[Rapid antibiotic susceptibility test in Clinical Microbiology]. / Antibiograma rápido en Microbiología Clínica.

The most widely used antibiotic susceptibility testing methods in Clinical Microbiology are based on the phenotypic detection of antibiotic resistance by measuring bacterial growth in the presence of the antibiotic being tested. These conventional methods take typically 24hours to obtain results. A review is presented here of recently developed techniques for the rapid determination of antibiotic susceptibility. Data obtained with different methods such as molecular techniques, flow cytometry, chemiluminescence, mass spectrometry, commercial methods used in routine work, colorimetric methods, nephelometry, microarrays, microfluids, and methods based on cell disruption and sequencing, are analyzed and discussed in detail.

A two-hour antibiotic susceptibility test by ATP-bioluminescence.

The antibiotic susceptibility test (AST) in Clinical Microbiology laboratories is still time-consuming, and most procedures take 24h to yield results. In this study, a rapid antimicrobial susceptibility test using ATP-bioluminescence has been developed. The design of method was performed using five ATCC collection strains of known susceptibility. This procedure was then validated against standard commercial methods on 10 strains of enterococci, 10 staphylococci, 10 non-fermenting gram negative bacilli, and 13 Enterobacteriaceae from patients. The agreement obtained in the sensitivity between the ATP-bioluminescence method and commercial methods (E-test, MicroScan and VITEK2) was 100%. In summary, the preliminary results obtained in this work show that the ATP-bioluminescence method could provide a fast and reliable AST in two hours.

New procedure for rapid identification of microorganisms causing urinary tract infection from urine samples by mass spectrometry (MALDI-TOF).

INTRODUCTION: Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry is widely established as a technique in clinical microbiology laboratories for the identification of microorganisms. Using this technique, it is also possible to obtain the identification of microorganisms from untreated urine samples. METHODS: In this study, a differential centrifugation protocol and a criterion for validation of the results in order to achieve microbial identification from untreated urine samples are proposed. Additionally, the sensitivity of the analytical procedure in monobacterial urine samples has been evaluated. RESULTS: A 90% sensitivity (confidence interval of 81.96%-94.84%) was obtained in urine samples with bacterial counts of ≥1×10(5)CFU/ml, and it was possible to improve the percentages of direct identifications from urine samples with bacterial counts of <1×10(5)CFU/ml. CONCLUSION: It is concluded that the MALDI-TOF system is both fast and reliable in the identification of individual microorganisms from untreated urine samples with counts of ≥1×10(5)CFU/ml.

[In vitro activity of ceftaroline against Spanish isolates of Staphylococcus aureus: a multicenter study]. / Estudio multicéntrico sobre la actividad in vitro de ceftarolina frente a Staphylococcus aureus aislados en España.

INTRODUCTION: Ceftaroline fosamil is a new-generation antimicrobial agent of cephalosporins subgroup. It is the first commercially available beta-lactam antibiotic that exhibits activity against methicillin-resistant Staphylococcus aureus (MRSA). The aim of this study is to determine the in vitro Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values of ceftaroline against S.aureus strains (including MRSA). MATERIAL AND METHODS: A multicenter study involving four hospitals representative of the Spanish geography was performed. MIC and MBC values against both the methicillin-resistant and sensitive strains of S.aureus (MRSA and methicillin-sensitive S.aureus [MSSA]) were determined using a broth microdilution method. RESULTS: A total of 266 S.aureus strains were analyzed (95 MRSA and 171 MSSA). Ceftaroline bacterial sensitivity showed a mean MIC of 0.227 µg/ml (SD=0.146; range, 0.06 to 1 µg/ml). All MIC values of the 266 strains tested belonged to the sensitive category (value ≤ 1 µg/ml). Intermediate or resistant strains were not detected. MIC50 and MIC90 values for MRSA were 0.25 and 0.5 µg/ml, respectively (range=0.125-1 µg/ml). MSSA strains showed MIC50 and MIC90 values of 0.125 and 0.25 µg/ml, respectively (range=0.125-0.5 µg/ml). MBC50 and MBC90 values for MRSA were 0.5 and 1 µg/ml, respectively (range=0.125-1 µg/ml). MSSA strains showed MBC50 and MBC90 values of 0.25 and 0.25 µg/ml, respectively (range=0.125-0.5 µg/ml). CONCLUSION: Ceftaroline shows excellent in vitro activity against S.aureus, including MRSA strains. Therefore, this antibiotic may be a promising alternative for the treatment of infections caused by this bacterium.

A two-hour procedure for determining the susceptibility of enterococci and staphylococci to antibiotics by a colourimetric method.

INTRODUCTION: Rapid determination of the antibiotic susceptibility test in bacteria remains a challenge for Clinical Microbiology laboratories. METHODS: An improvement in the colorimetric antimicrobial susceptibility testing performed with resazurin in enterococci and staphylococci has been carried out. The design of method was performed using two collection strains, which have a known susceptibility. This procedure was then validated against standard commercial methods on 15 strains of staphylococci and 15 strains of enterococci from patients. RESULTS: The essential agreement between the colorimetric method and commercial methods (E-test, MicroScan and VITEK2) was 100%. CONCLUSION: Resazurin allows us to obtain a reliable antibiotic susceptibility test in staphylococci and enterococci in less than two hours.

Susceptibility of the Acinetobacter calcoaceticus-A. baumannii complex to imipenem, meropenem, sulbactam and colistin.

The Acinetobacter calcoaceticus-Acinetobacter baumannii complex includes some of the most clinically relevant species of the genus Acinetobacter due to their capacity to cause epidemic nosocomial outbreaks as well as their increasing resistance to antibiotics. Susceptibility of Acinetobacter strains varies greatly depending on origin, thus highlighting the importance of local analyses of susceptibility profiles. Two hundred twenty-one strains of the A. calcoaceticus-A. baumannii complex were identified using biochemical tests and were biotyped. Strain susceptibility to imipenem, meropenem, colistin and sulbactam was studied using agar dilution. Eight different biotypes were found, type 1 accounting for 69.2% of the strains. MIC(50) and MIC(90) to imipenem, meropenem, colistin and sulbactam were 4 and 8 mg/l, 16 and 32 mg/l, 0.5 and 1mg/l, and 8 and 16 mg/l, with susceptibility rates of 64.3, 22.6, 98.2 and 73.8%, respectively. Biotype 1 was the most resistant. A statistically significant difference was observed for the mean MIC of the four predominant biotypes to imipenem, meropenem and sulbactam but not to colistin.

Thermotherapy in calcaneal infection due to Prototheca wickerhamii / Termoterapia en infección calcánea debida a Prototheca wickerhamii

No disponible

Bacteremia due to Cellulosimicrobium cellulans associated with central catheter for hemodialysis / Bacteriemia asociada a catéter central para hemodiálisis debida a Cellulosimicrobium cellulans

No disponible

Aortic valve-derived calcifyng nanoparticles: no evidence of life.

INTRODUCTION AND OBJECTIVES: Calcifying nanoparticles, also known as "nanobacteria," are very small bacteria-like structures (0.1-0.5 µm) with the ability to facilitate the precipitation and growth of calcium phosphate in pathological conditions and have been associated with aortic valve calcification. The status of nanobacteria is controversial; some have proposed that they are a new class of living organism while others describe calcifying nanoparticles as mineralo-fetuin complexes. The objective of the present study is to elucidate if calcifying nanoparticles are living entities, based on whether or not they have metabolic activity, a characteristic of life, irrespective of their composition. METHODS: Calcifying nanoparticles were grown from 6 different valves randomly chosen among 84 consecutively explanted aortic valves, as described in the literature. The (1)H-NMR spectra were acquired from calcifying nanoparticles culture media to assess metabolic changes and the presence of 16sRNA in the culture media was investigated by real-time polymerase chain reaction. RESULTS: After 6 weeks in culture, calcifying nanoparticles could be seen clearly attached to the surface of culture flasks. All samples were negative for 16sRNA, discarding the presence of known bacteria. (1)H-NMR spectra showed no difference between calcifying nanoparticles and 6-week-old sterile culture media maintained under the same conditions. CONCLUSIONS: Our results show that calcifying nanoparticles cannot be considered as living organisms.

Antibiograma rápido en Microbiología Clínica / Rapid antibiotic susceptibility test in Clinical Microbiology

Los métodos más frecuentemente utilizados en Microbiología Clínica para la determinación de la sensibilidad de las bacterias a los antibióticos se basan en un estudio fenotípico, observando el crecimiento bacteriano de la cepa incubada en presencia del antibiótico a estudiar. Estos métodos requieren normalmente un tiempo de unas 24 h para la obtención de resultados. El objetivo de este trabajo es revisar el fundamento y los resultados de las principales técnicas instrumentales que proporcionan un antibiograma rápido. De manera pormenorizada se exponen datos relativos a técnicas moleculares, citometría de flujo, quimioluminiscencia, espectrometría de masas, métodos comerciales utilizados en el trabajo de rutina, métodos colorimétricos, nefelometría, microarrays, microfluidos y métodos de lisis bacteriana

The most widely used antibiotic susceptibility testing methods in Clinical Microbiology are based on the phenotypic detection of antibiotic resistance by measuring bacterial growth in the presence of the antibiotic being tested. These conventional methods take typically 24 hours to obtain results. A review is presented here of recently developed techniques for the rapid determination of antibiotic susceptibility. Data obtained with different methods such as molecular techniques, flow cytometry, chemiluminescence, mass spectrometry, commercial methods used in routine work, colorimetric methods, nephelometry, microarrays, microfluids, and methods based on cell disruption and sequencing, are analyzed and discussed in detail

Evaluación del analizador de orinas Sysmex UF-1000i como método de cribado en el diagnóstico de la infección del tracto urinario / Evaluation of urine analyzer Sysmex UF-1000i as a screening method in the diagnosis of urinary tract infection

Introducción. Las muestras de orina son las más frecuentemente procesadas en los laboratorios de microbiología clínica. Teniendo en cuenta que del 60 al 80% de las muestras proporcionan resultados negativos, es recomendable realizar un cribado de las orinas para disminuir los gastos y la carga de trabajo, y adelantar los resultados negativos. El objetivo del trabajo fue evaluar el rendimiento del recuento de leucocitos y de bacterias en el analizador Sysmex UF-1000i para discriminar qué muestras debían ser procesadas para el cultivo convencional. Material y métodos. Mediante el procesamiento de una muestra representativa de la población de 922 muestras de orina, se calcularon, mediante curvas ROC, los puntos de corte óptimos de recuento bacteriano y de recuento de leucocitos con la finalidad de obtener la mejor sensibilidad para la mayor especificidad y, utilizando estos valores, se calcularon las características operacionales del cribado. Los cálculos estadísticos fueron realizados mediante los programas Analyze-it v.2.11 para Microsoft Excel y SPSS v.20.0. Resultados. La mejor sensibilidad para la mayor especificidad se obtuvo con los puntos de corte de 247.850 bacterias/ml o 31.800 leucocitos/ml. Utilizando estos puntos de corte, se obtuvo una sensibilidad del 90,6% (IC 95%: 86,7-94,6), una especificidad del 66,3% (IC 95%: 62,9-69,9), un valor predictivo de la prueba positiva del 47,8% (43,0%-52,1%) y un valor predictivo de la prueba negativa del 95,4% (IC 95%: 93,4-97,4). Conclusión. El Sysmex UF-1000i muestra unas características operacionales adecuadas para su incorporación en los laboratorios de microbiología clínica (AU)

Introduction. Urine samples are those most commonly processed in clinical microbiology laboratories. Given that around 60-80% of samples are negative, a screening urine samples is recommended for reducing costs of and technical staff workload, and for anticipating negative results. The aim of the work was to evaluate the Sysmex UF-1000i performance obtained from bacterial counts and leukocyte counts in order to discriminate samples must be cultured. Material and methods. By processing a representative sample of the population of 922 urines samples, an optimization of the screening was performed through calculating the optimal thresholds of the equipment through ROC curves in order to obtain the best sensitivity for the best specificity. Using these values, the operational characteristics of the screening were calculated. Statistical calculations were performed using the softwares Analyze-it v.2.11 for Microsoft Excel and SPSS v.20.0. Results. The best sensitivity for the best specificity was obtained with the cut-offs 247,850 bacteria/mL and 31,800 leukocytes/mL. By using these cutoffs, a 90,6% sensitivity (95% CI: 86.7-94.6), 66.3% specificity (95% CI: 62.9-69.9), 47.8% positive predictive value (95% CI: 43.0-52.1) and 95.4% negative predictive value (95% CI: 93.4-97.4) were obtained. Conclusion. The Sysmex UF-1000i shows suitable operational characteristics for its incorporation into clinical microbiology laboratories (AU)

A two-hour antibiotic susceptibility test by ATP-bioluminescence / Antibiograma en dos horas mediante la medición de ATP por bioluminiscencia

The antibiotic susceptibility test (AST) in Clinical Microbiology laboratories is still time-consuming, and most procedures take 24 h to yield results. In this study, a rapid antimicrobial susceptibility test using ATP-bioluminescence has been developed. The design of method was performed using five ATCC collection strains of known susceptibility. This procedure was then validated against standard commercial methods on 10 strains of enterococci, 10 staphylococci, 10 non-fermenting gram negative bacilli, and 13 Enterobacteriaceae from patients. The agreement obtained in the sensitivity between the ATP-bioluminescence method and commercial methods (E-test, MicroScan and VITEK2) was 100%. In summary, the preliminary results obtained in this work show that the ATP-bioluminescence method could provide a fast and reliable AST in two hours

La mayoría de procedimientos diagnósticos para el estudio de la sensibilidad de las bacterias a los antibióticos en Microbiología Clínica requieren unas 24 horas para la obtención de resultados. En este estudio se propone una metodología para llevar a cabo un antibiograma rápido mediante la medición de ATP por bioluminiscencia. El diseño del antibiograma se realizó mediante el uso de cinco cepas de colección ATCC, las cuales presentan una sensibilidad conocida. Este diseño fue posteriormente validado frente a los métodos comerciales de antibiograma mediante el procesamiento de 10 cepas de enterococos, 10 de estafilococos, 10 de bacilos gramnegativos no fermentadores y 13 de Enterobacteriaceae aisladas de pacientes. El acuerdo obtenido entre la sensibilidad obtenida mediante bioluminiscencia y la obtenida mediante los métodos comerciales (E-test, MicroScan and VITEK2) fue del 100%. Por lo tanto, los resultados preliminares obtenidos en este trabajo indican que las medidas de ATP mediante bioluminiscencia podrían proporcionar, en dos horas, un antibiograma rápido y seguro

New procedure for rapid identification of microorganisms causing urinary tract infection from urine samples by mass spectrometry (MALDI-TOF)

INTRODUCTION: Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry is widely established as a technique in clinical microbiology laboratories for the identification of microorganisms. Using this technique, it is also possible to obtain the identification of microorganisms from untreated urine samples. METHODS: In this study, a differential centrifugation protocol and a criterion for validation of the results in order to achieve microbial identification from untreated urine samples are proposed. Additionally, the sensitivity of the analytical procedure in monobacterial urine samples has beenevaluated. RESULTS: A 90% sensitivity (confidence interval of 81.96%-94.84%) was obtained in urine samples with bacterial counts of ≥ 1×105 CFU/ml, and it was possible to improve the percentages of direct identifications from urine samples with bacterial counts of < 1 × 105 CFU/ml. CONCLUSIÓN: It is concluded that the MALDI-TOF system is both fast and reliable in the identification of individual microorganisms from untreated urine samples with counts of ≥ 1 × 105 CFU/mll

INTRODUCCIÓN: El uso de la espectrometría de masas Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) es una técnica implantada en los laboratorios de Microbiología Clínica que permite llevar a cabo la identificación de microorganismos. Una de las aplicaciones de esta técnica es la identificación a partir de muestra directa de orina. MÉTODOS: En este estudio se propone un protocolo de centrifugación diferencial y un criterio de validación de los resultados para alcanzar la identificación microbiana a partir de muestra directa de orina. Adicionalmente se estudia la sensibilidad del procedimiento analítico en muestras de orina monomicrobianas. RESULTADOS: Las orinas con recuentos ≥ 1×105 UFC/ml mostraron un 90% de sensibilidad (Intervalo de Confianza de 81.96%-94.84%) y se logró mejorar los porcentajes de identificación directa a partir de orinas con recuentas bacterianos < 1×105 UFC/ml. CONCLUSIONES: La espectrometría de masas MALDI-TOF es un sistema rápido y fiable para la identificación de microorganismos a partir de orinas monomicrobianas con recuentos ≥ 1 × 105 UFC/ml

A two-hour procedure for determining the susceptibility of enterococci and staphylococci to antibiotics by a colourimetric method / Un procedimiento de dos horas para determinar la sensibilidad de estaficolococos y enterococos a los antibióticos en dos horas mediante un método colorimétrico

Introduction. Rapid determination of the antibiotic susceptibility test in bacteria remains a challenge for Clinical Microbiology laboratories. Methods. An improvement in the colorimetric antimicrobial susceptibility testing performed with resazurin in enterococci and staphylococci has been carried out. The design of method was performed using two collection strains, which have a known susceptibility. This procedure was then validated against standard commercial methods on 15 strains of staphylococci and 15 strains of enterococci from patients. Results. The essential agreement between the colorimetric method and commercial methods (E-test, MicroScan and VITEK2) was 100%. Conclusion. Resazurin allows us to obtain a reliable antibiotic susceptibility test in staphylococci and enterococci in less than two hours (AU)

Introducción. La realización de un antibiograma rápido sigue siendo un reto para los laboratorios de Microbiología Clínica. Métodos. Se ha realizado una mejora en el antibiograma colorimétrico realizado mediante resazurina en estafilococos y enterococos. El diseño del método se realizó mediante el uso de dos cepas de colección que presentan una sensibilidad conocida. Este procedimiento se validó posteriormente frente a los métodos comerciales mediante el procesamiento de 15 cepas de estafilococos y 15 de enterococos aisladas de pacientes. Resultados. Se ha obtenido un 100% de concordancia entre la sensibilidad obtenida mediante resazurina y la obtenida mediante los métodos comerciales (E-test, MicroScan and VITEK2). Conclusión. Mediante el uso de resazurina es posible obtener un antibiograma en estafilococos y enterococos en menos de dos horas de forma fiable (AU)

Estudio multicéntrico sobre la actividad in vitro de ceftarolina frente a Staphylococcus aureus aislados en España / In vitro activity of ceftaroline against Spanish isolates of Staphylococcus aureus: A multicenter study

INTRODUCCIÓN: Ceftarolina fosamil es un nuevo antibiótico de última generación del subgrupo de las cefalosporinas. Es el primer beta-lactámico comercializado que presenta actividad frente a Staphylococcus aureus resistente a la meticilina (SARM). El objetivo del presente estudio es determinar los valores in vitro de la concentración mínima inhibitoria (CMI) y de la concentración mínima bactericida (CMB) de ceftarolina frente a cepas de S. aureus, tanto sensible a la meticilina (SASM) como resistente. MATERIAL Y MÉTODOS: Se realizó un estudio multicéntrico en el que participaron 4 hospitales representativos de la geografía española. Mediante el método de microdilución en caldo se determinaron los valores de CMI y CMB de la ceftarolina frente a cepas de S. aureus (SARM y SASM). RESULTADOS: Se analizaron un total de 266 cepas de S. aureus (95 SARM y 171 SASM). En las 266 cepas analizadas, todos los valores de CMI se encontraron dentro de la categoría de sensible (valor ≤ 1 μg/ml), no detectándose ninguna cepa intermedia ni ni resistente. Las CMI50 y CMI90 para SAMR fueron de 0,25 y 0,5 μg/ml, respectivamente, con un rango de 0,125 a 1 μg/ml. Las CMI50 y CMI90 para SASM fueron de 0,125 y 0,25 μg/ml, con un rango de 0,125 a 0,5 μg/ml. Las CMB50 y CMB90 para SAMR fueron de 0,5 y 1 μg/ml, respectivamente, con un rango de 0,125 a 1 μg/ml. Las CMB50 y CMB90 para SASM fueron de 0,25 y 0,25 μg/ml, con un rango de 0,125 a 0,5 μg/ml. CONCLUSIÓN: Ceftarolina muestra una excelente actividad in vitro frente a S.aureus, incluyendo cepas SARM, por lo que podría presentarse como una alternativa prometedora en el tratamiento de infecciones causadas por esta bacteria

INTRODUCTION: Ceftaroline fosamil is a new-generation antimicrobial agent of cephalosporins subgroup. It is the first commercially available beta-lactam antibiotic that exhibits activity against methicillin-resistantStaphylococcus aureus (MRSA). The aim of this study is to determine the in vitro Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values of ceftar oline against S. aureus strains (including MRSA). MATERIAL AND METHODS: A multicenter study involving four hospitals representative of the Spanish geography was performed. MIC and MBC values against both the methicillin-resistant and sensitive strains of S. aureus (MRSA and methicillin-sensitive S. aureus [MSSA]) were determined using a broth microdilution method. RESULTS: A total of 266 S. aureus strains were analyzed (95 MRSA and 171 MSSA). Ceftaroline bacterial sensitivity showed a mean MIC of 0.227 μg/ml (SD=0.146; range, 0.06 to 1μg/ml). All MIC values of the 266 strains tested belonged to the sensitive category (value ≤1μg/ml). Intermediate or resistant strains were not detected. MIC50 and MIC90 values for MRSA were 0.25 and 0.5μg/ml, respectively (range = 0.125-1 μg/ml). MSSA strains showed MIC50 and MIC90 values of 0.125 and 0.25 μg/ml, respectively (range = 0.125-0.5 μg/ml). MBC50 and MBC90 values for MRSA were 0.5 and 1μg/ml, respectively (range = 0.125-1μg/ml). MSSA strains showed MBC50 and MBC90 values of 0.25 and 0.25 μg/ml, respectively (range = 0.125-0.5 μg/ml). CONCLUSIÓN: Ceftaroline shows excellent in vitro activity against S.aureus, including MRSA strains. Therefore, this antibiotic may be a promising alternative for the treatment of infections caused by this bacterium

Nanopartículas derivadas de válvula aórtica: sin evidencias de vida / Aortic valve-derived calcifyng nanoparticles: no evidence of life

Introducción y objetivos. Las nanopartículas calcificantes, tambien conocidas como nanobacterias, son estructuras, similares a las bacterias, de reducido tamaño (0,1-0,5 μm) que tienen la capacidad de facilitar la precipitación y el crecimiento de fosfato cálcico en condiciones patológicas y a las que se ha asociado con la calcificación de la válvula aórtica. La clasificación de las nanobacterias como organismos no está exenta de controversia; algunos autores apuntan que son una nueva clase de organismo vivo, mientras que otros las describen como complejos mineraloproteicos. El objetivo del trabajo es clarificar si las nanopartículas calcificantes son entes vivos basándonos en si tienen o no actividad metabólica, característica de los seres vivos independiente de su composición. Métodos. Las nanopartículas calcificantes se cultivaron a partir de seis válvulas aórticas seleccionadas aleatoriamente de entre 84 válvulas aórticas explantadas consecutivamente, como se ha descrito en la literatura. Se obtuvieron espectros 1H-RMN de los medios de cultivo de las nanopartículas calcificantes para evaluar posibles cambios metabólicos; mediante reacción en cadena de la polimerasa en tiempo real, se investigó la presencia de 16sRNA. Resultados. A las 6 semanas de cultivo, la presencia de nanopartículas calcificantes se observa claramente como una monocapa unida a la superficie del frasco de cultivo. Todas las muestras resultaron negativas para la presencia de 16sRNA, lo que descartó la presencia de bacterias conocidas en los cultivos. Los espectros 1H-RMN no mostraron diferencias entre los cultivos de nanopartículas calcificantes y medio de cultivo estéril en las mismas condiciones. Conclusiones. Nuestros resultados demuestran que no se puede considerar organismos vivos a las nanopartículas calcificantes (AU)

Introduction and objectives. Calcifying nanoparticles, also known as "nanobacteria", are very small bacteria-like structures (0.1-0.5μm) with the ability to facilitate the precipitation and growth of calcium phosphate in pathological conditions and have been associated with aortic valve calcification. The status of nanobacteria is controversial; some have proposed that they are a new class of living organism while others describe calcifying nanoparticles as mineralo-fetuin complexes. The objective of the present study is to elucidate if calcifying nanoparticles are living entities, based on whether or not they have metabolic activity, a characteristic of life, irrespective of their composition. Methods. Calcifying nanoparticles were grown from 6 different valves randomly chosen among 84 consecutively explanted aortic valves, as described in the literature. The 1H-NMR spectra were acquired from calcifying nanoparticles culture media to assess metabolic changes and the presence of 16sRNA in the culture media was investigated by real-time polymerase chain reaction. Results. After 6 weeks in culture, calcifying nanoparticles could be seen clearly attached to the surface of culture flasks. All samples were negative for 16sRNA, discarding the presence of known bacteria. 1H-NMR spectra showed no difference between calcifying nanoparticles and 6-week-old sterile culture media maintained under the same conditions. Conclusions. Our results show that calcifying nanoparticles cannot be considered as living organisms (AU)

Variación de la epidemiología de las fungemias y de la sensibilidad al fluconazol de los aislamientos de hemocultivos en los últimos 10 años en España: resultados del estudio FUNGEMYCA / Changes in the epidemiology of fungaemia and fluconazole susceptibility of blood isolates during the last 10 years in Spain: results from the FUNGEMYCA study

Antecedentes. Recientemente se ha observado un incremento de las fungemias causadas por especies diferentes de Candida albicans y una disminución de la sensibilidad de los microorganismos responsables al fluconazol. Objetivos. Evaluar la epidemiología y la sensibilidad al fluconazol de los casos de fungemia en España en 2009, comparando los resultados con los obtenidos entre los años 1997-1999 (Pemán J, et al. Eur J Clin Microbiol Infect Dis. 2005). Métodos. Estudio prospectivo multicéntrico con 44 centros participantes realizado desde enero de 2009 a febrero de 2010. Los aislamientos fúngicos procedentes de hemocultivo fueron recogidos en cada centro, donde se realizó el estudio de sensibilidad antifúngica mediante microdilución colorimétrica (Sensititre Yeast One). Resultados. Desde enero de 2009 a febrero de 2010 se recogieron 1.377 aislamientos en hemocultivos, correspondientes a 1.357 episodios de fungemia. Las fungemias se observaron principalmente en mayores de 64 años (46,7%) y el 8,6% en menores de 1 año. C. albicans (44,7%), Candida parapsilosis (29,1%), Candida glabrata (11,5%), Candida tropicalis (8,2%) y Candida krusei (1,9%) fueron las especies más frecuentes, pero su distribución no fue geográficamente homogénea. En los últimos 10 años la incidencia de C. albicans ha aumentado significativamente en Cataluña (39,1 vs. 54,7%, P=0,03) y reducido en la Comunidad Valenciana (49,1 vs. 34,6%, P=0,01). C. parapsilosis ha disminuido en Cataluña (29 vs. 12,4%, P=0,002) y Extremadura (58,3 vs. 20%, P=0,01). La sensibilidad a fluconazol fue similar en toda España pero en los aislamientos de C. albicans la resistencia fue diez veces superior en mayores de 64 años. Sin embargo, la tasa de resistencia (CMI > 32 mg/L) global ha disminuido con respecto a la obtenida hace 10 años (3,7 vs. 2,5% actual), sobre todo en C. albicans (3 vs. 1,6%). Conclusiones. En los últimos 10 años la distribución de las especies causantes de fungemia en España y la sensibilidad al fluconazol no han variado significativamente, aunque se observa una menor tasa de resistencia. La distribución de las especies varía según la unidad de hospitalización, hospital y Comunidad Autónoma(AU)

Background. Recent epidemiological surveillance studies have reported an increase in fungaemia caused by non-Candida albicans species, as well as a decrease in fluconazole susceptibility. Objectives. To evaluate changes in the epidemiology of fungaemia in Spain comparing data from a new surveillance epidemiological study conducted in 2009 with a previous study carried out from 1997 to 1999 (Pemán J, et al. Eur J Clin Microbiol Infect Dis. 2005). Methods. From January 2009 to February 2010, 44 Spanish hospitals participated in a prospective multicentre fungaemia surveillance study to ascertain whether there have been changes in the epidemiology and fluconazole susceptibility. Susceptibility was determined by the colorimetric method Sensititre Yeast One. Demographic and clinical data and the first isolate of each episode were gathered. Results. A total of 1,377 isolates from 1,357 fungaemia episodes were collected, 46.7% from patients older than 64years and 8.6% from children less than 1 year old. C. albicans (44.7%), Candida parapsilosis (29.1%), Candida glabrata (11.5%), Candida tropicalis (8.2%), and Candida krusei (1.9%) were the most frequent species isolated. Distribution varied with the geographical area. C. albicans incidence has increased significantly in the last 10years in Cataluña (39.1 vs. 54.7%, P =0.03) and decreased in the Valencian Community (49.1 vs. 34.6%, P =0.002) and Extremadura (58.3 vs. 20%, P =0.01). Susceptibility to fluconazole was similar for all geographical areas, although resistance in C. albicans was ten times greater for patients aged more than 64years. The overall rate of fluconazole resistance (MIC > 32 mg/L) has decreased with respect to that obtained 10years ago (3.7 vs. 2.5%) mainly in C. albicans (3 vs. 1.6%). Conclusions. In the last ten years, species distribution and fluconazole susceptibility have not significantly changed, although a lower rate of fluconazole resistance has been observed. Species distribution varies with hospital, hospitalization Unit and geographical area(AU)