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The rapid increase of OXA-244-producing Escherichia coli , predominantly driven by genetically clustered isolates of sequence type (ST)38, has been observed in at least nine European countries, including Germany. However, the reasons for the spread of OXA-244-producing E. coli remain unclear. Here, we aim to evaluate the possibility of prolonged carriage. We identified a total of six different patients with repeated detection of OXA-244-producing E. coli isolates, which were subjected to both short and long-read whole-genome sequencing (WGS). Besides allelic differences using core genome multilocus sequence typing (cgMLST) analyses, we obtained numbers of single-nucleotide polymorphisms (SNPs) to calculate individual base-pair substitution (BPS) rates. To assess possible re-exposure and risk factors for prolonged carriage, case interviews were conducted. The time between detections ranged from eleven months to more than three years. Initial isolates originated in three+ out of six cases from clinical samples, whereas remaining samples were from screening, mostly in the inpatient setting. As expected, cgMLST analyses showed low numbers of allelic differences between isolates of each case ranging from 1 to 4, whereas numbers of SNPs were between 2 and 99 (mean = 36), thus clearly highlighting the discrepancy between these different bacterial typing approaches. For five out of six cases, observed BPS rates suggest that patients can be colonized with OXA-244-producing E. coli , including ST38 cluster isolates, for extensively long times. Thus, we may have previously missed the epidemiological link between cases because exposure to OXA-244-producing E. coli could have occurred in a time frame, which has not been evaluated in previous investigations. Our results may help to guide future epidemiological investigations as well as to support the interpretation of genetic diversity of OXA-244-producing E. coli , particularly among ST38 cluster isolates. [ABSTRACT FROM AUTHOR]

The distribution of carbapenemase genes in Escherichia coli strains isolated between September 2009 and May 2013 in Germany was investigated. Out of 192 isolates with carbapenemase production OXA-48 was found in 44.8%, VIM-1 in 18.8%, NDM-1 in 11.5% and KPC-2 in 6.8%. Patients with VIM-1 producing E. coli ( n = 36) differed from patients with OXA-48 by an older age, less frequent mention of travel history and an increased proportion of clinical over screening specimens. These data might indicate that introduction from abroad is of minor importance for VIM-1 producing E. coli compared to other carbapenemases. Multilocus sequence typing revealed that E. coli with VIM-1 were mostly multiclonal, emphasizing the role of horizontal gene transfer in its spread. Susceptibility testing of VIM-1 producing E. coli demonstrated aztreonam susceptibility in 55.6%. Among non-β-lactams susceptibility rates of >90% were observed for amikacin, tigecycline, colistin, fosfomycin and nitrofurantoin. [ABSTRACT FROM AUTHOR]

Introduction Rapid identification of the causative microorganism is a key element in appropriate antimicrobial therapy of bloodstream infections. Whereas traditional analysis of positive blood cultures requires subculture over at least 16–24 h prior to pathogen identification by, e.g. matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), sample preparation procedures enabling direct MALDI-TOF MS, i.e. without preceding subculture, are associated with additional effort and costs. Hence, we integrated an alternative MALDI-TOF MS approach in diagnostic routine using a short incubation on a solid medium. Materials and methods Positive blood cultures were routinely plated on chocolate agar plates and incubated for 4 h (37 °C, 5% CO 2 ). Subsequently, MALDI-TOF MS using a Microflex LT instrument (Bruker Daltonics) and direct smear method was performed once per sample. For successful identification of bacteria at species level, score cut-off values were used as proposed by the manufacturer (≥2.0) and in a modified form (≥1.5 for MALDI-TOF MS results referring to Gram-positive cocci and ≥1.7 for MALDI-TOF MS results referring to bacteria other than Gram-positive cocci). Further data analysis also included an assessment of the clinical impact of the MALDI-TOF MS result. Results Applying the modified score cut-off values, our approach led to an overall correct species identification in 69.5% with misidentification in 3.4% (original cut-offs: 49.2% and 1.8%, respectively); for Gram-positive cocci, correct identification in 68.4% (100% for Staphylococcus aureus and enterococci, 80% for beta-hemolytic streptococci ) , for Gram-negative bacteria, correct identification in 97.6%. In polymicrobial blood cultures, in 72.7% one of the pathogens was correctly identified. Results were not reliable for Gram-positive rods and yeasts. The approach was easy to implement in diagnostic routine. In cases with available clinical data and successful pathogen identification, in 51.1% our approach allowed an optimized treatment recommendation. Conclusion MALDI-TOF MS following 4 h pre-culture is a valuable tool for rapid pathogen identification from positive blood cultures, allowing easy integration in diagnostic routine and the opportunity of considerably earlier treatment adaptation. [ABSTRACT FROM AUTHOR]

To report the detection of the class D carbapenemase OXA-181 in an MDR clinical Pseudomonas aeruginosa isolate in Germany. Carbapenemase detection was performed by using several phenotypic tests such as the modified Hodge test, a combined disc test with boronic acid, EDTA or cloxacillin, a lysate-based inhibition assays and by PCR for common and rare carbapenemase genes. Antibiotic susceptibilities were determined by broth microdilution. The genetic environment of bla OXA-181 in the clinical P. aeruginosa isolate was characterised by Illumina and MinION sequencing. An multidrug-resistant P. aeruginosa was isolated from a tracheal swab in 2019 and was sent to the German National Reference Centre for multidrug-resistant Gram-negative bacteria for carbapenemase detection. Several phenotypic tests indicated the presence of a carbapenemase which was not inhibited by EDTA nor by boronic acid. PCRs for common and rare carbapenemase genes revealed the presence of a bla OXA-181 gene. WGS data confirmed that the gene was located on the chromosome as part of a Tn 2013 transposon. The genetic organisation of bla OXA-181 has already been described in a P. aeruginosa isolate from England, but both isolates differed significantly in their sequence types (ST111/ST235). Analysis of the genetic environment of the bla OXA-181 gene also revealed high homology to a plasmid from a Klebsiella pneumoniae isolate. To our knowledge, this is the first report of bla OXA-181 in a clinical P. aeruginosa isolate in Germany which emphasises the ongoing spread of yet unusual carbapenemases among different Gram-negative species and therefore complicating their detection in routine laboratories. [ABSTRACT FROM AUTHOR]

Summary: MALDI-TOF MS-based peak differences in oxacillin-resistant Staphylococcus aureus and oxacillin-susceptible S. aureus isolates have been described previously. Unfortunately, these isolates were not isogenic with respect to their mecA gene. Ours is the first to use a SCCmec-harboring parent and a SCCmec-lacking daughter strain, with the same genetic background, to unequivocally rule out strain-specific protein peaks. We could not show differences in the peak profiles within the preset Biotyper settings used for MALDI-TOF-based identification in this pair of SCCmec-harboring parent and SCCmec-lacking daughter strains. [ABSTRACT FROM AUTHOR]

Abstract: The Panton-Valentine leukocidin (PVL) of Staphylococcus aureus plays an important role in the pathogenesis of necrotizing pneumonia and recurrent skin and soft tissue infections. The gene encoding for PVL, lukS/F-PV, is distributed by prophages and can thus spread between isolates. Molecular methods have normally been used to identify lukS/F-PV-positive strains. Recently, however, a matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS)-based method has been described to identify PVL-positive S. aureus strains. The aim of this study was thus to investigate the association of distinct MALDI-TOF MS peaks to the toxin profile in molecularly characterized methicillin-susceptible (MSSA) and methicillin-resistant S. aureus (MRSA) strains harbouring lukS/F-PV. In contrast to the previous results, the MALDI-TOF MS peaks were detected in all 104 recently described molecularly divergent MRSA irrespective of the presence of PVL. Our result indicates that these described peaks seem to be independent of the presence of PVL. [ABSTRACT FROM AUTHOR]

Background: Numerous epidemiologic studies have demonstrated an allergy-protective effect of farm life early in childhood. It has been hypothesized that environmental exposure to microbes may contribute to this effect. Because of their small size and thereby their potential for deposition in lower airways of small children, bacterial spores may be candidates for such allergy-protective effects. Objective: To investigate immune responses elicited by exposure to Bacillus spores in experimental settings. Methods: Animal shed and mattress dusts were analyzed for bacteria and fungi by aerobic and anaerobic growth. Bacillus licheniformis, the most prominent microorganism found in these samples, was investigated with respect to spore specific stimulation of pattern recognition receptors, monocyte-derived dendritic cells and TH-cell polarization in vitro as well as to the prevention of asthma development in a mouse model of allergic asthma. Results: In vitro, B licheniformis spores activated a TH1 cytokine expression profile. In vivo application of these spores resulted in less spore-specific but long-lasting immune activation preventing eosinophilia and goblet cell hyperplasia; however, they provoked an influx of neutrophils in lung tissue of asthmatic mice. Conclusion: Bacterial spores may contribute to the allergy-protective properties of farming environments, but their persistence in the lung causes ongoing immune activation in mouse experiments. [Copyright &y& Elsevier]

Background: Children who grow up in a farming environment show lower levels of atopic sensitization, hay fever, and asthma than children of the same age not living in such an environment. A number of investigations provided good evidence that this is due to an early-life contact with cowsheds, farm animals, and/or consumption of products like raw milk. Also, it had been indicated that microorganisms might have an important effect on the development of allergies, and thus the question arose of which farm microbial organisms, their products, or both might induce or influence allergy-protective mechanisms. Objective: We sought to gain further insight into the potential allergy-protective properties of microbes isolated from the farming environment. Methods: Of a number of bacterial species identified in cowsheds of farms, 2 were selected, isolated, and characterized, namely Acinetobacter lwoffii F78 and Lactococcus lactis G121. The isolates were investigated with regard to their activation of pattern-recognition receptors, the maturation of human monocyte-derived dendritic cells, the upregulation of inflammatory cytokines, the TH1-polarizing Notch ligand expression, and their influence on the allergic phenotype. Results: It is shown that both bacterial isolates were able to reduce allergic reactions in mice, to activate mammalian cells in vitro, and to induce a TH1-polarizing program in dendritic cells. Conclusion: Our data strongly support the hygiene hypothesis, which states that an environment rich in microbiologic structures, such as a farming environment, might protect against the development of allergies. Clinical implications: This work provides the first data on a potential application of cowshed bacteria in allergy protection. [Copyright &y& Elsevier]

Objective: A growing body of research has shown that people with a wide range of psychiatric disorders, including depression, present with alterations of the gut microbiota, although it is unclear if differences may be caused by the action of psychotropic medication. No data exist for patients with borderline personality disorder (BPD), a psychiatric condition that is frequently comorbidly associated with depression.Methods: Twenty-four unmedicated patients and twenty-one age- and sex-matched healthy controls were recruited. Stool samples were frozen at -80 °C within ten minutes after defecation. The V4 region of bacterial 16S ribosomal RNA (rRNA) gene was sequenced on an Illumina platform. Operational taxonomic units (OTUs) were used for further analysis of community structure, alpha- and beta-diversity.Results: There was no significant difference in alpha- and beta-diversity between patients and controls. However, the Bacteroidetes/Firmicutes-ratio was higher in patients, approaching significance (p = 0.06, r = 0.23). Four species were significantly less abundant in BPD patients, namely Pseudoflavonifractor phocaensis (p = 0.003, r = 0.41), Eubacterium coprostanoligenes (p = 0.01, r = 0.34), Anaerotaenia torta (p = 0.01, r = 0.35), and (statistically somewhat weaker) Parabacteroides chongii (p = 0.046, r = 0.26), which correlated with various psychometric scores.Conclusion: Differences in the taxonomic composition may indicate a potential dysbiosis among SCFA-producing bacteria in BPD. Future research is warranted to replicate these findings in independent and larger samples. If confirmed, the results suggest that microbiota-targeted therapies may be a useful adjunct strategy for BPD. [ABSTRACT FROM AUTHOR]

• At the EUCAST susceptibility breakpoint of ≤ 2 mg/L, cefiderocol inhibited 97.2% of 213 randomly selected isolates from intensive care patients with nosocomial infections (set I) and 52 of 59 (88.1%) selected carbapenemase-producing isolates (set II). • Cefiderocol showed potent in vitro activity against Acinetobacter baumannii (highest MIC, 0.25 mg/L). • Cefiderocol also showed good activity against Enterobacterales and Pseudomonas aeruginosa , with about one third of carbapenemase-producing strains of each group requiring concentrations of > 1 mg/L for inhibition. • Among the Enterobacterales, ESBL-positive isolates were less susceptible to cefiderocol than ESBL-negative isolates. • Overall, cefiderocol inhibited 259/272 (95.2%) Gram-negative bacilli at ≤ 2 mg/L. Objectives: Cefiderocol (CID), also known as S-649266, a novel siderophore cephalosporin, possesses potent activity against multidrug-resistant aerobic Gram-negative bacteria (GNB). This study aimed to determine the in vitro activity of CID against two different sets of GNB: i) a random sample of 213 clinical isolates, including 17 extended-spectrum beta-lactamase (ESBL) producers, obtained from intensive care unit patients with nosocomial infections collected during a multicentre surveillance study (set I); and ii) a group of 59 challenge GNB producing various types of carbapenemases (CP; set II). Methods: Minimum inhibitory concentrations (MICs) were determined using the microdilution method according to the standard ISO 20776-1. Iron-depleted medium was used for testing CID. Results: CID inhibited 97.2% of set I isolates at the EUCAST susceptibility breakpoint of ≤ 2 mg/L. The concentrations of CID inhibiting 50% and 90% (MIC 50/90) of the Enterobacterales isolates (n = 146) were 0.12/1.0 mg/L, with ESBL-positive isolates tending to exhibit higher MICs than ESBL-negative isolates to CID. MIC 50/90 values of CID for isolates of the Acinetobacter baumannii group (n = 13) and Pseudomonas aeruginosa (n = 54) were 0.06/0.12 mg/L and 0.12/0.5 mg/L, respectively. Further, CID inhibited 88.1% of set II CP-producing isolates at ≤ 2 mg/L. All seven class D CP-producing Acinetobacter baumannii were inhibited at ≤ 0.25 mg/L. MIC 50/90 values for CP-producing Enterobacterales (n = 30) and Pseudomonas aeruginosa (n = 22) were 1/4 mg/L and 0.5/2 mg/L, respectively. Conclusion: CID showed potent activity against Acinetobacter baumannii , Enterobacterales and Pseudomonas aeruginosa , including CP-producing isolates. Overall, CID inhibited 259 of 272 (95.2%) GNB at ≤ 2 mg/L. [ABSTRACT FROM AUTHOR]

To analyse carbapenemases in Proteus mirabilis and assess the performance of carbapenemase detection assays. Eighty-one clinical P. mirabilis isolates with high-level resistance at least to ampicillin (>32 mg/L) or previous detection of carbapenemases were selected and investigated by three susceptibility testing methods (microdilution, automated susceptibility testing, and disk diffusion), six phenotypic carbapenemase assays (CARBA NP, modified carbapenemase inactivation method [CIM], modified zinc-supplemented CIM, simplified CIM, faropenem, and carbapenem-containing agar), two immunochromatographic assays, and whole-genome sequencing. Carbapenemases were detected in 43 of 81 isolates (OXA-48-like [ n = 13]; OXA-23 [ n = 12]; OXA-58 [ n = 12]; New Delhi metallo-β-lactamase (NDM) [ n = 2]; Verona integron–encoded metallo-β-lactamase (VIM) [ n = 2]; Imipenemase (IMP) [ n = 1]; Klebsiella pneumoniae carbapenemase (KPC) [ n = 1]). Carbapenemase-producing Proteus were frequently susceptible to ertapenem (26/43; 60%), meropenem (28/43; 65%), ceftazidime (33/43; 77%), and some even to piperacillin-tazobactam (9/43; 21%). Sensitivity/specificity of phenotypic tests were 30% (CI: 17–46%)/89% (CI: 75–97%) for CARBA NP, 74% (CI: 60–85%)/82% (CI: 67–91%) for faropenem, 91% (CI: 78–97%)/82% (CI: 66–92%) for simplified CIM, and 93% (CI: 81–99%)/100% (CI: 91–100%) for modified zinc-supplemented CIM. An algorithm for improved detection was developed, which demonstrated sensitivity/specificity of 100% (CI: 92–100%)/100% (CI: 91–100%) on the 81 isolates, and 100% (CI: 29–100%)/100% (CI: 96–100%) in a prospective analysis of additional 91 isolates. Interestingly, several OXA-23-producing isolates belonged to the same clonal lineage reported previously from France. Current susceptibility testing methods and phenotypic tests frequently fail to detect carbapenemases in P. mirabilis , which could result in inadequate antibiotic treatment. In addition, the non-inclusion of bla OXA-23/OXA-58 in many molecular carbapenemase assays further impedes their detection. Therefore, the prevalence of carbapenemases in P. mirabilis is likely underestimated. With the herein proposed algorithm, carbapenemase-producing Proteus can be easily identified. [ABSTRACT FROM AUTHOR]

Abstract: Meticillin-resistant Staphylococcus aureus (MRSA) are endemic in hospitals worldwide and present a major concern in hospital hygiene. The aim of the present study was to investigate the relationship between patients’ MRSA colonization of the body and the frequency of environmental contamination. Twenty-five MRSA-positive hospitalized surgical patients and their environment in isolation rooms were screened on four occasions over a 14-day period. Out of 1099 samples from patients, 330 (30.0%) were MRSA-positive. The median number of MRSA-positive body sites per screening decreased significantly from the 1st (3, range 1–9) to the 14th (2, range 0–9, p=0.011) day of isolation. Contamination was found in 45% of the 100 environmental sampling dates and MRSA was detected in a low proportion of the 1000 environmental surface samples: 105/1000 (10.5%). The number of positive results for each sampling date decreased from the 1st (median 1, range 0–8) to the 14th (median 0, range 0–3, p=0.21) day of isolation. The results show a very strong correlation between the number of MRSA-positive body sites of individual patients and the MRSA contamination of the patient''s hospital room (r=0.700, p<0.001). Pulsed-field gel electrophoresis (PFGE) analysis demonstrated a 98% agreement between patient and environmental samples. MRSA colonization of the groin area correlates most strongly with colonization of the body and environment. Seventy-five of 240 (31%) samples taken in rooms of patients with colonization of the groin were MRSA-positive, whereas only 27 of 760 (3.6%) samples taken in rooms of patients without colonization of the groin produced positive results (odds ratio 12.3; 95% confidence interval, 7.7–20). It is concluded that MRSA patients without colonization of the groin have a relatively low risk of environmental spread of MRSA and thus a reduced risk of transmission. [Copyright &y& Elsevier]

Background Immunopathological concepts have been intensively discussed for schizophrenia. The polyriboinosinic–polyribocytidylic (PolyI:C) mouse model has been well validated to invasively study this disease. The intestinal microbiome exhibits broad immunological and neuronal activities. The relevance of microbiome alterations in the PolyI:C model to human schizophrenia should be explored. Methods Feces of offspring from mice mothers, who were administered to PolyI:C or NaCl (controls) at ED 9, were collected at PND 30 and 180 (PolyI:C and control mice (N = 32 each; half males and females). This was analyzed for bacterial 16S ribosomal DNA (rDNA) using a gut microbiome polymerase chain reaction (PCR) microarray tool. Results Differences were found in species richness of microbiome between animals of different ages (PND 30 and 180), but also between offspring from PolyI:C vs. NaCl treated mothers. In female mice at PND 30, the abundance of Prevotellaceae and Porphyromonadaceae was lower and that of Lactobacillales was higher, whereas in male mice at the same time point the abundance of four families of the Firmicutes phylum (Clostridia vadinBB60 group, Clostridiales Family XIII, Ruminococcaceae and Erysipelotrichaceae) was increased relative to the control group. Limitations No further analyses of cell types or cytokines involved in autoimmune gut and brain processes. Conclusions These finding seem to be similar to microbiome disturbances in patients with schizophrenia. The differential bacterial findings at day 30 (i.e., similar to the prodromal phase in patients with schizophrenia) correspond to the tremendous activation of the immune system with a strong increase in microglial cells which might be responsible for neuroplasticity reduction in cortical areas in patients with schizophrenia. • Ssimilarity of microbiome disturbances in animal model and patients with schizophrenia. • Effects of sexes on microbiome composition in the schizophrenia model. • Bacterial findings at day 30 hint for a tremendous activation of the body immune system responsible for neuroplasticity reduction in schizophrenia. [ABSTRACT FROM AUTHOR]

Purpose: The objective of the ongoing study was to investigate how SARS-CoV-2 infection spread within two hospitals in North Rhine-Westphalia, Germany by testing the employees working in high-risk, intermediate-risk and low-risk-areas for the presence of SARS-CoV-2 IgG antibodies. Presented intermediate results evaluate the first infection period until the end of September 2020.Methods: The study "COVID-19: Hotspot hospital?- Seroprevalence of SARS-CoV-2 antibodies in hospital employees in a secondary care hospital network in Germany " is a prospective, single centre observational cohort study conducted at the St. Vincenz Hospital Datteln with 316 beds. The presented data include one other hospital: St. Laurentius Stift Waltrop, Germany with 172 beds.Results: Between June 2020 and September 2020 we analyzed serum samples of 907 employees which represents 62.1% of all employees. Thirteen employees (1.4%), respectively 13/696 healthcare workers (HCWs) (1.9%) had detectable SARS-CoV-2 IgG antibodies. Among them, 4 (30.8%) were aware of COVID-19 exposure, and 5 (38.5%) reported clinical symptoms. HCWs working in high-risk areas had a seroprevalence rate of 1.6% (1/64), HCWs working in intermediate-risk area 1.7% (11/632) and 0.5% employees (1/211) in low-risk areas with no contact to patients were seropositive.Conclusion: Even if we treated COVID-19 positive patients, we found no clear evidence that infection was transmitted to HCWs in contact to these patients. As knowledge about SARS-CoV-2 transmission evolves, the concept of infection prevention must be continuously reviewed and adapted as needed to keep hospitals a safe place. [ABSTRACT FROM AUTHOR]