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BackgroundWhile human-to-human transmission of Clostridioides difficile occurs often, other infection sources, including food, animals and environment, are under investigation.AimWe 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).MethodsPotato 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.ResultsFrom 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.ConclusionOur 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.
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Clostridioides difficile , Infecções por Clostridium , Solanum tuberosum , Animais , Clostridioides , Clostridioides difficile/genética , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Europa (Continente)/epidemiologia , Humanos , Reação em Cadeia da Polimerase , Ribotipagem , Solanum tuberosum/genéticaRESUMO
BackgroundThere is a paucity of data on community-based Clostridioides difficile infection (CDI) and how these compare with inpatient CDI.AimTo compare data on the populations with CDI in hospitals vs the community across 12 European countries.MethodsFor this point-prevalence study (July-November 2018), testing sites sent residual diagnostic material on sampling days to a coordinating laboratory for CDI testing and PCR ribotyping (n = 3,163). Information on whether CDI testing was requested at the original site was used to identify undiagnosed CDI. We used medical records to identify differences between healthcare settings in patient demographics and risk factors for detection of C. difficile with or without free toxin.ResultsThe CDI positivity rate was 4.4% (country range: 0-16.2) in hospital samples, and 1.3% (country range: 0-2.2%) in community samples. The highest prevalence of toxinotype IIIb (027, 181 and 176) was seen in eastern European countries (56%; 43/77), the region with the lowest testing rate (58%; 164/281). Different predisposing risk factors were observed (use of broad-spectrum penicillins in the community (OR: 8.09 (1.9-35.6), p = 0.01); fluoroquinolones/cephalosporins in hospitals (OR: 2.2 (1.2-4.3), p = 0.01; OR: 2.0 (1.1-3.7), p = 0.02)). Half of community CDI cases were undetected because of absence of clinical suspicion, accounting for three times more undiagnosed adults in the community compared with hospitals (ca 111,000 vs 37,000 cases/year in Europe).ConclusionThese findings support recommendations for improving diagnosis in patients presenting with diarrhoea in the community, to guide good practice to limit the spread of CDI.
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Clostridioides difficile , Infecções por Clostridium , Infecção Hospitalar , Adulto , Clostridioides difficile/genética , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/epidemiologia , Infecção Hospitalar/epidemiologia , Estudos Transversais , Europa (Continente)/epidemiologia , Humanos , Pacientes Internados , Prevalência , RibotipagemRESUMO
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.
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Clostridioides difficile , Infecções por Clostridium , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Clostridioides , Clostridioides difficile/genética , Infecções por Clostridium/tratamento farmacológico , Heme , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , RibotipagemRESUMO
Neuroblastoma is an embryonal malignancy of the developing neural crest. Despite improvements in treatment, prognoses remain dire for patients with high-risk disease. Interest in this enigmatic cancer has led to a rapidly changing research landscape and we report on the recent advances in four themes that were discussed at the 3rd Neuroblastoma Research Symposium: (1) The epigenetic signature of neuroblastoma and the epigenetic control of tumour development, (2) novel approaches to targeting MYCN, (3) valuable in vivo modelling and (4) improving differentiation therapies based on a knowledge of normal sympathetic neuron development. Through lively discussion, the development of combined therapies with synergistic effects for which we have a good mechanistic understanding emerged as offering greatest promise. Drug synergies enhance efficacy but also specificity, the latter crucial for reducing long-term side effects in young children.
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Pesquisa Biomédica , Congressos como Assunto , Neuroblastoma/terapia , Epigênese Genética , Humanos , Neuroblastoma/diagnóstico , Neuroblastoma/genéticaRESUMO
Objectives: Clostridioides difficile epidemiology is evolving with country-associated emerging and resistant ribotypes (RT). Antimicrobial susceptibility testing of C. difficile isolated from clinical and animal samples collected across Europe in 2018 was performed to provide antimicrobial resistance data and according to C. difficile RTs and source. Methods: Samples were cultured for C. difficile and isolates PCR ribotyped. Metronidazole, vancomycin, fidaxomicin, moxifloxacin, clindamycin, imipenem, tigecycline, linezolid, rifampicin and meropenem minimum inhibitory concentrations (MICs) for 280 clinical and 126 animal isolates were determined by Wilkins-Chalgren agar dilution. Results: Fidaxomicin was the most active antimicrobial (all isolates geometric mean MICâ=â0.03 mg/L) with no evidence of reduced susceptibility. Metronidazole MICs were elevated among RT027 (1.87 mg/L) and RT181 clinical isolates (1.03 mg/L). RT027 and RT181 had elevated geometric mean moxifloxacin MICs (14.49 mg/L, 16.88 mg/L); clindamycin (7.5 mg/L, 9.1 mg/L) and rifampicin (0.6 mg/L, 21.5 mg/L). Five isolates (RT002, RT010 and RT016) were metronidazole resistant (MICâ=â8 mg/L) and 10 (RT027; RT198) had intermediate resistance (4 mg/L). Metronidazole MICs were not elevated in animal isolates. Increased geometric mean vancomycin MICs were observed among RT078, mostly isolated from animals, but there was no resistance (MICâ≥â4 mg/L). Clinical and animal isolates of multiple RTs showed resistance to moxifloxacin and clindamycin. No resistance to imipenem or meropenem was observed. Conclusion: Increased antimicrobial resistance was detected in eastern Europe and mostly associated with RT027 and related emerging RT181, while clinical isolates from northern and western Europe had the lowest general levels of resistance.
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OBJECTIVES: The prevalence of Clostridioides difficile infection (CDI) has been shown to vary markedly between European countries, both in hospitals and in the community. Determining the true prevalence has proven challenging. Without systematic testing in hospitals, the unchecked transmission of CDI can lead to large outbreaks in more susceptible cohorts. We investigate the success of CDI surveillance and control measures across Europe, by examining the dynamics of disease spread from the community into a hospital setting. We focus on national differences, such as variability in testing and sampling, disease prevalence in communities and hospitals, and antimicrobial usage. METHODS: We developed a stochastic, compartmental, dynamic mathematical model parameterized using sampling and testing rate data from COMBACTE-CDI, a multicountry study in which all diarrhoeal stool samples (N = 3163) from European laboratories were tested for CDI, and data for antimicrobial usage and incidence of hospital cases sourced from the European Centre for Disease Prevention and Control. RESULTS: The framework estimates the prevalence of CDI among hospital patients across European countries and explores how national differences impact the dynamics, transmission, and relative incidence of CDI within the hospital setting. The model illustrates the mechanisms influencing these national differences, namely, antimicrobial usage rates, national sampling and testing rates, and community prevalence of CDI. DISCUSSION: Differential costs for testing and practicalities of scaling up testing mean every country needs to consider balancing CDI testing costs against the costs of treatment and care of patients with CDI.
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Clostridioides difficile , Infecções por Clostridium , Infecção Hospitalar , Humanos , Europa (Continente)/epidemiologia , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Hospitais , Modelos Teóricos , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologiaRESUMO
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.
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Infecções por Clostridium , Hospitalização , Humanos , Estudos Retrospectivos , Custos de Cuidados de Saúde , Infecções por Clostridium/microbiologia , Europa (Continente) , RecidivaRESUMO
In many cancers, including neuroblastoma, microRNA (miRNA) expression profiling of peripheral blood (PB) and bone marrow (BM) may increase understanding of the metastatic process and lead to the identification of clinically informative biomarkers. The quality of miRNAs in PB and BM samples archived in PAXgene™ blood RNA tubes from large-scale clinical studies and the identity of reference miRNAs for standard reporting of data are to date unknown. In this study, we evaluated the reliability of expression profiling of 377 miRNAs using quantitative polymerase chain reaction (qPCR) in PB and BM samples (n=90) stored at -80 °C for up to 5 years in PAXgene™ blood RNA tubes. There was no correlation with storage time and variation of expression for any single miRNA (r < 0.50). The profile of miRNAs isolated as small RNAs or co-isolated with small/large RNAs was highly correlated (r=0.96). The mean expression of all miRNAs and the geNorm program identified miR-26a, miR-28-5p, and miR-24 as the most stable reference miRNAs. This study describes detailed methodologies for reliable miRNA isolation and profiling of PB and BM, including reference miRNAs for qPCR normalization, and demonstrates the suitability of clinical samples archived at -80 °C into PAXgene™ blood RNA tubes for miRNA expression studies.
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Medula Óssea/metabolismo , Perfilação da Expressão Gênica , MicroRNAs/sangue , MicroRNAs/genética , Criança , Hematopoese , Humanos , MicroRNAs/isolamento & purificação , Reação em Cadeia da PolimeraseRESUMO
Despite intensive treatment, 50% of children with high-risk neuroblastoma (HR-NB) succumb to their disease. Progression through current trials evaluating the efficacy of new treatments for children with HR disease usually depends on an inadequate response to induction chemotherapy, assessed using imaging modalities. In this study, we sought to identify circulating biomarkers that might be detected in a simple blood sample to predict patient response to induction chemotherapy. Since exosomes released by tumor cells can drive tumor growth and chemoresistance, we tested the hypothesis that exosomal microRNA (exo-miRNAs) in blood might predict response to induction chemotherapy. The exo-miRNAs expression profile in plasma samples collected from children treated in HR-NBL-1/SIOPEN before and after induction chemotherapy was compared to identify a three exo-miRs signature that could discriminate between poor and good responders. Exo-miRNAs expression also provided a chemoresistance index predicting the good or poor prognosis of HR-NB patients.
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The clinical utility of detecting minimal residual disease (MRD) in children with neuroblastoma (NB) by quantitative reverse transcriptase polymerase chain reaction (QRT-PCR) is not clear. This in part reflects the lack of uniform methodology for analysis and reporting. Reference laboratories across Europe have therefore established standard operating procedures (SOPs) for the detection of NB cells by QRT-PCR. Haemopoietic samples are collected into PAXgene blood RNA tubes, which stabilise mRNA for 48 h at room temperature and more than 6 months at -80 degrees C. Tyrosine hydroxylase (TH) was selected as the target for NB cell detection, expression is normalised to beta2-microglobulin and reported using the DeltaDeltaCt method. The sensitivity of QRT-PCR increased from 58% to 90% following the development of SOPs. A robust, transferable, objective method for the detection of NB cells by QRT-PCR has been defined to improve the power and consistency of studies on MRD in children with NB.
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Neoplasia Residual/diagnóstico , Neuroblastoma/diagnóstico , Linhagem Celular Tumoral , Criança , Pré-Escolar , Humanos , Lactente , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Controle de Qualidade , RNA Neoplásico/análise , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Manejo de Espécimes/normasRESUMO
The nitrogen-fixing symbiotic bacterium Rhizobium species NGR234 secretes, via a type III secretion system (TTSS), proteins called Nops (nodulation outer proteins). Abolition of TTSS-dependent protein secretion has either no effect or leads to a change in the number of nodules on selected plants. More dramatically, Nops impair nodule development on Crotalaria juncea roots, resulting in the formation of nonfixing pseudonodules. A double mutation of nopX and nopL, which code for two previously identified secreted proteins, leads to a phenotype on Pachyrhizus tuberosus differing from that of a mutant in which the TTSS is not functional. Use of antibodies and a modification of the purification protocol revealed that NGR234 secretes additional proteins in a TTSS-dependent manner. One of them was identified as NopA, a small 7-kDa protein. Single mutations in nopX and nopL were also generated to assess the involvement of each Nop in protein secretion and nodule formation. Mutation of nopX had little effect on NopL and NopA secretion but greatly affected the interaction of NGR234 with many plant hosts tested. NopL was not necessary for the secretion of any Nops but was required for efficient nodulation of some plant species. NopL may thus act as an effector protein whose recognition is dependent upon the hosts' genetic background.
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Proteínas de Bactérias/química , Rhizobium/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Dados de Sequência Molecular , Mutagênese , Mutação , Homologia de Sequência de Aminoácidos , SimbioseRESUMO
PURPOSE: To evaluate the hypothesis that detection of neuroblastoma mRNAs by reverse transcriptase quantitative polymerase chain reaction (RTqPCR) in peripheral blood (PB) and bone marrow aspirates (BM) from children with stage 4 neuroblastoma are clinically useful biomarkers of risk. METHODS: RTqPCR for paired-like homeobox 2b (PHOX2B), tyrosine hydroxylase (TH), and doublecortin (DCX) mRNA in PB and BM of children enrolled onto the High-Risk Neuroblastoma Trial-1 of the European Society of Pediatric Oncology Neuroblastoma Group (HR-NBL1/SIOPEN) was performed at diagnosis and after induction therapy. RESULTS: High levels of TH, PHOX2B, or DCX mRNA in PB or BM at diagnosis strongly predicted for worse event-free survival (EFS) and overall survival (OS) in a cohort of 290 children. After induction therapy, high levels of these mRNAs predicted worse EFS and OS in BM but not in PB. Combinations of mRNAs in BM did not add to the predictive power of any single mRNA. However, in the original (n = 182) and validation (n = 137) PB cohorts, high TH (log10TH > 0.8) or high PHOX2B (log10PHOX2B > 0.28) identify 19% of children as ultrahigh risk, with 5-year EFS and OS rates of 0%; OS rate was 25% (95% CI, 16% to 36%) and EFS rate was 38% (95% CI, 28% to 49%) in the remaining children. The magnitude of reduction in mRNA level between diagnosis and postinduction therapy in BM or PB was not of additional predictive value. CONCLUSION: High levels of TH and PHOX2B mRNA in PB at diagnosis objectively identify children with ultrahigh-risk disease who may benefit from novel treatment approaches. The level of TH, PHOX2B, and DCX mRNA in BM and/or PB at diagnosis might contribute to an algorithm to improve stratification of children for treatment.