Effects of clinical breakpoint changes in CLSI guidelines 2010/2011 and EUCAST guidelines 2011 on antibiotic susceptibility test reporting of Gram-negative bacilli

Objectives The aim of this study was to analyse the effects of clinical breakpoint changes in CLSI 2010 and 2011 guidelines and EUCAST 2011 guidelines on antibiotic susceptibility testing (AST) reports. Methods In total, 3713 non-duplicate clinical isolates of Enterobacteriaceae, Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Acinetobacter baumannii were analysed. Inhibition zone diameters were determined for β-lactams, carbapenems, fluoroquinolones, aminoglycosides and trimethoprim/sulfamethoxazole. CLSI 2009-11 and EUCAST 2011 clinical breakpoints were applied. Results Changes in resistance as defined per the guidelines affected individual species and drug classes differently. The cefepime resistance rate in Escherichia coli and Enterobacter cloacae increased from 2.1% and 1.3% to 8.2% and 6.9%, respectively, applying CLSI 2009-11 versus EUCAST 2011 guidelines. Ertapenem resistance rates in E. cloacae increased from 2.6% with CLSI 2009 to 7.2% for CLSI 2010 and 2011, and to 10.1% when applying EUCAST 2011. Cefepime and meropenem resistance rates in P. aeruginosa increased from 12.2% and 20.6% to 19.8% and 27.7%, respectively, comparing CLSI 2009-11 with EUCAST 2011. Tobramycin and gentamicin resistance rates in A. baumannii increased from 15.9% and 25.4% to 34.9% and 44.4% applying CLSI 2009-11 versus EUCAST 2011. Conclusions Higher resistance rates reported due to breakpoint changes in CLSI and EUCAST guidelines will result in increasing numbers of Gram-negative bacilli reported as multidrug resistant. AST reports classifying amoxicillin/clavulanic acid, cefepime or carbapenem resistance will lead clinicians to use alternative agents. Upon implementation of the EUCAST guidelines, laboratories should be aware of the implications of modified drug susceptibility testing reports on antibiotic prescription policie

Automated quantitative drug susceptibility testing of non-tuberculous mycobacteria using MGIT 960/EpiCenter TB eXiST

Objectives To assess the predictive value of in vitro drug susceptibility testing (DST) in slow-growing non-tuberculous mycobacteria (NTM), knowledge on quantitative levels of drug susceptibility should be available. The aim of this study was to investigate the suitability of the MGIT 960/TB eXiST system for quantitative DST of NTM. Methods We have assessed quantitative levels of drug susceptibility for clinical isolates of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium kansasii by comparing radiometric Bactec 460TB-based DST with non-radiometric DST using MGIT 960/TB eXiST. Results MGIT 960/TB eXiST gives results comparable to those of Bactec 460TB. Conclusions The MGIT 960/TB eXiST appears suitable for quantitative DST of NT

Evaluation of the AID ESBL line probe assay for rapid detection of extended-spectrum β-lactamase (ESBL) and KPC carbapenemase genes in Enterobacteriaceae

Objectives This study aimed at evaluating the AID ESBL line probe assay for the detection of extended-spectrum β-lactamase (ESBL) and KPC carbapenemase genes in Enterobacteriaceae. Methods The AID ESBL line probe assay was verified for accuracy of its probes using PCR products from clinical ESBL Enterobacteriaceae strains harbouring TEM, SHV and CTX-M ESBL genes and KPC genes and mutant fusion PCR products generated from Enterobacteriaceae strains containing wild-type (wt) TEM and wt SHV. Sensitivity and specificity was determined testing a set of 424 clinical Enterobacteriaceae strains (including 170 strains negative for TEM, SHV, CTX-M and KPC to evaluate the possibility of false positive signals). Results The line probe assay was shown to detect with 100% accuracy ESBL genes for which oligonucleotide probes are present in the assay. Testing a set of 424 clinical Enterobacteriaceae strains showed 100% sensitivity and specificity for the detection and differentiation of TEM, SHV and CTX-M ESBL genes present in that group. In addition, the line probe assay detected KPC genes accurately. Conclusions The AID ESBL line probe assay is an accurate and easy-to-use test for the detection of ESBL and KPC genes, which can readily be implemented in the diagnostic laborator

Predicting meiofauna abundance to define preservation and impact zones in a deep-sea mining context using random forest modelling

There is a strong economic interest in commercial deep‐sea mining of polymetallic nodules and therefore a need to define suitable preservation zones in the abyssal plain of the Clarion Clipperton Fracture Zone (CCZ). However, besides ship‐based multibeam data, only sparse continuous environmental information is available over large geographic scales. We test the potential of modelling meiofauna abundance and diversity on high taxonomic level on large geographic scale using a random forest approach. Ship‐based multibeam bathymetry and backscatter signal are the only sources for 11 predictor variables, as well as the modelled abundance of polymetallic nodules on the seafloor. Continuous meiofauna predictions have been combined with all available environmental variables and classified into classes representing abyssal habitats using k‐means clustering. Results show that ship‐based, multibeam‐derived predictors can be used to calculate predictive models for meiofauna distribution on a large geographic scale. Predicted distribution varies between the different meiofauna response variables. To evaluate predictions, random forest regressions were additionally computed with 1,000 replicates, integrating varying numbers of sampling positions and parallel samples per site. Higher numbers of parallel samples are especially useful to smoothen the influence of the remarkable variability of meiofauna distribution on a small scale. However, a high number of sampling positions is even more important, integrating a greater amount of natural variability of environmental conditions into the model. Synthesis and applications. Polymetallic nodule exploration contractors are required to define potential mining and preservation zones within their licence area. The biodiversity and the environment of preservation zones should be representative of the sites that will be impacted by mining. Our predicted distributions of meiofauna and the derived habitat maps are an essential first step to enable the identification of areas with similar ecological conditions. In this way, it is possible to define preservation zones not only based on expert opinion and environmental proxies but also integrating evidence from the distribution of benthic communities

1011-116 Myocardial Rb Extraction Fraction: Determination in Humans

Ouantitation of myocardial blood flow (MBF) with diffusion-limited radiotracers as 82Rb and positron emission tomography (PET) requires knowledge of flow dependence of myocardial 82Rb extraction fraction. To determine this dependence we evaluated 7 patients (mean age (61.0±9.7) years, 4 males, 3 females) who had undergone coronary angiography with exclusion of relevant coronary stenoses and normal left ventricular function. 82Rb-PET clearance was simultaneously assessed with global MBF by the argon (Ar) inert gas method. 82Rb clearance was dynamically measured by a CTI-Siemens ECAT 931-08-12 scanner after i.v. injection of 1–1.2 GBq 82Rb. Ar gas desaturation was obtained by simultaneous arterial and coronary sinus blood sampling. Measurements were performed at rest and during vasodilatation induced by i.v. dipyridamole (0.7mg/kg/4min). Mean 82Rb clearance and Ar flow values were (0.39±0,03)ml/g/min and (0.69±0.14)ml/g/min at rest, respectively, and (0.47±0.09)ml/g/min and (1.48±0.49)ml/g/min during hyperemia. A fit with a two compartment model yielded E=PS/(PS+MBF) with PS=(0.82±0.09)ml/g/min (PS: permeability surface area product). These data (figure) provide for the best of our knowledge the first measured 82Rb extraction fraction in humans and may form the basis for more accurate quantitation of myocardial blood flow with 82Rb-PET

Characterisation of Medipix3 Silicon Detectors in a Charged-Particle Beam

While designed primarily for X-ray imaging applications, the Medipix3 ASIC can also be used for charged-particle tracking. In this work, results from a beam test at the CERN SPS with irradiated and non-irradiated sensors are presented and shown to be in agreement with simulation, demonstrating the suitability of the Medipix3 ASIC as a tool for characterising pixel sensors.Comment: 16 pages, 13 figure

Quasifree eta photoproduction from nuclei and medium modifications of resonances

We investigate the sensitivity of the differential cross section, recoil nucleon polarization and the photon asymmetry to changes in the elementary amplitude, medium modifications of the resonance $(S_{11},D_{13})$ masses, as well as nuclear target effects. All calculations are performed within a relativistic plane wave impulse approximation formalism resulting in analytical expressions for all observables. The spin observables are shown to be unique tools to study subtle effects that are not accessible by only looking at the unpolarized differential cross section.Comment: 27 pages, 8 figures, Revtex, To be published in Phys. Rev.

Probing nuclear expansion dynamics with π−/π+\pi^-/\pi^+-spectra

We study the dynamics of charged pions in the nuclear medium via the ratio of differential $\pi^-$- and $\pi^+$-spectra in a coupled-channel BUU (CBUU) approach. The relative energy shift of the charged pions is found to correlate with the pion freeze-out time in nucleus-nucleus collisions as well as with the impact parameter of the heavy-ion reaction. Furthermore, the long-range Coulomb force provides a 'clock' for the expansion of the hot nuclear system. Detailed comparisons with experimental data for $Au + Au$ at 1 GeV/A and $Ni + Ni$ at 2.0 GeV/A are presented.Comment: 21 pages, latex, figures include

Photoproduction of mesons in nuclei at GeV energies

In a transport model that combines initial state interactions of the photon with final state interactions of the produced particles we present a calculation of inclusive photoproduction of mesons in nuclei in the energy range from 1 to 7 GeV. We give predictions for the photoproduction cross sections of pions, etas, kaons, antikaons, and $\pi^+\pi^-$ invariant mass spectra in ^{12}C and ^{208}Pb. The effects of nuclear shadowing and final state interaction of the produced particles are discussed in detail.Comment: Text added in summary in general reliability of the method, references updated. Phys. Rev. C (2000) in pres

Antenatal care service delivery and factors affecting effective tetanus vaccine coverage in low- and middle-income countries: results of the Maternal Immunisation and Antenatal Care Situational Analysis (MIACSA) project

Objectives:To map the integration of existing maternal tetanus immunization programmes within ante-natal care (ANC) services for pregnant women in low- and middle-income countries (LMICs) and to identify and understand the challenges, barriers and facilitators associated with high performance maternal vaccine service delivery.Design:A mixed methods, cross sectional study with four data collection phases including a desk review,online survey, telephone and face-to-face interviews and in country visits was undertaken between 2016 and 2018. Associations of different service delivery process components with protection at birth (PAB) andwithcountrygroupswereestablished.PABwasdefinedastheproportionofneonatesprotectedatbirthagainstneonataltetanus. Regression analysis and structural equation modelling was used to assess associations of different variables with maternal tetanus immunization coverage. Latent class analysis (LCA), was used to group country performance for maternal immunization, and to address the problem of multicollinearity.Setting:LMICs.Results: The majority of LMICs had a policy on recommended number of ANC visits, however most were yet toimplementtheWHOguidelinesrecommendingeightANCcontacts.Countriesthatrecommended>4ANC contacts were more likely to have high PAB > 90%. Passive disease surveillance was the most common form of dis-ease surveillance performed but the maternal and neonatal morbidity and mortality indicators recorded differed between countries. The presence of user fees for antenatal care and maternal immunization was significantly associated with lower PAB (<90%).Conclusions:Recommendations include implementing the current WHO ANC guideline to facilitate increased opportunities for vaccination during each pregnancy. Improved utilisation of ANC services by increasing the demand side by increasing the quality of services, reducing any associated costs and supporting user fee exemptions, or the supply side can also enhance utilisation of ANC services which are positioned as an ideal platform for delivery of maternal vaccine