The generally accepted definition of ecthyma gangrenosum (EG) states that this condition is pathognomonic of Pseudomonas septicemia (Pseudomonas aeruginosa) and that it should usually be seen in immunocompromised patients, particularly those with underlying malignant disease. The cases described in the literature present a somewhat different picture. Our objective was to analyze this controversy. The review analyzes 167 cases of EG that were described in the literature from 1975 to 2014. All articles on EG cases with EG-specific tissue defect that had signs of general and/or local infection and skin necrosis were included and analyzed, whatever the etiology detected. Necrotic lesions of the skin diagnosed as EG have various microbiological etiology, can occur in immunocompetent or even healthy persons, and are not necessarily connected with septicemia. In published cases, P. aeruginosa was detected in 123 cases (73.65%); of them, there were only 72 cases (58.5%) with sepsis. Other bacterial etiology was detected in 29 cases (17.35%) and fungi were detected in 15 cases (9%). While the clinical picture of the disease and the treatment strategy remain the same, there is no need to invent two separate definitions for Pseudomonas and non-Pseudomonas cases. We suggest accepting a broader definition of EG.

Sequence-based typing (SBT) for Legionella pneumophila (Lp) has dramatically improved Legionnaires' disease (LD) cluster investigation. Microbial whole genome sequencing (WGS) is a promising modality for investigation but sequence analysis methods are neither standardised, nor agreed. We sought to develop a WGS-based typing scheme for Lp using de novo assembly and a genome-wide gene-by-gene approach (core genome multilocus sequence typing, cgMLST). We analysed 17 publicly available Lp genomes covering the whole species variation to define a core genome (1,521 gene targets) which was validated using 21 additional published genomes. The genomes of 12 Lp strains implicated in three independent cases of paediatric humidifier-associated LD were subject to cgMLST together with three 'outgroup' strains. cgMLST was able to resolve clustered strains and clearly identify related and unrelated strains. Thus, a cgMLST scheme was readily achievable and provided highresolution analysis of Lp strains. cgMLST appears to have satisfactory discriminatory power for LD cluster analysis and is advantageous over mapping followed by single nucleotide polymorphism (SNP) calling as it is portable and easier to standardise. cgMLST thus has the potential for becoming a gold standard tool for LD investigation. Humidifiers pose an ongoing risk as vehicles for LD and should be considered in cluster investigation and control efforts.

Swab cultures are valuable in identifying pathogens in diabetic foot wounds when bone is not involved. When surgical debridement is contraindicated or delayed, swab cultures can be used to select appropriate antibiotic therapy.

Extended-spectrum ␤-lactamase (ESBL)-producing Enterobacteriaceae are pathogens that may lead to a spectrum of clinical syndromes. We aimed to identify predictors and outcomes of ESBL bacteremia upon hospital admission (UHA) in a nationwide prospective study. Thus, a multicenter prospective study was conducted in 10 Israeli hospitals. Adult patients with bacteremia due to Enterobacteriaceae diagnosed within 72 h of hospitalization were included. Patients with ESBL producers (cases) were compared to those with non-ESBL producers (controls), and a 1:1 ratio was attempted in each center. A case-control study to identify predictors and a cohort study to identify outcomes were conducted. Bivariate and multivariate logistic regressions were used for analyses. Overall, 447 patients with bacteremia due to Enterobacteriaceae were recruited: 205 cases and 242 controls. Independent predictors of ESBL were increased age, multiple comorbid conditions, poor functional status, recent contact with health care settings, invasive procedures, and prior receipt of antimicrobial therapy. In addition, patients presenting with septic shock and/or multiorgan failure were more likely to have ESBL infections. Patients with ESBL producers suffered more frequently from a delay in appropriate antimicrobial therapy (odds ratio [OR], 4.7; P, <0.001) and had a higher mortality rate (OR, 3.5; P, <0.001). After controlling for confounding variables, both ESBL production (OR, 2.3; P, 9.1) and a delay in adequate therapy (OR, 0.05; P, 0.001) were significant predictors for mortality and other adverse outcomes. We conclude that among patients with bacteremia due to Enterobacteriaceae UHA, those with ESBL producers tend to be older and chronically ill and to have a delay in effective therapy and severe adverse outcomes. Efforts should be directed to improving the detection of patients with ESBL bacteremia UHA and to providing immediate appropriate therapy.Enterobacteriaceae producing extended-spectrum ␤-lactameses (ESBL) pose a major worldwide threat (27). These pathogens are resistant to all penicillins and cephalosporins and often are coresistant to multiple other classes of antibiotics (2). Thus, therapeutic options to treat infections with these pathogens are limited (27). The Infectious Diseases Society of America has listed ESBL-producing Enterobacteriaceae as pathogens necessitating the urgent development of new and novel therapeutics (37). While infections caused by ESBLproducing strains have been acquired primarily in hospitals and health care institutions, recent reports from multiple parts of the world show that these pathogens now have a role in community-acquired infections as well (2,3,5,6,8,9,12,15,19,27,29,30,32,38). The burden of these infections is enormous, and compared to bacteremia caused by non-ESBL-producing Enterobacteriaceae, infections caused by ESBL producers are associated with a significantly higher mortality rate, 6 additional days of hospitalization, and approximately $10,000 in additional costs per case (35,36).There ...

A recent, frequently quoted study has suggested that for bloodstream infections (BSIs) due to extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL) Escherichia coli, treatment with β-lactam/β-lactamase inhibitors (BLBLIs) might be equivalent to treatment with carbapenems. However, the majority of BSIs originate from the urinary tract. A multicenter, multinational efficacy analysis was conducted from 2010 to 2012 to compare outcomes of patients with non-urinary ESBL BSIs who received a carbapenem (69 patients) vs those treated with piperacillin-tazobactam (10 patients). In multivariate analysis, therapy with piperacillin-tazobactam was associated with increased 90-day mortality (adjusted odds ratio, 7.9, P=.03). For ESBL BSIs of a non-urinary origin, carbapenems should be considered a superior treatment to BLBLIs.

S. bovis bacteremia is a serious disease that affects elderly immunosuppressed individuals. Infection is strongly associated with colon pathology and endocarditis, regardless of the new taxonomy or clone complex. The identification of S. bovis is of paramount importance, and microbiology laboratories should differentiate its processing from that of other S. viridans.

Respiratory infections (RI) can be viral or bacterial in origin. In either case, the invasion of the pathogen results in production and release of various volatile organic compounds (VOCs). The present study examines the VOCs released from cultures of five viruses (influenza A, influenza B, adenovirus, respiratory syncitial virus and parainfluenza 1 virus), three bacteria (Moraxella catarrhalis, Haemophilus influenzae and Legionella pneumophila) and Mycoplasma pneumoniae isolated colonies. Our results demonstrate the involvement of inflammation-induced VOCs. Two significant VOCs were identified as associated with infectious bacterial activity, heptane and methylcyclohexane. These two VOCs have been linked in previous studies to oxidative stress effects. In order to distinguish between bacterial and viral positive cultures, we performed principal component analysis including peak identity (retention time) and VOC concentration (i.e. area under the peak) revealing 1-hexanol and 1-heptadecene to be good predictors.

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