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Tax aggressiveness presents nontax risks to firms' cash flow. Evaluating these risks requires information beyond the accounting function's expertise, resulting in high processing costs to acquire and integrate risk information relevant to tax strategies. Managers can rationally adapt by making assumptions about risk information, potentially resulting in decision biases when evaluating the risk-reward tradeoff of tax aggressiveness. Using a novel regulatory setting in the U.S. insurance industry, I examine whether the adoption of mandated enterprise risk assessments updates managers' prior beliefs about the nontax risks of tax aggressiveness. I find that as regulation requires managers to accept processing costs to acquire and integrate risk information, managers learn about previously underestimated nontax risks and significantly reduce tax aggressiveness. Results suggest that absent firm-wide internal risk information, managers can use aggressive tax positions without fully considering nontax risks. Data Availability: Data used in this study are available from public sources identified in the paper. JEL Classifications: G22; G32; H25; M41. [ABSTRACT FROM AUTHOR]

For some time now, Solvency II requires that insurance companies calculate minimum capital requirements to face the risk of insolvency, either in accordance with the Standard Formula or using a full or partial Internal Model. An Internal Model must be based on a market-consistent valuation of assets and liabilities at a 1-year time span, where a real-world probabilistic structure is used for the first year of projection. In this paper, we describe the major risks of a non-life insurance company, i.e. the non-life underwriting risk and market risk, and their interactions, focusing on the non-life premium risk, equity risk, and interest rate risk. This analysis is made using some well-known stochastic models in the financial-actuarial literature and practical insurance business, i.e. the Collective Risk Model for non-life premium risk, the Geometric Brownian Motion for equity risk, and a real-world version of the G2++ Model for interest rate risk, where parameters are calibrated on current and real market data. Finally, we illustrate a case study on a single-line and a multi-line insurance company in order to see how the risk drivers behave in both a stand-alone and an aggregate framework. [ABSTRACT FROM AUTHOR]

• Predictive performance of antimicrobial resistance in Staphylococcus aureus varies by database and machine learning model. • LightGBM performs better in predicting resistance of ORSA compared with all Staphylococcus aureus and OSSA. • Specific and overlapping mass spectra features predict mecA and tier 1 antibiotic resistance. • Transfer learning enhances resistance prediction of some antibiotics using institutional data. • MALDI-TOF MS with machine learning rapidly predicts mecA and antimicrobial resistance in Staphylococcus aureus. The use of matrix-assisted laser desorption/ionisation-time-of-flight mass spectra (MALDI-TOF MS) with machine learning (ML) has been explored for predicting antimicrobial resistance. This study evaluates the effectiveness of MALDI-TOF MS paired with various ML classifiers and establishes optimal models for predicting antimicrobial resistance and the presence of mecA gene among Staphylococcus aureus. Antimicrobial resistance against tier 1 antibiotics and MALDI-TOF MS of S. aureus were analysed using data from the Database of Resistance against Antimicrobials with MALDI-TOF Mass Spectrometry (DRIAMS) and one medical centre (CS database). Five ML classifiers were used to analyse performance metrics. The Shapley value quantified the predictive contribution of individual features. The LightGBM demonstrated superior performance in predicting antimicrobial resistance for most tier 1 antibiotics among oxacillin-resistant S. aureus (ORSA) compared with all S. aureus and oxacillin-susceptible S. aureus (OSSA) in both databases. In DRIAMS, Multilayer Perceptron (MLP) was associated with excellent predictive performance, expressed as accuracy/AUROC/AUPR, for clindamycin (0.74/0.81/0.90), tetracycline (0.86/0.87/0.94), and trimethoprim-sulfamethoxazole (0.95/0.72/0.97). In the CS database, Ada and Light Gradient Boosting Machine (LightGBM) showed excellent performance for erythromycin (0.97/0.92/0.86) and tetracycline (0.68/0.79/0.86). Mass-to-charge ratio (m/z) features of 2411–2414 and 2429–2432 correlated with clindamycin resistance, whereas 5033–5036 was linked to erythromycin resistance in DRIAMS. In the CS database, overlapping features of 2423–2426, 4496–4499, and 3764–3767 simultaneously predicted the presence of mecA and oxacillin resistance. The predictive performance of antimicrobial resistance against S. aureus using MALDI-TOF MS depends on database characteristics and the ML algorithm selected. Specific and overlapping mass spectra features are excellent predictive markers for mecA and specific antimicrobial resistance. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper discusses the use of modelling techniques for the purpose of risk management within life insurers. The key theme of the paper is that life insurance is long-term business and carries with it long-term risks, yet much of modern actuarial risk management is focussed on short-term modelling approaches. These typically include the use of copula simulation models within a 1-year Value-at-Risk (VaR) framework. The paper discusses the limitations inherent within the techniques currently used in the UK and discusses how the focus of the next generation of actuarial models may be on long-term stochastic projections. The scope of the paper includes a discussion of how existing techniques, together with new approaches, may be used to develop such models and the benefits this can bring. The paper concludes with a practical example of how a long-term stochastic risk model may be implemented. [ABSTRACT FROM AUTHOR]

In this paper, we construct new valuation schemes for the liabilities and economic capital of insurance companies. Specifically, we first build a 'SAHARA' valuation framework based on Symmetric Asymptotic Hyperbolic Absolute Risk Aversion utility functions. Then, we construct a 'SAHARA-CPT' framework that incorporates the previous utility function as a value function and that is based on Cumulative Prospect Theory. The process used for assessing a life insurance company's own funds consists in replacing the market-consistent parametrization with a utility-consistent parametrization that accounts for the risk aversion of the market and the long-term duration of the company's commitments. Our illustrations show that this approach leads to a lower value of the Own Risk and Solvency Assessment and to a lower volatility of own funds. The framework that is based on cumulative prospect theory has the advantage over the expected utility theory framework that it considers a precautionary overweighting of extreme events, as a tradeoff for additional model complexity. [ABSTRACT FROM AUTHOR]

We consider various aspects of longevity trend risk viewed through the prism of a finite time window. We show the broad equivalence of value-at-risk (VaR) capital requirements at a p-value of 99.5% to conditional tail expectations (CTEs) at 99%. We also show how deferred annuities have higher risk, which can require double the solvency capital of equivalently aged immediate anuities. However, results vary considerably with the choice of model and so longevity trend-risk capital can only be determined through consideration of multiple models to inform actuarial judgement. This model risk is even starker when trying to value longevity derivatives. We briefly discuss the importance of using smoothed models and describe two methods to considerably shorten VaR and CTE run times. [ABSTRACT FROM AUTHOR]

Introduction: A fast and accurate determination of methicillin resistance in Staphylococcus aureus strains is vital. This study aimed to compare the sensitivity and specificity of the cefoxitin disc diffusion (CDD) test and BD Phoenix automated system considering mecA/mecC positivity as the gold standard and to investigate the presence of Panton-Valentine leukocidin (PVL) toxin gene, a crucial virulence factor of S. aureus strains. Materials and Methods: Overall, 179 Staphylococcus aureus strains from various clinical samples were included. Antibiotic sensitivity was tested using the Phoenix automated system and by applying the Kirby-Bauer disc diffusion method for cefoxitin (30 μg). The mecA, mecC, and PVL presence was determined using the conventional multiplex polymerase chain reaction method. mecA/mecC positivity was considered as the gold standard. Statistical analysis was performed using SPSS 15.0 for Windows (Chicago, IL, USA). Results: Overall, 91 strains (50.8%) were mecA positive and identified as methicillin resistant Staphylococcus aureus (MRSA). No isolates containing the mecC gene were detected. The Phoenix automated system falsely identified six methicillin-sensitive S. aureus (MSSA) isolates, which were mecA and mecC negative as MRSA. The sensitivity and specificity of the CDD test were found to be 100% in determining MRSA, and the sensitivity and specificity the Phoenix automated system were 100% and 93.2%, respectively. The PVL positivity rate in MRSA and MSSA strains was 6.5% and 7.4%, respectively. All PVL-positive strains were isolated from the skin and soft tissues. Conclusion: The CDD test is a reliable method for routine procedures. Methicillin-sensitive strains can be determined as MRSA via the Phoenix automated system. Nevertheless, mecC-controlled MRSA should not be excluded from methods used for determining methicillin resistance. Panton-Valentine leukocidin toxin gene should be determined to enable clinicians to understand the infection severity.

Introduction: Antibiotics are lifesaving compounds that have been successful for decades. However, many pathogenic bacteria are becoming resistant to them. Cross-resistance of the macrolide-lincosamide-streptogramin B (MLSB) antibiotic classes is a major cause of increased morbidity. This study appraises the phenotypic and genotypic distribution of inducible clindamycin resistance among methicillin-resistant Staphylococcus aureus (MRSA) isolates. Materials and Methods: Erythromycin-induced resistance to clindamycin antibiotics among MRSA isolates was verified phenotypically using the Double-disk diffusion test (D-test) and genotypically by the polymerase chain reaction. Results: All MRSA isolates were resistant to erythromycin. The prevalence of iMLSB (iMLSB: inducible macrolide-lincosamide-streptogramin B) phenotype was 23.7% (9/38), macrolide streptogramin (MS) phenotype 47.4% (18/38), and cMLSB (cMLS: constitutive macrolide-lincosamide-streptogramin) phenotype 28.9% (11/38) of the isolates. The nine isolates with the iMLSB phenotype were tested for the presence of the erythromycin ribosomal methylase (erm) gene. The ermA gene was detected in five (55.6%) isolates, the ermB gene in two (22.2%) isolates, and the ermC gene in two (22.2%) isolates. Conclusion: The erm-positive isolates expressed the iMLSB phenotype, and the ermA gene was predominant. We showed that the cMLSB phenotype was prevalent among the MRSA isolates, signifying the possibility of achieving a good therapeutic outcome when clindamycin is used. The observed distribution of the erm gene explored here gives credence to the adequacy of the D-test in monitoring and testing for potential clindamycin treatment failures.

The main goal of the paper is the evaluation of the Solvency Need SN(h), where h is the maximal duration of the insurance contracts that we will consider. We define it as the quantile of R(h, S) − 𝔼[R(h, S)], where R(h, S) is the reserve introduced in Nichil and Vallois (Insurance: Mathematics and Economics 66:29–43, 2016) and S := (Sx, x ⩾ 0) is a systemic risk. We prove that the normalized reserve converges in distribution, as h → + ∞, to the sum of a Gaussian RV and an independent RV which is an integral of a function of the systemic risk. In the case of mortgage guarantee we can go further in the description of the non-Gaussian RV and we propose three numerical schemes to estimate SN(h) when h is large and we compare the results of simulation. [ABSTRACT FROM AUTHOR]

Currently multiresistant Staphylococcus aureus is one common cause of infections with high rates of morbidity and mortality worldwide, which directs scientific endeavors in search for novel antimicrobials. In this study, nine extracts from Bidens pilosa (root, stem, flower and leaves) and Annona crassiflora (rind fruit, stem, leaves, seed and pulp) were obtained with ethanol: water (7:3, v/v) and their in vitro antibacterial activity evaluated through both the agar diffusion and broth microdilution methods against 60 Oxacillin Resistant S. aureus (ORSA) strains and against S. aureus ATCC6538. The extracts from B. pilosa and A. crassiflora inhibited the growth of the ORSA isolates in both methods. Leaves of B. pilosa presented mean of the inhibition zone diameters significantly higher than chlorexidine 0.12% against ORSA, and the extracts were more active against S. aureus ATCC (p < 0.05). Parallel, toxicity testing by using MTT method and phytochemical screening were assessed, and three extracts (B. pilosa, root and leaf, and A. crassiflora, seed) did not evidence toxicity. On the other hand, the cytotoxic concentrations (CC50 and CC90) for other extracts ranged from 2.06 to 10.77 mg/mL. The presence of variable alkaloids, flavonoids, tannins and saponins was observed, even though there was a total absence of anthraquinones. Thus, the extracts from the leaves of B. pilosa revealed good anti-ORSA activity and did not exhibit toxicity.

Portfolios of traditional participating life insurance contracts with year-to-year (cliquet-style) guarantees are under pressure in the current situation of persistently low interest rates when valued in a market consistent valuation framework. For a portfolio with a fixed technical interest rate it has been shown in Reuß et al. (Innov Quant Risk Manag 99:185-208, 2015) that product designs with alternative guarantees are able to reduce the insurers risk and increase capital efficiency. The objective of this paper is to analyze interactions between new contracts and an existing book of insurance contracts. We consider an insurer that has built up a portfolio in the past under changing guaranteed interest rates and market conditions. Then, we analyze different new business strategies for this insurer and the resulting risk exposure and capital requirement. We show that-if all contracts are covered by the same pool of assets-switching to carefully designed participating contracts with alternative guarantees is typically preferable to a runoff scenario and can substantially reduce financial risk in future years. [ABSTRACT FROM AUTHOR]

Introduction: Methicillin resistant Staphylococcus aureus has emerged as an important pathogen in nosocomial and community acquired infections. Accurate and rapid identification of MRSA in clinical specimens is essential for timely decision of effective antimicrobial chemotherapy. Aim: The present study was conducted to compare efficacy of four conventional phenotypic methods, with mec- A based polymerase chain reaction (PCR) for MRSA identification. Materials and Methods: Methicillin resistance was determined in 200 S.aureus isolates by oxacillin disc diffusion, cefoxitin disc diffusion, Oxacillin Resistance Screening Agar and E-test. The results were compared with mec-A based PCR. Results: Among 200 S.aureus isolates 62 (31%) were positive for mec-A gene by PCR. Cefoxitin disc diffusion, Oxacillin Resistance Screening Agar and E-test showed 100% specificity. Oxacillin disc diffusion had lowest sensitivity (82.5%) and specificity (98.5%) among all. The conventional methods take more time than PCR for diagnosing MRSA. Linezolid, Vancomycin & Dalfopristin were the highly sensitive drugs against MRSA isolates. Conclusion: Cefoxitin disc diffusion, is rapid, simple and cheaper, hence can be used routinely as an alternative to PCR for detection of MRSA in resource constraint laboratories.

Abstract: The decrease in susceptibility to glycopeptides by oxacillin resistant Staphylococcus aureus (ORSA) has become a current problem. Objective: To evaluate susceptibility to glycopeptides in ORSA strains isolated in the University Hospital, Maracaibo, during the first quarter of 2010. Methods: Oxacillin resistance of the ORSA strains was verified by diffusion on agar (oxacillin 1 µg and cefoxitin 30 µg, OXOID®), a screening test in Müeller Hinton agar with 6 µg/mL of vancomycin (Sigma®), and E-test® for minimum inhibitory concentration (MIC) for oxacillin, detection of PBP2a (Latex, OXOID®) and the mecA gene by polymerase chain reaction (PCR). In addition, susceptibility to glycopeptides was determined by disk diffusion (teicoplanin, 30 µg OXOID®), MIC by E-test®, screening test in Müeller-Hinton agar with teicoplanin (5 µg/ml) or in brain heart infusion agar with vancomycin (6 µg/mL), glycopeptide hetero-resistance detection by GDR E-test® and detection of the vanA gene using PCR. Results: No ORSA strain was isolated with intermediate resistance (VISA or hVISA), nor with high-level resistance to glycopeptides. Conclusions: Locally, there is no incidence of ORSA strains resistant to glycopeptides; therefore, these antibiotics continue to be useful for treating infections produced by this important pathogen. Resumen: La disminución de la susceptibilidad a los glicopéptidos por parte de Staphylococcus aureus oxacilina resistente (SAOR) se ha convertido en una problemática actual. Objetivo: Evaluar la susceptibilidad a los glicopéptidos en cepas SAOR aisladas en el Hospital Universitario de Maracaibo, durante el primer trimestre del 2010. Métodos: a las cepas SAOR se le verificó la resistencia a oxacilina por difusión en agar (oxacilina 1 µg y cefoxitina 30 µg, OXOID®), prueba de descarte en agar Müeller Hinton con 6 µg/mL de oxacilina (Sigma®), concentración inhibitoria mínima (CIM) a oxacilina mediante E-test®, detección de PBP2a (látex, OXOID®) y del gen mecA por reacción en cadena de la polimerasa (PCR). Se determinó, además, la susceptibilidad a glicopéptidos por difusión del disco (teicoplanina 30 µg, OXOID®), CIM por E-test®, prueba de descarte en agar Müeller-Hinton con teicoplanina (5 µg/mL, Sigma®) o infusión cerebro corazón con vancomicina (6 µg/mL, Sigma®), detección de hetero-resistencia (GDR E-test®) y la detección del gen vanA mediante PCR. Resultados: no se aisló ninguna cepa SAOR con resistencia intermedia (VISA o hVISA), ni tampoco, con resistencia de alto nivel a glicopéptidos (SAVR). Conclusiones: En la localidad, no existe incidencia de cepas SAOR resistentes a los glicopéptidos, por lo que estos antibióticos continúan siendo de utilidad en la terapéutica de las infecciones producidas por este importante patógeno.

Background and Objectives: The global spread of methicillin resistant Staphylococcus aureus (MRSA) constitutes one of the most serious contemporary challenges to the treatment of hospital-acquired infections. We aimed to screen and assess the antibiotic susceptibility pattern of Staphylococcus aureus isolated from clinical specimens in local hospitals of Northern province in Jordan. Materials and Methods: Staphylococcus aureus was isolated and identified using standard methods from various clinical specimens of different infected body sites from 358 patients during the period from January 2005 to November 2008. Results: Our analysis showed that 31.6% of S. aureus infections were MRSA, while 31% were multidrug resistance (MDR) and 42.7% were Oxacillin-resistant (ORSA). Most of these strains were isolated from wound specimens. All isolates were susceptible to vancomycin (100%). They were also susceptible to chloramphenicol, linezolid, nitrofurantoin, rifampicin and teicoplanin (>80%), but showed resistance to erythromycin and penicillin. Conclusion: Vancomycin was the most effective antimicrobial agent against S. aureus. We recommend regular surveillance of hospital associated infections and monitoring antibiotic sensitivity pattern and strict drug policy for antibiotics used within and outside the hospital environments.

Bacterial counts were made of catheter insertion site and of catheter tips to help determine risk factors associated with catheterization of the jugular and subclavian veins. Among the 116 patients included in this study, 69% had central venous catheters (CVC) in the subclavian vein. Seven or more days catheterization (p=0.001) and >3 invasive devices (p=0.01) were infection risk factors associated with catheterization of the jugular vein. More than half of the patients presented high colony counts at the insertion site (>200 CFU/20 cm²) and 27% of the catheter tips were contaminated. The risk factors associated with contaminated catheter tips were >14 days hospital stay (p=0.02), >7 days catheterization (p=0.01) and antibiotic therapy (p=0.04). Coagulase-negative staphylococci (CoNS) and Staphylococcus aureus were the most common microorganisms at the insertion site (78%) and in the catheter tip (94%). Five patients presented sepsis (4.1%), four caused by Staphylococci and one by GNB. Twelve patients had the same microorganisms at the insertion site and catheter tip. We found a high prevalence of ORSA (62.5%) and ORCoNS (57.1%) in catheter tips. The high counts of staphylococci, including ORSA and ORCoNS, at the insertion site, and the significant association of this colonization with catheter tip contamination, indicate that the skin is an important reservoir of microorganisms associated with catheter-related bloodstream infection (CR-BSI). Health professionals should be aware of this potential source of infection at the CVC insertion site.

Arbekacin is an aminoglycoside used in Japan for treating infections caused by gentamicin and oxacillin-resistant S. aureus (ORSA). The objective of this study was to determine the in vitro antimicrobial activity of arbekacin against 454 clinical isolates of ORSA. The isolates were consecutively collected between January and July, 2000, from patients hospitalized in 8 Brazilian medical centers. The antimicrobial susceptibility testing was performed by disk diffusion method according to NCCLS recommendations. The vast majority of the isolates, 453 strains (99.8%), were considered susceptible to arbekacin based on the criteria proposed by the Requirements for Antibiotic Products of Japan. Only 1 isolate (0.2%) was classified as resistant. On the other hand, high rates of resistance were demonstrated for other aminoglycosides, such as gentamicin (97.6% resistance) and amikacin (97.0% resistance). Resistance rate was also high for ciprofloxacin (98.0%). All isolates were considered susceptible to vancomycin. The excellent in vitro antimicrobial activity of arbekacin demonstrated in this study indicates that this antimicrobial agent may play an important role in the treatment of severe ORSA infections, especially those that show poor clinical response with vancomycin monotherapy. Since the aminoglycosides should not be used as monotherapy to treat Gram positive infections, further studies evaluating in vitro and in vivo synergistic activity of arbekacin combinations are necessary to clarify the clinical role of this aminoglycoside.

As per their internal capital adequacy assessment process (ICAAP) and own risk and solvency assessment (ORSA) frameworks, financial institutions (FIs) are subject to both regulatory capital (RC) and economic capital (EC) requirements, the maximum of which becomes the binding constraint, determining the minimum amount of available capital the FI needs to hold. This paper examines alternative strategies and dynamics of the relative RC and EC relationship as FIs seek to maximise return on equity (ROE). The paper shows that EC remains relevant even in cases where RC requirements are higher on aggregate. Under such circumstances FIs are incentivised to 'dial up' economic risk by expanding businesses that consume more EC than RC or by divesting businesses consuming more RC than EC in order to enhance ROE. It is explicitly shown that dialling up economic risk lifts up return on EC, boosting ROE. As these opportunities are arbitraged away, EC and RC requirements will tend to converge over time. These strategies, while improving ROE, come at an economic cost. While improving ROE in the short run, low return on EC business may need to be acquired or high return on EC business may need to be divested. The higher the RC relative to EC on aggregate, the higher the potential economic cost. Both the FIs and regulators should prefer EC being the binding constraint on aggregate, supported by strong ICAAP and ORSA frameworks. [ABSTRACT FROM AUTHOR]

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This paper proposes an efficient matching algorithm based on ASIFT (Affine Scale-Invariant Feature Transform) which is fully invariant to affine transformation. In our approach, we proposed a method of reducing similar measure matching cost and the number of outliers. First, we combined the Manhattan and Chessboard metrics replacing the Euclidean metric by a linear combination for measuring the similarity of keypoints. These two metrics are simple but really efficient. Using our method the computation time for matching step was saved and also the number of correct matches was increased. By applying an Optimized Random Sampling Algorithm (ORSA), we can remove most of the outlier matches to make the result meaningful. This method was experimented on various combinations of affine transform. The experimental result shows that our method is superior to SIFT and ASIFT. [ABSTRACT FROM AUTHOR]

We apply a simple model to project the Solvency Capital Requirement (SCR) over several years, using an Own Risk Solvency Assessment (ORSA) perspective, in order to assess the probability of achieving a solvency coverage ratio. To do so, we rely on a simplified framework proposed in Guibert (Bulletin Français d'Actuariat 10(20), ) which provides a detailed explanation of the SCR. Then, we take into account temporal dynamics for liabilities, premiums and asset returns. Here, we consider guarantees in non-life insurance. This context, when simplified, allows us to use a lognormal distribution to approximate the distribution of the liabilities. It leads to a simple and tractable model for measuring the uncertainty of the solvency ratio in an ORSA perspective. [ABSTRACT FROM AUTHOR]

The decrease in susceptibility to glycopeptides by oxacillin resistant Staphylococcus aureus (ORSA) has become a current problem. Objective: To evaluate susceptibility to glycopeptides in ORSA strains isolated in the University Hospital, Maracaibo, during the first quarter of 2010. Methods: Oxacillin resistance of the ORSA strains was verified by diffusion on agar (oxacillin 1 µg and cefoxitin 30 µg, OXOID®), a screening test in Müeller Hinton agar with 6 µg/mL of vancomycin (Sigma®), and E-test® for minimum inhibitory concentration (MIC) for oxacillin, detection of PBP2a (Latex, OXOID®) and the mecA gene by polymerase chain reaction (PCR). In addition, susceptibility to glycopeptides was determined by disk diffusion (teicoplanin, 30 µg OXOID®), MIC by E-test®, screening test in Müeller-Hinton agar with teicoplanin (5 µg/ml) or in brain heart infusion agar with vancomycin (6 µg/mL), glycopeptide hetero-resistance detection by GDR E-test® and detection of the vanA gene using PCR. Results: No ORSA strain was isolated with intermediate resistance (VISA or hVISA), nor with high-level resistance to glycopeptides. Conclusions: Locally, there is no incidence of ORSA strains resistant to glycopeptides; therefore, these antibiotics continue to be useful for treating infections produced by this important pathogen. [ABSTRACT FROM AUTHOR]

Background: Vancomycin is the treatment of choice for oxacillin-resistant Staphylococcus aureus (ORSA) infections in long bones. However, an inappropriate dosage of vancomycin may result in toxicity or treatment failure. Materials and methods: In this study, 21 patients infected with ORSA were treated with intravenous vancomycin. The concentration of serum vancomycin was measured by fluorescence polarization immunoassay. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were also measured at each blood sampling. Results: When vancomycin doses were given based on the manufacturer's recommendations, 46% (39/84) of the patients were found to have inappropriate blood levels. After the dose of vancomycin was then adjusted, at the third blood sampling, a higher percentage of adequate peak and trough serum vancomycin concentrations were found. There was no statistical difference in peak or trough levels produced by intravenous doses of vancomycin of 500 mg given every 6 h or 1,000 mg given every 12 h. However, initial dosing of 1,000 mg every 12 h may be a better choice than 500 mg every 6 h for younger patients. The CRP was significantly decreased ( P < 0.01) at the time of the second blood sampling during vancomycin treatment. Conclusions: The data from this study suggest that peak and trough vancomycin concentrations should be monitored for patients who have chronic osteomyelitis and prolonged vancomycin treatment. Further studies may help resolve whether such monitoring beneficially affects outcomes and health care costs. [ABSTRACT FROM AUTHOR]

Introduction: Methicillin resistant Staphylococcus aureus has emerged as an important pathogen in nosocomial and community acquired infections. Accurate and rapid identification of MRSA in clinical specimens is essential for timely decision of effective antimicrobial chemotherapy. Aim: The present study was conducted to compare efficacy of four conventional phenotypic methods, with mec- A based polymerase chain reaction (PCR) for MRSA identification. materials and methods: Methicillin resistance was determined in 200 S.aureus isolates by oxacillin disc diffusion, cefoxitin disc diffusion, Oxacillin Resistance Screening Agar and E-test. The results were compared with mec-A based PCR. Results: Among 200 S.aureus isolates 62 (31%) were positive for mec-A gene by PCR. Cefoxitin disc diffusion, Oxacillin Resistance Screening Agar and E-test showed 100% specificity. Oxacillin disc diffusion had lowest sensitivity (82.5%) and specificity (98.5%) among all. The conventional methods take more time than PCR for diagnosing MRSA. Linezolid, Vancomycin & Dalfopristin were the highly sensitive drugs against MRSA isolates. Conclusion: Cefoxitin disc diffusion, is rapid, simple and cheaper, hence can be used routinely as an alternative to PCR for detection of MRSA in resource constraint laboratories. [ABSTRACT FROM AUTHOR]

In the last decades, increasing numbers of patients with problematic bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) have been reported. Beside the common problem of MRSA variants in hospitals, recently community-based MRSA (cMRSA) has become a growing problem even in patients without typical risk factors. cMRSA often carries the virulence factor Panton-Valentine-leukocidin (PVL) causing dermatologic diseases like therapy-refractory furunculosis in young adults. Thus, it is both a medical and health economic issue to identify MRSA as quickly as possible and then eradiate it completely. We review the practical consequences and in particular, the therapy options which are reasonable once MRSA is identified. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to characterize oxacillin-resistant Staphylococcus aureus (ORSA) isolates from livestock environments and meat market workers by molecular epidemiological analysis. Staphylococcal enterotoxin reversed passive latex agglutination (RPLA) and multiplex polymerase chain reactions (PCR) were used to detect enterotoxin-producing S. aureus. The molecular genetic similarity of ORSA was also compared by pulse-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). A total of 30 ORSA isolates were identified and 27 of these strains were from human sources—a higher contamination potential from human origin in the animal raising and handling field was suspected. The most common type of enterotoxin detected in this study was type B. Regarding the bacterial phylogenetic analysis of ORSA isolates, five major clusters of PFGE patterns were suggested with >80% similarity in cluster I. Seven MLST patterns were identified with the most prevalent types being ST338/ST338slv and ST59. Population genetic studies based on MLST have shown that major ORSA clones have emerged from six clonal complexes (CCs), with CC59 being the dominant one. In conclusion, a high prevalence of ORSA with enterotoxin type B as well as ST59 and ST338/ST338slv colonization was observed among livestock with human origins in this study. We suggest further tracking and comparing of the epidemiological evidence of community-acquired and hospital-acquired ORSA in human living environments and livestock-producing environments. [Copyright &y& Elsevier]

Copyright of Der Hautarzt is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)