Enterococcal bloodstream infection. Design and validation of a mortality prediction rule.

BACKGROUND: To develop a prediction rule to describe the risk of death as a result of enterococcal bloodstream infection. METHODS: A prediction rule was developed by analysing data collected from 122 patients diagnosed with enterococcal BSI admitted to the Clínica Universidad de Navarra (Pamplona, Spain); and validated by confirming its accuracy with the data of an external population (Hospital del Mar, Barcelona). RESULTS: According to this model, independent significant predictors for the risk of death were being diabetic, have received appropriate treatment, severe prognosis of the underlying diseases, have renal failure, received solid organ transplant, malignancy, source of the bloodstream infection and be immunosuppressed. The prediction rule showed a very good calibration (Hosmer-Lemeshow statistic, P = 0.93) and discrimination for both training and testing sets (area under ROC curve = 0.84 and 0.83 respectively). CONCLUSIONS: The predictive rule was able to predict risk of death as a result of enterococcal bloodstream infection as well as to identify patients, who being below the threshold value, will have a low risk of death with a negative predictive value of 96%.

[Mortality risk factors for bloodstream infections caused by extended-spectrum beta-lactamase-producing microorganisms]. / Factores de riesgo de mortalidad en pacientes con bacteriemia por cepas productoras de betalactamasas de espectro extendido.

OBJECTIVE: To identify risk factors for mortality in patients with bloodstream infection by extended-spectrum beta-lactamase (ESBL)-producing microorganisms. MATERIAL AND METHODS: A retrospective study in patients with bloodstream infection by ESBL-producing microorganisms from January 2000 to December 2006 was carried out. RESULTS: A total of 4,172 bloodstream infections were identified, 1,218 (29.2%) and 226 (5.4%) of which were caused by Escherichia coli and Klebsiella pneumoniae, respectively. The overall mortality rate was 50.9% in patients with bacteriema due to ESBL-producing strains. The binomial logistic regression model, adjusted for age and severity, identified admission to an intensive care unit (OR 38,631; 95%CI:3,375-424,618; P=.002) and a SAPS II severity index score >30 in the 24-48 h before obtaining blood culture (OR 17,980; 95% CI:2,193-170,439; P=.010) as factors associated to mortality, while the urinary tract as primary site of infection was an independent determinant for non-mortality (OR 0.184; 95% CI:0.034-0.975; P=.047). CONCLUSIONS: Patients with suspicion of bacteriema who have been admitted to the ICU with a score of elevated severity should be candidates for early empirical treatments as they have a greater risk of mortality. However, the benefit of this strategy may be limited due to the baseline severity of the patient.

Factores de riesgo de mortalidad en pacientes con bacteriemia por cepas productoras de betalactamasas de espectro extendido / Mortality risk factors for bloodstream infections caused by extended-spectrum beta-lactamase-producing microorganisms

Objetivo. Identificar los factores de riesgo de mortalidad en pacientes con bacteriemia por microorganismos productores de betalactamasas de espectro extendido (BLEE). Material y métodos. Estudio retrospectivo de cohortes en pacientes con bacteriemia por microorganismos productores de BLEE desde enero de 2000 hasta diciembre de 2006. Resultados. Se identificaron 4.172 episodios de bacteriemia. De ellos, 1.218 (29,2%) fueron causados por Escherichia coli y 226 (5,4%) por Klebsiella pneumoniae, de los que en 42 y en 11 se aislaron cepas productoras de BLEE, respectivamente. La mortalidad cruda fue del 50,9% en los pacientes que presentaron bacteriemia por cepas productoras de BLEE. El modelo de regresión logística binomial, ajustado por edad y gravedad, identificó el ingreso en una unidad de cuidados intensivos (UCI) (odds ratio: 38,631; intervalo de confianza [IC] del 95%, 3,375-424,618; p=0,002) y un valor del índice de gravedad SAPS II superior a 30 en las 24-48h previas a la extracción de la muestra para hemocultivo que posteriormente resultó positivo (OR: 17,980; IC del 95%, 2,193-170,439; p=0,010) como factores asociados a mortalidad, mientras que el presentar bacteriemia de foco urinario resultó un factor protector (OR: 0,184; IC del 95%, 0,034-0,975; p=0,047). Conclusiones. Los pacientes con sospecha de bacteriemia y que hayan presentado un ingreso en la UCI y una puntuación de gravedad elevada deberían ser candidatos a recibir tratamiento empírico precoz al presentar un mayor riesgo de mortalidad. No obstante, el beneficio de esta estrategia puede verse limitado por la gravedad basal del paciente(AU)

Objective. To identify risk factors for mortality in patients with bloodstream infection by extended-spectrum beta-lactamase (ESBL)-producing microorganisms. Material and methods. A retrospective study in patients with bloodstream infection by ESBL-producing microorganisms from January 2000 to December 2006 was carried out. Results. A total of 4,172 bloodstream infections were identified, 1,218 (29.2%) and 226 (5.4%) of which were caused by Escherichia coli and Klebsiella pneumoniae, respectively. The overall mortality rate was 50.9% in patients with bacteriema due to ESBL-producing strains. The binomial logistic regression model, adjusted for age and severity, identified admission to an intensive care unit (OR 38,631; 95%CI:3,375-424,618; P=.002) and a SAPS II severity index score >30 in the 24-48h before obtaining blood culture (OR 17,980; 95% CI:2,193-170,439; P=.010) as factors associated to mortality, while the urinary tract as primary site of infection was an independent determinant for non-mortality (OR 0.184; 95% CI:0.034-0.975; P=.047). Conclusions. Patients with suspicion of bacteriema who have been admitted to the ICU with a score of elevated severity should be candidates for early empirical treatments as they have a greater risk of mortality. However, the benefit of this strategy may be limited due to the baseline severity of the patient(AU)

Clinical characteristics and outcomes of patients with vancomycin-susceptible Enterococcus faecalis and Enterococcus faecium bacteraemia in cancer patients.

The purpose of this investigation was to compare the risk factors, clinical features and outcomes in cancer patients with bacteraemia caused by vancomycin-susceptible Enterococcus faecalis and E. faecium. A retrospective, observational 7-year study was carried out in a 450-bed, acute-care university-affiliated hospital. We performed univariate comparisons between the two groups and then multivariate analysis to identify patient risk factors for E. faecium isolation. Seventy-three patients were included in the analysis: 54 (74.0%) with bacteraemia caused by E. faecalis and 19 (26.0%) by E. faecium. The Simplified Acute Physiological Score (SAPS) value was significantly greater in E. faecium isolates (40.7 vs. 35.2; p = 0.009). Diabetes mellitus was more frequently diagnosed in patients with E. faecium bacteraemia (52.6% vs. 24.1%; p = 0.021). Prior penicillin exposure was more frequent in patients with E. faecium bacteraemia (68.4% vs. 29.6%; p = 0.003). There was a trend toward higher mortality in E. faecium bacteraemia patients (47.4% vs. 25.9%; p = 0.084). Independent patient risk factors for E. faecium isolation were prior penicillin exposure (odds ratio [OR], 6.479; p = 0.003) and SAPS > 34 (OR, 6.896; p = 0.009). When compared to E. faecalis bacteraemia, E. faecium bacteraemia in cancer patients is independently associated with more severe illness and prior use of penicillins; therefore, empiric treatment which would cover E. faecium should be considered in cancer patients suspected of having bacteraemia.

Acoustic barriers obtained from industrial wastes.

Acoustic pollution is an environmental problem that is becoming increasingly more important in our society. Likewise, the accumulation of generated waste and the need for waste management are also becoming more and more pressing. In this study we describe a new material--called PROUSO--obtained from industrial wastes. PROUSO has a variety of commercial and engineering, as well as building, applications. The main raw materials used for this environmentally friendly material come from slag from the aluminium recycling process, dust from the marble industry, foundry sands, and recycled expanded polystyrene from recycled packaging. Some natural materials, such as plastic clays, are also used. To obtain PROUSO we used a conventional ceramic process, forming new mineral phases and incorporating polluted elements into the structure. Its physical properties make PROUSO an excellent acoustic and thermal insulation material. It absorbs 95% of the sound in the frequency band of the 500 Hz. Its compressive strength makes it ideal for use in ceramic wall building.

Heavy metal-rich wastes sequester in mineral phases through a glass-ceramic process.

Certain sludges generated by industry are rich in contaminating elements and are a major environmental problem. In this study, we determine the ability of these contaminating elements to be incorporated into a glass-matrix and in various mineral phases after a crystallization process. The contaminating elements studied were obtained from sewage sludges (SS) and galvanic sludges (GS), our raw materials. The sludge samples were taken from urban wastewater treatment plant in Catalonia (NE Spain) with high levels of phosphorus oxide (P(2)O(5)). In silica glasses, P(2)O(5) acts as a network former. We determined the chemical composition of both the SS and GS, as well as their thermal behaviour by differential thermal analysis and thermal gravimetric analysis (DTA-TG) to obtain their melting curves. The vitreous transition temperature of the obtained glass was established by dilatometer technique at 725 degrees C. The DTA-TG curve of the glass obtained has an exothermal wide peak at 860 degrees C corresponding to crystallization of the two phases: a spinel phase and a phosphate phase. A second exothermal wide peak at 960 degrees C was attributed to the crystallization of aluminium pyroxene, anorthite and fluor-apatite, with two exothermal phenomena attributed to the evolution of these phases. An exothermal peak at 1100 degrees C was attributed to gehlenite crystallization. Scanning electron microscope observations and energy-dispersed X-ray spectroscopy microanalyses of glass-ceramic showed that the contaminating elements were concentrated in the spinel phases, which are the first phases to crystallize during the cooling of glass. Finally, the spinel structure permits the incorporation of all the contaminating elements into it.

Evaluation by Vickers indentation of fracture toughness of a phosphate biodegradable glass.

Indentation tests are commonly used for the evaluation of fracture toughness of brittle materials, particularly glasses and ceramics, because this technique requires only a small polished area on the specimen surface from which a large number of data points can be generated rapidly. However, a wide variety of equations for the calculation of fracture toughness of ceramic materials by means of Vickers indentation are available. Such equations are obtained phenomenologically and their parameters adjusted in such a way that the KIC values obtained are in good agreement with those obtained by conventional methods. This is the reason why it is necessary to check which type of equation reproduces more accurately the results obtained by means of conventional methods for the material which is going to be investigated. In the present work seven different fracture toughness equations widely used in glass and ceramic studies are considered and the results are compared with those obtained by conventional methods, such as single-edge notch beam (SENB) specimens tested in three-point bending. The role played by the applied indentation load is considered.