Prevalence of third-generation cephalosporin-resistant Enterobacterales colonization on hospital admission and ESBL genotype-specific risk factors: a cross-sectional study in six German university hospitals.

OBJECTIVES: To assess the admission prevalence of third-generation cephalosporin-resistant Enterobacterales (3GCREB) and to assess whether risk factors vary by ß-lactamase genotype. METHODS: Adult patients were recruited within 72 h of admission to general wards of six university hospitals in 2014 and 2015. Rectal swabs were screened for 3GCREB and isolates were analysed phenotypically and genotypically. Patients were questioned on potential risk factors. Multivariable analyses were performed to identify risk factors for 3GCREB colonization and for specific ß-lactamases. RESULTS: Of 8753 patients screened, 828 were 3GCREB positive (9.5%). Eight hundred and thirteen isolates were available for genotyping. CTX-M-15 was the most common ESBL (38.0%), followed by CTX-M-1 (22.5%), CTX-M-14 (8.7%), CTX-M-27 (7.5%) and SHV-ESBL (4.4%). AmpC was found in 11.9%. Interestingly, 18 Escherichia coli isolates were AmpC positive, 12 of which (67%) contained AmpC on a gene of plasmid origin [CMY (n = 10), DHA (n = 2)]. Risk factors for 3GCREB colonization varied by genotype. Recent antibiotic exposure and prior colonization by antibiotic-resistant bacteria were risk factors for all ß-lactamases except CTX-M-14 and CTX-M-27. Travel outside Europe was a risk factor for CTX-M-15 and CTX-M-27 [adjusted OR (aOR) 3.49, 95% CI 2.88-4.24 and aOR 2.73, 95% CI 1.68-4.43]. A previous stay in a long-term care facility was associated with CTX-M-14 (aOR 3.01, 95% CI 1.98-4.59). A preceding hospital stay in Germany increased the risk of CTX-M-15 (aOR 1.27, 95% CI 1.14-1.41), while a prior hospital stay in other European countries increased the risk of SHV-ESBL colonization (aOR 3.85, 95% CI 1.67-8.92). CONCLUSIONS: The detection of different ESBL types is associated with specific risk factor sets that might represent distinct sources of colonization and ESBL-specific dissemination routes.

Clinical assessment of a foam dressing containing growth factor-enhancing hydrated polyurethanes.

OBJECTIVE: This study assesses a novel dressing concept in venous leg ulcer (VLU) patients. It is based on boosting endogenous growth factor activities synthesised by functional granulation tissue. METHODS: Patients received treatment for eight weeks with a hydrated polyurethane-containing foam dressing plus concomitant compression therapy. Wound area reduction (WAR), percentage of wounds achieving a relative WAR of ≥40% and ≥60%, wound pain ratings for the last 24 hours and at dressing changes, EQ-5D Quality of Life questionnaire data, dressing handling and safety parameters were recorded. RESULTS: There were 128 patients who received treatment and data for 123 wound treatment courses were documented. Wound area size decreased from 13.3±9.8cm2 to 10.5±12.2cm2 at week eight and median relative WAR was 48.8%. At week eight, a relative WAR ≥40% was reached by 54.5% of the wounds, 41.5% reached a relative WAR of ≥60% and complete healing was observed in 13.5% of wounds. Median wound pain ratings (last 24 hours before dressing change) declined significantly from 30 to 15.5 (100 visual analogue scale [VAS], p=0.0001) and pain at dressing changes from 30 to 12.5 (p≤0.0001). The EQ-5D VAS rating increased from 58.4±19.2mm to 63.1±19.1mm (p=0.0059). CONCLUSION: This clinical assessment shows that the concept of boosting endogenous growth factors through hydrated polyurethanes has the potential to accelerate WAR in VLU patients while decreasing pain levels and improving quality of life parameters.

Incidence of infections due to third generation cephalosporin-resistant Enterobacteriaceae - a prospective multicentre cohort study in six German university hospitals.

Background: Infections caused by third generation cephalosporin-resistant Enterobacteriaceae (3GCREB) are an increasing healthcare problem. We aim to describe the 3GCREB infection incidence and compare it to prevalence upon admission. In addition, we aim to describe infections caused by 3GCREB, which are also carbapenem resistant (CRE). Methods: In 2014-2015, we performed prospective 3GCREB surveillance in clinically relevant patient specimens (screening specimens excluded). Infections counted as hospital-acquired (HAI) when the 3GCREB was detected after the third day following admission, otherwise as community-acquired infection (CAI). Results: Of 578,420 hospitalized patients under surveillance, 3367 had a 3GCREB infection (0.58%). We observed a similar 3GCREB CAI and HAI incidence (0.28 and 0.31 per 100 patients, respectively). The most frequent pathogen was 3GCR E. coli, in CAI and HAI (0.15 and 0.12 per 100 patients). We observed a CRE CAI incidence of 0.006 and a HAI incidence of 0.008 per 100 patients (0.014 per 1000 patient days). Conclusions: Comparing the known 3GCREB admission prevalence of the participating hospitals (9.5%) with the percentage of patients with a 3GCREB infection (0.58%), we conclude the prevalence of 3GCREB in university hospitals to be about 16 times higher than suggested when only patients with 3GCREB infections are considered. Moreover, we find the HAI and CAI incidence caused by CRE in Germany to be relatively low.

Gender differences in antibiotic prescribing in the community: a systematic review and meta-analysis.

OBJECTIVES: Determinants of inappropriate antibiotic prescription in the community are not clearly defined. The objective of this study was to perform a systematic review and meta-analysis evaluating gender differences in antibiotic prescribing in primary care. METHODS: All studies analysing antibiotic prescription in primary care were eligible. PubMed and MEDLINE entries with publication dates from 1976 until December 2013 were searched. The primary outcomes were the incidence rate ratio (IRR) (measured as DDD/1000 inhabitants/day) and the prevalence rate ratio (PRR) (measured as prevalence rate/1000 inhabitants) of antimicrobial prescription, stratified by gender, age and antibiotic class. Random-effects estimates of the IRR and PRR and standard deviations were calculated. RESULTS: Overall, 576 articles were reviewed. Eleven studies, comprising a total of 44 333 839 individuals, were included. The studies used data from prospective national (five studies) or regional (six studies) surveillance of community pharmacy, insurance or national healthcare systems. Women were 27% (PRR 1.27 ±â€Š0.12) more likely than men to receive an antibiotic prescription in their lifetimes. The amount of antibiotics prescribed to women was 36% (IRR 1.36 ±â€Š0.11) higher than that prescribed for men in the 16 to 34 years age group and 40% (IRR 1.40 ±â€Š0.03) greater in the 35 to 54 years age group. In particular, the amounts of cephalosporins and macrolides prescribed to women were 44% (IRR 1.44 ±â€Š0.30) and 32% (IRR 1.32 ±â€Š0.15) higher, respectively, than those prescribed for men. CONCLUSIONS: This meta-analysis shows that women in the 16 to 54 years age group receive a significantly higher number of prescriptions of cephalosporins and macrolides in primary care than men do. Prospective studies are needed to address reasons for gender inequality in prescription and to determine whether a difference in adverse events, including resistance development, also occurs.

STROBE-AMS: recommendations to optimise reporting of epidemiological studies on antimicrobial resistance and informing improvement in antimicrobial stewardship.

OBJECTIVES: To explore the accuracy of application of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) tool in epidemiological studies focused on the evaluation of the role of antibiotics in selecting resistance, and to derive and test an extension of STROBE to improve the suitability of the tool in evaluating the quality of reporting in these area. METHODS: A three-step study was performed. First, a systematic review of the literature analysing the association between antimicrobial exposure and acquisition of methicillin-resistant Staphylococcus aureus and/or multidrug-resistant Acinetobacter baumannii was performed. Second, articles were reviewed according to the STROBE checklist for epidemiological studies. Third, a set of potential new items focused on antimicrobial-resistance quality indicators was derived through an expert two-round RAND-modified Delphi procedure and tested on the articles selected through the literature review. RESULTS: The literature search identified 78 studies. Overall, the quality of reporting appeared to be poor in most areas. Five STROBE items, comprising statistical analysis and study objectives, were satisfactory in <25% of the studies. Informative abstract, reporting of bias, control of confounding, generalisability and description of study size were missing in more than half the articles. A set of 21 new items was developed and tested. The new items focused particularly on the study setting, antimicrobial usage indicators, and patients epidemiological and clinical characteristics. The performance of the new items in included studies was very low (<25%). CONCLUSIONS: Our paper reveals that reporting in epidemiological papers analysing the association between antimicrobial usage and development of resistance is poor. The implementation of the newly developed STROBE for antimicrobial stewardship (AMS) tool should enhance appropriate study design and reporting, and therefore contribute to the improvement of evidence to be used for AMS programme development and assessment.

Altering gene expression by aminocoumarins: the role of DNA supercoiling in Staphylococcus aureus.

BACKGROUND: It has been shown previously that aminocoumarin antibiotics such as novobiocin lead to immediate downregulation of recA expression and thereby inhibit the SOS response, mutation frequency and recombination capacity in Staphylococcus aureus. Aminocoumarins function by inhibiting the ATPase activity of DNA gyrase subunit B with a severe impact on DNA supercoiling. RESULTS: Here, we have analysed the global impact of the DNA relaxing agent novobiocin on gene expression in S. aureus. Using a novobiocin-resistant mutant, it became evident that the change in recA expression is due to gyrase inhibition. Microarray analysis and northern blot hybridisation revealed that the expression levels of a distinct set of genes were increased (e.g., recF-gyrB-gyrA, the rib operon and the ure operon) or decreased (e.g., arlRS, recA, lukA, hlgC and fnbA) by novobiocin. The two-component ArlRS system was previously found to decrease the level of supercoiling in S. aureus. Thus, downregulation of arlRS might partially compensate for the relaxing effect of novobiocin. Global analysis and gene mapping of supercoiling-sensitive genes did not provide any indication that they are clustered in the genome. Promoter fusion assays confirmed that the responsiveness of a given gene is intrinsic to the promoter region but independent of the chromosomal location. CONCLUSIONS: The results indicate that the molecular properties of a given promoter, rather than the chromosomal topology, dictate the responsiveness to changes in supercoiling in the pathogen Staphylococcus aureus.

Production of capsular polysaccharide does not influence Staphylococcus aureus vancomycin susceptibility.

BACKGROUND: Diverse mechanisms (increased cell wall thickness, low cross linking, decreased autolysis, etc.) have been reported for Staphylococcus aureus strains with intermediate vancomycin susceptibility (VISA). This study was conducted to identify common mechanisms responsible for decreased vancomycin susceptibility in a VISA strain pair. RESULTS: Transcriptional profiling of the clinical heterogeneous VISA isolate SA137/93A and its spontaneous homogeneous mutant strain SA137/93G pointed to an increased capsule production in the strain pair compared to a susceptible control. Furthermore, transcript quantification of the gene cap5E, which is essential for capsule biosynthesis, revealed elevated levels in the VISA strains SA137/93A, SA137/93G and Mu50 in comparison with susceptible strains Reynolds, Newman and SA1450/94. The increased expression was observed in bacteria from exponential as well as stationary growth phase. However, suppression of type 5 capsule formation by expression of antisense RNA did not increase vancomycin susceptibility in the VISA strain SA137/93G. Likewise, construction of inducible mutants of S. aureus Newman or repair of capsule biosynthesis of S. aureus HG001 and S. aureus 1450/94 did not influence resistance to vancomycin. Furthermore, purified type 5 polysaccharide did not protect indicator strains from the action of vancomycin. CONCLUSIONS: The VISA strain tested in this study displayed an increased production of type 5 capsular polysaccharide. However, the production of capsule material did not protect strain SA137/93G and three vancomycin sensitive strains in the presence of vancomycin and thus is not part of the resistance mechanism; however it may represent a by-product of VISA life style that is often characterized by a high sigma factor B activity.

Opposing effects of aminocoumarins and fluoroquinolones on the SOS response and adaptability in Staphylococcus aureus.

OBJECTIVES: RecA is the key enzyme involved in DNA repair, recombination and induction of the SOS response and is central to the development of antibiotic resistance. Here we assessed the interaction of two different gyrase inhibitors, ciprofloxacin (a fluoroquinolone) and novobiocin (an aminocoumarin), on RecA activity and the SOS response in Staphylococcus aureus. METHODS: The influence of different gyrase inhibitors on the SOS response of S. aureus (including recA and lexA mutants) was analysed by northern blot analysis, real-time RT-PCR, western blot analysis and promoter activity assays. Recombination as well as mutation frequencies were determined for the different antibiotic combinations. RESULTS: We verified that ciprofloxacin leads to RecA activation and therefore induction of the SOS response. In contrast, novobiocin treatment resulted in an inhibition of recA transcription independent of LexA. When novobiocin and ciprofloxacin were added simultaneously, recA was reduced to the same level as with novobiocin alone. In combination, novobiocin also partially reduces the ciprofloxacin-mediated induction of the LexA target gene umuC (error-prone polymerase). Apart from reducing recA and umuC expression, novobiocin also inhibited the frequency of recombination, mutation and the formation of non-haemolytic variants. CONCLUSION: In summary, aminocoumarins inhibit recA expression in S. aureus and probably delay the process of developing antibiotic resistance and gene transfer. A clinical re-evaluation of these compounds as well as designing more applicable derivatives should be considered.

Candidate genes for physical performance in the horse.

Intense selection for speed, endurance or pulling power in the domestic horse (Equus caballus) has resulted in a number of adaptive changes in the phenotype required for elite athletic performance. To date, studies in humans have revealed a large number of genes involved in elite athletic performance, but studies in horses are rare. The horse genome assembly and bioinformation tools for genome analyses have been used to compare human performance genes with their equine orthologues, both to retrieve pathways for these genes and to investigate their chromosomal distribution. In this review, 28 candidate genes for equine performance are presented that have polymorphisms associated with human elite athletic performance and may have impact on athletic performance in horses. A significant accumulation of candidate genes was found on horse chromosomes 4 and 12. Genes involved in pathways for focal adhesion, regulation of actin cytoskeleton, neuroactive ligand-receptor interaction, and calcium signalling were over-represented. Genome-wide association studies for athletic performance in horses may benefit from the strong conserved synteny of the chromosomal arrangement of genes in humans and horses.

Examiner differences in the assessment of different malocclusions.

BACKGROUND: In the current discussion about ensuring treatment quality and reducing costs in the health sector, indication systems with which to determine the need for a treatment and the success of therapy are increasingly being used in orthodontics. These indication systems require the objective evaluation of malocclusions. Our objective was to determine the examiner reliability in the assessment of various malocclusions. MATERIALS AND METHODS: In 180 adults (64 male, 116 female, aged 20-49) from the population-based Study of Health in Pomerania (SHIP), malocclusions were recorded clinically and on models by calibrated examiners. An experienced orthodontist conducted the clinical examination. Another orthodontically-experienced examiner analyzed the models. To compare the model examiners, two examiners with varying degrees of orthodontic experience evaluated 60 of the 180 models as well (29 male, 31 female). One of the model examiners repeated the assessment of 60 models at a later time (intra-individual comparison). RESULTS AND CONCLUSIONS: Reliability amongst the examiners depended on which malocclusions were judged: crowding and contact point displacement showed little agreement, while cross bite, edge-to-edge bite, deep bite and enlarged overjet revealed greater agreement. Comparison between the clinical examination and model analysis (kappa median 0.57) revealed the greatest differences between the examiners. Comparison of the three model examiners also showed differences. The contrast to the orthodontically least experienced examiner was greater (kappa median 0.61 and 0.62) than the divergence between the two orthodontically more experienced examiners (kappa median 0.70). The intra-individual examiner comparison revealed the smallest differences (kappa median 0.82).

Influence of examiner differences on KIG-classification when assessing malocclusions.

OBJECTIVE: Indication systems such as the German KIG system (Kieferorthopädische Indikationsgruppen = Orthodontic Indication Groups) presuppose the objective assessment of underlying malocclusions. In this survey, we aimed to investigate the degree of agreement among the findings of several examiners in the assessment of different malocclusions and their classification according to the KIG system. SUBJECTS AND METHODS: Calibrated examiners assessed in the clinical evaluation and on plaster models orthodontic malocclusions in 180 adults (aged 20-49, 64 male, 116 female) from the population-based Study of Health in Pomerania (SHIP). Clinical examination was carried out by an experienced orthodontist, and the plaster models were also analysed by an examiner experienced in orthodontics. To compare inter- and intra-individual model examiners, we had two examiners with differing orthodontic experience carry out additional analyses of 60 of the 180 models (29 male, 31 female). RESULTS: The examiner differences yielded various KIG classifications and hence different assessments (i. e., whether KIG case-costs should be borne by health insurance). The comparison "clinical examination versus model analysis" revealed differences regarding 16.7% of the study participants in the assessment of whether the expense would be borne by the statutory health insurance fund. At 5.0-8.3%, the number of participants whose assessments had differed was much smaller in the inter-individual comparison of model-examiners and was smallest (at 3.3-6.7%) when comparison was made between intra-individual assessments (by a sole examiner). With regard to overall malocclusion assessment, the greatest examiner differences were again revealed when comparing the clinical examination with the model analysis (median kappa 0.57). The model-examiner comparison revealed larger differences among examiners with less orthodontic experience (median kappa 0.61 and 0.62) than the comparison between examiners with orthodontic experience (median kappa 0.70). CONCLUSIONS: There can occasionally be considerable examiner differences in the classification of participants according to orthodontic indication groups and hence varying assessments of whether such persons are KIG cases or not. Various means of data collection (clinical evaluation-plaster models) in the assessment of malocclusions by multiple examiners and by those with little orthodontic experience may negatively influence agreement among examiners.