The presentations were always precipitated by a prodrome of fatigue and pre-syncopal episodes. On his last admission, a diagnosis of Idiopathic systemic capillary leak syndrome (ISCLS), also known as Clarkson's Disease, was reached. He is currently receiving high dose intravenous immunoglobulins on a monthly basis.

Snapshot PCR surveillance for SARS-CoV-2 in hospital staff in England

BACKGROUND

Significant nosocomial transmission of SARS-CoV-2 has been demonstrated. Understanding the prevalence of SARS-CoV-2 carriage amongst HCWs at work is necessary to inform the development of HCW screening programmes to control nosocomial spread.

METHODS

Cross-sectional 'snapshot' survey from April-May 2020; HCWs recruited from six UK hospitals. Participants self-completed a health questionnaire and underwent a combined viral nose and throat swab, tested by Polymerase Chain Reaction (PCR) for SARS-CoV-2 with viral culture on majority of positive samples.

FINDINGS

Point prevalence of SARS-CoV-2 carriage across the sites was 2.0% (23/1152 participants), median cycle threshold value 35.70 (IQR:32.42-37.57). 17 were previously symptomatic, two currently symptomatic (isolated anosmia and sore throat); the remainder declared no prior or current symptoms. Symptoms in the past month were associated with threefold increased odds of testing positive (aOR 3.46, 95%CI 1.38-8.67; p = 0.008). SARS-CoV-2 virus was isolated from only one (5%) of nineteen cultured samples. A large proportion (39%) of participants reported symptoms in the past month.

INTERPRETATION

The point-prevalence is similar to previous estimates for HCWs in April 2020, though a magnitude higher than in the general population. Based upon interpretation of symptom history and testing results including viral culture, the majority of those testing positive were unlikely to be infectious at time of sampling. Development of screening programmes must balance the potential to identify additional cases based upon likely prevalence, expanding the symptoms list to encourage HCW testing, with resource implications and risks of excluding those unlikely to be infectious with positive tests.

FUNDING

Public Health England.

An Analysis of Clostridium difficile Environmental Contamination During and After Treatment for C difficile Infection

Background

Lower Clostridium difficile spore counts in feces from C difficile infection (CDI) patients treated with fidaxomicin versus vancomycin have been observed. We aimed to determine whether environmental contamination is lower in patients treated with fidaxomicin compared with those treated with vancomycin/metronidazole.

Methods

The CDI cases were recruited at 4 UK hospitals (Leeds, Bradford, and London [2 centers]). Environmental samples (5 room sites) were taken pretreatment and at 2–3, 4–5, 6–8, and 9–12 days of treatment, end of treatment (EOT), and post-EOT. Fecal samples were collected at diagnosis and as often as produced thereafter. Swabs/feces were cultured for C difficile; percentage of C difficile-positive samples and C difficile bioburden were compared between different treatment arms at each time point.

Results

Pre-EOT (n = 244), there was a significant reduction in environmental contamination (≥1 site positive) around fidaxomicin versus vancomycin/metronidazole recipients at days 4–5 (30% vs 50% recipients, P = .04) and at days 9–12 (22% vs 49%, P = .005). This trend was consistently seen at all other timepoints, but it was not statistically significant. No differences were seen between treatment groups post-EOT (n = 76). Fidaxomicin-associated fecal positivity rates and colony counts were consistently lower than those for vancomycin/metronidazole from days 4 to 5 of treatment (including post-EOT); however, the only significant difference was in positivity rate at days 9–12 (15% vs 55%, P = .03).

Conclusions

There were significant reductions in C difficile recovery from both feces and the environment around fidaxomicin versus vancomycin/metronidazole recipients. Therefore, fidaxomicin treatment may lower the C difficile transmission risk by reducing excretion and environmental contamination.

Risk Factors for Primary Clostridium difficile Infection; Results From the Observational Study of Risk Factors for Clostridium difficile Infection in Hospitalized Patients With Infective Diarrhea (ORCHID)

Background: There are inconsistent data on the risk factors for Clostridium difficile infection (CDI) in the literature.

Aims: To use two C. difficile infection (CDI) case-control study groups to compare risk factors in hospitalized patients with diarrhea across different countries.

Methods: A multi-center group of CDI cases/controls were identified by standardized testing from seven countries from the prior EUropean, multi-center, prospective bi-annual point prevalence study of CLostridium difficile Infection in hospitalized patients with Diarrhea (EUCLID). A second group of CDI cases/controls was identified from a single center in Germany [parallel study site (PSS)]. Data were extracted from the medical notes to assess CDI risk factors. Univariate analyses and multivariate logistic regression models were used to identify and compare risk factors between the two groups.

Results: There were 253 and 158 cases and 921 and 584 controls in the PSS and EUCLID groups, respectively. Significant variables from univariate analyses in both groups were age ≥65, number of antibiotics (OR 1.2 for each additional antibiotic) and prior hospital admission (all p < 0.001). Congestive heart failure, diabetes, admission from assisted living or Emergency Department, proton pump inhibitors, and chronic renal disease were significant in PSS (all p < 0.05) but not EUCLID. Dementia and admitted with other bacterial diseases were significant in EUCLID (p < 0.05) but not PSS. Following multivariate analyses, age ≥ 65, number of antibiotics and prior hospital admission were consistently identified as CDI risk factors in each individual group and combined datasets.

Conclusion: Our results show that the same CDI risk factors were identified across datasets. These were age ≥ 65 years, antibiotic use and prior hospital admission. Importantly, the odds of developing CDI increases with each extra antibiotic prescribed.

AB0949 AUTONOMIC AND INFLAMMATORY MECHANISMS OF PAIN AND FATIGUE IN FIBROMYALGIA AND ME/CFS: AN INTERVENTIONAL STUDY

Background:

Fibromyalgia and ME/CFS are complex disorders with overlapping symptoms; the pathoaetiology and clinical distinction are debated, however inflammatory and autonomic abnormalities are observed.

Objectives:

To investigate the role of inflammatory and autonomic nervous system responses in mechanisms of pain and fatigue in fibromyalgia and ME/CFS

Methods:

63 patient participants with clinical diagnoses of fibromyalgia and/or ME/CFS were recruited into a multi-stage interventional study (ISRCTN78820481) alongside 24 healthy controls. All underwent research diagnostic criteria evaluation. The majority underwent autonomic challenge (60 degree head up tilt) and/or inflammatory challenge (placebo-controlled typhoid vaccination) with baseline characterisation of symptoms, inflammatory markers and pre-post measures of pain and fatigue.

Results:

Of the 63 patients, 32% of patients had received a clinical diagnosis of Fibromyalgia; 38% ME/CFS and 30% dual diagnoses. Following research evaluation 89% met ACR diagnostic criteria for fibromyalgia; 94% Canadian Criteria for ME/CFS; 97% Fukada Criteria for ME/CFS

There was a significantly higher ESR in patients compared to controls (p= 0.036). There was a trend towards higher CRP in patients compared to controls (p= 0.076).

ESR correlated with baseline pain score (r=0.309, p=0.011), fatigue severity (r=0.262, p=0.032), fatigue impact (r=0.382, p=0.014) change in fatigue score induced by tilt (r=0.319, p=0.011) and change in pain score induced by placebo-controlled inflammation (r=-0.279, p=0.043). Similarly CRP level correlated with baseline pain score (r=0.340, p=0.005), fatigue impact (r=0.439, p=0.004), change in fatigue (r=-0.277, p=0.045) and pain score (r=-0.394, p=0.014) induced by placebo-controlled inflammation and change in pressure pain theshold induced by tilt (r=0.286, p=0.027).

Baseline IL6 was higher in patients than controls (p = 0.002), correlating with baseline pain score (r = 0.345, p = 0.002) and change in pain score induced by tilt (r=0.281, p=0.21). Change in IL6 induced by inflammatory challenge correlated with inflammation induced fatigue score (r = 0.378, p = 0.01).

Conclusion:

Inflammatory and autonomic mechanisms contribute to pain and fatigue in this frequently overlooked patient group, highlighting possibilities for targeted treatments. Such data will be enriched going forward by neuroimaging and transcriptomic insights.

References:

n/a

Acknowledgments:

This work was supported by Versus Arthritis, Action for Me, Fibroduck Foundation and NIHR

Disclosure of Interests:

Jessica Eccles: None declared, Marisa Amato: None declared, Charlotte Thompson: None declared, Kristy Themelis: None declared, Hugo Critchley: None declared, Neil Harrison Grant/research support from: Yes, Speakers bureau: Yes, Kevin Davies: None declared

Factors affecting reported Clostridioides difficile infection rates; the more you look the more you find, but should you believe what you see?

Reported rates of C. difficile infection (CDI) have increased in many settings; however, these can be affected by factors including testing density (test-density) and diagnostic methods. We aimed to describe the impact of multiple factors on CDI rates. Hospitals (n = 182) across five countries (France, Germany, Italy, Spain, and UK) provided data on; size and type of institution, CDI testing methodology, number of tests/month and patient-bed-days (pbds)/month over one year. Incidence rates were compared between countries, different sized institutions, types of institutions and testing method. After univariate analyses, the highest CDI rates were observed in Italy (average 11.8/10,000pbds/hospital/month), acute/primary hospitals (12.3/10,000pbds/hospital/month), small hospitals (16.7/10,000pbds/hospital/month), and hospitals using methods that do not detect toxin (NO-TOXIN) (e.g. GDH/NAAT or standalone NAAT) (10.7/10,000pbds/hospital/month). After adjusting for test-density, highest incidence rates were still in Italy, acute/primary hospitals and those using NO-TOXIN. The relative rate in long-term healthcare facilities (LTHCFs) increased, but size of institution no longer influenced the CDI rate. Test-density appears to have the largest effect on reported CDI rates. NO-TOXIN testing still influences CDI rates, even after adjusting for test-density, which is consistent with tests that 'overcall' true CDI. Low test-density can mask the true burden of CDI, e.g. in LTHCFs, highlighting the importance of good quality surveillance.

Patient and Strain Characteristics Associated With Clostridium difficile Transmission and Adverse Outcomes

Background

No study has used whole-genome sequencing (WGS) to investigate risk factors for Clostridium difficile (CD) transmission between cases, or assessed the impact of recent acquisition on patient outcome.

Methods

This 20 month retrospective cohort study included consecutive cytotoxin-positive diarrheal samples, which underwent culture, ribotyping, and WGS (Illumina). Sequenced isolates were compared using single nucleotide variants (SNVs). Independent predictors of acquisition from another case, onward transmission, 120-day recurrence, and 30-day mortality were identified using logistic regression with backwards elimination.

Results

Of 660 CD cases, 640 (97%) were sequenced, of which 567 (89%) shared a ribotype with a prior case, but only 227 (35%) were ≤2 SNVs from a prior case, supporting recent acquisition. Plausible (<2 SNVs) recent ward-based acquisition from a symptomatic case was more frequent in certain ribotypes; 64% (67/105) for ribotype-027 cases, compared with 11% (6/57) for ribotype-078. Independent risk factors (adjusted P < .05) for CD acquisition included older age, longer inpatient duration, and ribotype; these factors, and male sex, increased onward transmission. Patients with a plausible donor had a greater risk of recurrence (adjusted P = .001) and trended towards greater 30-day mortality (adjusted P = .06). Ribotype had no additional mortality or recurrence impact after adjusting for acquisition (P > .1).

Conclusions

Greater transmission of certain lineages suggests CD may have different reservoirs and modes of transmission. Acquiring CD from a recent case is associated with poorer clinical outcomes. Clinical characteristics associated with increased healthcare-associated CD transmission could be used to target preventative interventions.

P4359Re-characterising the left ventricular outflow tract and annulus in bi- and tricuspid aortic valves by 3D echocardiography - Comparative insights and implications for aortic valve area calculations

Background

Aortic stenosis severity is defined by the calculated aortic valve area (AVA) using the Doppler-derived continuity equation (CE; AVACE = 0.785 x (LVOTd)2 x LVOT VTI/AV VTI (LVOTd = left ventricular outflow tract diameter; AV = aortic valve; VTI = velocity-time integral)). The LVOTd is the “Achilles heel” due to limitations of conventional 2D imaging and unstandardized measurement sites (0.5–1cm “apical” in the LVOT (LVOTdApi) vs “annulus” level (LVOTdAnn)) with no consensus even in recent guidelines. Geometrical differences in the LVOT and annulus of bicuspid (BAV) and tricuspid (TAV) aortic valves are further confounders. There remains a paucity of evidence to guide best practice. Erroneous LVOTd values will result in inaccurate AVACE estimations, triggering inappropriate intervention, or inaction.

Purpose

To define the optimal LVOTd by transthoracic echocardiography (TTE; LVOTdApi vs LVOTdAnn by 2D vs 3D) for AVACE calculation, and to identify factors accounting for any observed differences between BAVs and TAVs. AVA measured by 3D TTE planimetry (AVA3D) was the reference standard.

Methods

TTEs with 3D datasets of the AV complex in patients with BAVs and TAVs were included. 2D-LVOTdApi and 2D-LVOTdAnn were measured from 2D parasternal long-axis images. 3D-LVOTd values were calculated from the measured circumference, area, and average of minor/major dimensions at the “apical” (3D-LVOTdApi-Circ; 3D-LVOTdApi-Area; 3D-LVOTdApi-Ave) and “annulus” (3D-LVOTdAnn-Circ; 3D-LVOTdAnn-Area; 3D-LVOTdAnn-Ave) levels using multiplanar reconstruction. LVOTVTI and AVVTI were traced from standard spectral Doppler waveforms. The ratio of minor:major dimensions was used as an eccentricity index (EI) of the “apical” (EIApi) and “annulus” (EIAnn) sites.

Results

53 BAVs and 52 TAVs were included. Mean BAV-AVA3D and TAV-AVA3D were 3.48±0.93cm2 and 3.41±0.69cm2 respectively. In BAVs, estimated AVACE using 3D-LVOTdApi-Circ (3.43±1.05cm2; Intraclass correlation (ICC) 0.971) and 3D-LVOTdAnn-Circ (3.40±1.01cm2; ICC 0.968) correlated best with AVA3D. Conversely in TAVs, 3D-LVOTdApi-Area (3.29±0.69cm2; ICC 0.983) and 3D-LVOTdAnn-Area (3.24±0.70cm2; ICC 0.975) performed optimally. 3D-LVOTdApi-Circ and 3D-LVOTdAnn-Circ overestimated TAV-AVA3D due to the greater ellipticity of the “apical” and “annulus” sites in TAVs (TAV vs BAV: EIApi 0.78 vs 0.83, P=0.04; EIAnn 0.84 vs 0.90, P<0.005). 2D-LVOTd-derived AVACE were predictable underestimations of the AVA3D but the “annulus” level outperformed “apical” in both BAVs and TAVs (BAV-ICC 0.857 vs 0.771; TAV-ICC 0.917 vs 0.889).

Conclusions

The “apical” LVOT and “annulus” are more circular in BAVs where 3D circumference (3D-LVOTdApi-Circ or 3D-LVOTdAnn-Circ) yielded the best AVACE. The more elliptical geometry in TAVs resulted in 3D area (3D-LVOTdApi-Area or 3D-LVOTdAnn-Area) the preferred technique. Resolving the quandary of measurement site, 2D-LVOTdAnn is favored over 2D-LVOTdApi for both BAVs and TAVs.

Influence of Diagnostic Method on Outcomes in Phase 3 Clinical Trials of Bezlotoxumab for the Prevention of Recurrent Clostridioides difficile Infection: A Post Hoc Analysis of MODIFY I/II

Background

The optimum diagnostic test method for Clostridioides difficile infection (CDI) remains controversial due to variation in accuracy in identifying true CDI. This post hoc analysis examined the impact of CDI diagnostic testing methodology on efficacy outcomes in phase 3 MODIFY I/II trials.

Methods

In MODIFY I/II (NCT01241552/NCT01513239), participants received bezlotoxumab (10 mg/kg) or placebo during anti-CDI treatment for primary/recurrent CDI (rCDI). Using MODIFY I/II pooled data, initial clinical cure (ICC) and rCDI were assessed in participants diagnosed at baseline using direct detection methods (enzyme immunoassay [EIA]/cell cytotoxicity assay [CCA]) or indirect methods to determine toxin-producing ability (toxin gene polymerase chain reaction [tgPCR]/toxigenic culture).

Results

Of 1554 participants who received bezlotoxumab or placebo in MODIFY I/II, 781 (50.3%) and 773 (49.7%) were diagnosed by tgPCR/toxigenic culture and toxin EIA/CCA, respectively. Participants diagnosed by toxin EIA/CCA were more likely to be inpatients, older, and have severe CDI. In bezlotoxumab recipients, ICC rates were slightly higher in the toxin EIA/CCA subgroup (81.7%) vs tgPCR/toxigenic culture (78.4%). Bezlotoxumab significantly reduced the rCDI rate vs placebo in both subgroups; however, the magnitude of reduction was substantially larger in participants diagnosed by toxin EIA/CCA (relative difference, –46.6%) vs tgPCR/toxigenic culture (–29.1%). In bezlotoxumab recipients, the rCDI rate was lower in the toxin EIA/CCA subgroup (17.6%) vs tgPCR/toxigenic culture (23.6%; absolute difference, –6.0%; 95% confidence interval, –12.4 to 0.3; relative difference, –25.4%).

Conclusions

Diagnostic tests that detect fecal C. difficile toxins are of fundamental importance to accurately diagnosing CDI, including in clinical trial design, ensuring that therapeutic efficacy is not underestimated.

The perils of PCR-based diagnosis of Clostridioides difficile infections: Painful lessons from clinical trials

Diagnostic tests favoured to detect C. difficile infections (CDI) have undergone successive changes. The problem of over-diagnosis with polymerase chain reaction (PCR) testing is recognized in the clinical setting; here we discuss the parallel of the clinical trial setting. We summarize and discuss four examples of the impact of method used to diagnose CDI on clinical trial outcomes. Bezlotoxumab, a human monoclonal antibody neutralizing toxin B, was found to be protective against recurrent CDI (rCDI) in clinical trials. A post hoc analysis showed that the magnitude of the relative reduction in rCDI rates of bezlotoxumab over placebo in patients diagnosed with toxin-based testing was almost double that in patients diagnosed with PCR. SER-109, a microbiome therapeutic developed to prevent rCDI, showed promise in a phase 1b trial, but results were not replicated in a phase 2 trial in which diagnosis was in majority PCR-based. Surotomycin, an oral lipopeptide antibiotic, was found to be non-inferior to vancomycin in phase 2 study, but development was discontinued after unfavourable phase 3 results in which the majority of CDI were diagnosed by PCR. Finally, a C. difficile vaccine program for a toxoid vaccine developed by Sanofi/Pasteur was terminated after interim analysis of a phase 3 trial, in which CDI diagnosis was based solely on PCR. We highlighted the perils of using PCR alone in studies involving different aspects of C. difficile clinical research, including immunotherapies, microbiome-based therapies, treatments, and vaccines. The importance of designing C. difficile clinical trials with careful consideration to the diagnostic testing method cannot be overemphasized.