Efficacy of delafloxacin alone and incombination with cefotaxime againstcefotaxime non-susceptible invasive isolatesof Streptococcus pneumoniae / Eficacia de delafloxacino solo y en combinación con cefotaxima frente a aislados invasivos de Streptococcus pneumoniae no sensible acefotaxima

Objectives. We assessed the in vitro activity of delafloxacin and the synergy between cefotaxime and delafloxacin among cefotaxime non-susceptible invasive isolates of Streptococcus pneumoniae (CNSSP). Material and methods. A total of 30 CNSSP (cefotaxime MIC > 0.5 mg/L) were studied. Serotyping was performed by the Pneumotest-Latex and Quellung reaction. Minimum inhibitory concentrations (MICs) of delafloxacin, levofloxacin, penicillin, cefotaxime, erythromycin and vancomycin were determined by gradient diffusion strips (GDS). Synergistic activity of delafloxacin plus cefotaxime against clinical S. pneumoniae isolates was evaluated by the GDS cross method. Results. Delafloxacin showed a higher pneumococcal activity than its comparator levofloxacin (MIC50, 0.004 versus 0.75 mg/L and MIC90, 0.047 versus >32 mg/L). Resistance to delafloxacin was identified in 7/30 (23.3%) isolates, belonging to serotypes 14 and 9V. Synergy between delafloxacin and cefotaxime was detected in 2 strains (serotypes 19A and 9V). Antagonism was not observed. Addition of delafloxacin increased the activity of cefotaxime in all isolates. Delafloxacin susceptibility was restored in 5/7 (71.4%) strains. Conclusions. CNSSP showed a susceptibility to delafloxacin of 76.7%. Synergistic interactions between delafloxacin and cefotaxime were observed in vitro among CNSSP by GDS cross method. (AU)

Objetivos. Evaluamos la actividad in vitro de delafloxacino y la sinergia entre cefotaxima y delafloxacino entre aislados invasivos de Streptococcus pneumoniae no sensibles a cefotaxima (SPNSC). Material y métodos. Se estudiaron un total de 30 SPNSC (CIM de cefotaxima > 0,5 mg/L). El serotipado se realizó mediante la reacción Pneumotest-Latex y Quellung. Las concentraciones mínimas inhibitorias (CMI) de delafloxacino, levofloxacino, penicilina, cefotaxima, eritromicina y vancomicina se determinaron mediante tiras de difusión en gradiente (GDS). La actividad sinérgica de delafloxacino y cefotaxima frente aislados clínicos de S. pneumoniae se evaluó mediante el método cruzado GDS. Resultados. Delafloxacino mostró una mayor actividad neumocócica que su comparador levofloxacino (CIM50, 0,004 versus 0,75 mg/L y MIC90, 0,047 versus > 32 mg/L). Se identificó resistencia a delafloxacino en 7/30 (23,3%) aislados, pertenecientes a los serotipos 14 y 9V. Se detectó sinergia entre delafloxacino y cefotaxima en 2 cepas (serotipos 19A y 9V). No se observó antagonismo. La adición de delafloxacino aumentó la actividad de cefotaxima en todos los aislados. La sensibilidad a delafloxacino se restableció en 5/7 (71,4%) cepas. Conclusiones. SPNSC mostraron una susceptibilidad a delafloxacino del 76,7%. Se observaron interacciones sinérgicas in vitro entre delafloxacino y cefotaxima entre SPNSC mediante el método cruzado GDS. (AU)

Adult T-cell leukemia/lymphoma in HTLV-1 non-endemic regions.

BACKGROUND: HTLV-1 infection is a neglected disease, despite producing neurological and lymphoproliferative severe illnesses and affect over 10 million people worldwide. Roughly 5% of HTLV-1 carriers develop Adult T-cell leukemia/lymphoma (ATLL), one of the most aggressive hematological malignancies. METHODS: A national HTLV-1 register exists since 1989 in Spain, a non-endemic country with a large migrant flow from Latin America and Equatorial Africa, where HTLV-1 is endemic. The main features of all patients diagnosed with ATLL in Spain up to date are reported. RESULTS: A total of 451 cases of HTLV-1 infection had been reported in Spain until the end of year 2022. ATLL had been diagnosed in 35 (7.8%). The current average incidence of ATLL in Spain is of two cases per year. Women represent 57% of ATLL patients. Mean age at diagnosis was 47 years-old. Roughly 57% were Latin Americans and 26% Africans. At diagnosis, the majority presented with acute or lymphoma clinical forms. Survival was shorter than one year in most of them. Mean HTLV-1 proviral load was significantly greater in ATLL patients than in asymptomatic HTLV-1 carriers (2,305 vs 104 copies/104 PBMC). HTLV-1 subtyping in 6 ATLL patients found the 1a transcontinental variant (n = 4) and the Japanese variant (n = 2). All ATLL patients were negative for HIV-1, did not develop HTLV-1-associated myelopathy and were not transplant recipients. CONCLUSION: The rate of ATLL is very low in Spain and mostly associated to migrants from HTLV-1 endemic regions. Given the poor clinical outcome of ATLL, HTLV-1 testing should be performed at least once in all migrants coming from HTLV-1 endemic countries and in natives who have lived in or had sex partners from such regions.

Evolution of antibody titers after two doses of mRNA Pfizer-BioNTech vaccine and effect of the third dose in nursing home residents.

OBJECTIVES: We evaluated the IgG antibody titer against SARS-CoV-2 in 196 residents of a Spanish nursing home after the second dose of the BNT162b2 vaccine and the evolution of this titer over time. The role of the third dose of the vaccine on immune-response is also analysed in 115 of participants. METHODS: Vaccine response was evaluated 1, 3 and 6 months after second dose of Pfizer-BioNTech COVID-19 Vaccine and 30 days after booster vaccination. Total anti-RBD (receptor binding domain) IgG immunoglobulins were measured to assess response. Six month after the second dose of vaccine and previously to the booster, T-cell response was also measured in 24 resident with different antibody levels. T-spot Discovery SARS-CoV-2 kit was used to identify cellular immunogenicity. RESULTS: As high as 99% of residents demonstrated a positive serological response after second dose. Only two patients showed no serologic response, two men without records of previous SARS-CoV-2 infection. A higher immune response was associated with prior SARS-CoV-2 infection regardless of the gender or age. The anti-S IgG titers decreased significantly in almost all the participants (98.5%) after six months of vaccination whatever previous COVID-infection. The third dose of vaccine increased antibody titers in all patients, although initial vaccination values were not restored in the majority of cases. CONCLUSION: The main conclusion of the study is that vaccine resulted in good immunogenicity in this vulnerable population. Nevertheless more data are needed on the long-term maintenance of antibody response after booster vaccination.

Resistance to fosfomycin is increasing and is significantly associated with extended-spectrum ß-lactamase-production in urinary isolates of Escherichia coli.

Fosfomycin has become a therapeutic option in urinary tract infections. Our objective was to evaluate the in vitro activity of fosfomycin against Escherichia coli isolated from urine samples in 2013, 2018 and 2021. We also determined a putative association between fosfomycin resistance and extended-spectrum ß-lactamases (ESBL) production. Fosfomycin activity was evaluated against 7367, 8128 and 5072 Escherichia coli urinary isolates in 2013, 2018 and 2021, respectively. We compare the prevalence of fosfomycin-resistant strains among the ESBL- and non-ESBL-producing isolates. MICs of fosfomycin, cefotaxime, and cefotaxime-clavulanate were determined by a microdilution method. 302 ESBL-producers were selected to determine MICs of fosfomycin by agar dilution and genes encoding ESBLs were detected by PCR. Among the total of ESBL-producing strains, 14.3%, 20.8% and 20% were resistant to fosfomycin in 2013, 2018 and 2021, respectively, whereas fosfomycin resistance in non-ESBL producers was 3.5%, 4.05% and 5.53% for each year (P ≤ 0.001). In the 302 selected ESBL-producing isolates, CTX-M was the main ESBL (228 isolates), being 50.7% CTX-M-15. Resistance to fosfomycin among these ESBL-producing strains was associated (P = 0.049) with isolates that produced the CTX-M type. Our data show that fosfomycin resistance is increasing in Escherichia coli urinary isolates and it is related to ESBL-production. A follow-up of fosfomycin resistance is required.

Comparison of performance of MALDI-TOF MS and MLST for biotyping carbapenemase-producing Klebsiella pneumoniae sequence types ST11 and ST101 isolates.

INTRODUCTION: The rapid identification and detection of carbapenemase-producing Klebsiella pneumoniae (CPKP) isolates is crucial to ascertain outbreaks, as well as to limit their spread. The current reference method for this purpose is multilocus sequence typing (MLST), which is laborious and expensive. Consequently, alternative typing methods are gaining attention, such as Matrix-Assisted Laser Desorption Ionization-Time Of Flight Mass Spectrometry (MALDI-TOF MS). METHODS: This study sought to analyze MALDI-TOF MS as a typing method using 44 CPKP isolates that were well characterized by MLST. The most common types of samples from which these pathogens were isolated were skin and soft tissues (32%) and urine (29%). Half of the CPKP isolates were from hospitalized patients. Two approaches were followed for the analysis of the mass peak data obtained by MALDI-TOF MS. The first using all peaks obtained and the second using a selection of 21 characteristic peaks. RESULTS: The selection of 21 characteristic peaks showed greater discrimination power for ST11 and ST101. Principal component analysis (PCA) indicated that this dataset could be efficiently grouped with lineal classifiers. A Support Vector Machine (SVM) was chosen for this purpose after checking its capacity to classify bacterial strains on the basis of MALDI-TOF MS information. CONCLUSION: SVM was able to discriminate between ST11 and ST101 with high accuracy. In conclusion, our results reveal MALDI-TOF MS as a promising alternative technique for typing of CPKP isolates.

Comparison of performance of MALDI-TOF MS and MLST for biotyping carbapenemase-producing Klebsiella pneumoniae sequence types ST11 and ST101 isolates / Estudio comparativo de la utilidad de MALDI-TOF MS y MLST para el biotipado de Klebsiella pneumoniae ST11 y ST101 productoras de carbapenemasas

IntroductionThe rapid identification and detection of carbapenemase-producing Klebsiella pneumoniae (CPKP) isolates is crucial to ascertain outbreaks, as well as to limit their spread. The current reference method for this purpose is multilocus sequence typing (MLST), which is laborious and expensive. Consequently, alternative typing methods are gaining attention, such as Matrix-Assisted Laser Desorption Ionization–Time Of Flight Mass Spectrometry (MALDI-TOF MS).MethodsThis study sought to analyze MALDI-TOF MS as a typing method using 44 CPKP isolates that were well characterized by MLST. The most common types of samples from which these pathogens were isolated were skin and soft tissues (32%) and urine (29%). Half of the CPKP isolates were from hospitalized patients. Two approaches were followed for the analysis of the mass peak data obtained by MALDI-TOF MS. The first using all peaks obtained and the second using a selection of 21 characteristic peaks.ResultsThe selection of 21 characteristic peaks showed greater discrimination power for ST11 and ST101. Principal component analysis (PCA) indicated that this dataset could be efficiently grouped with lineal classifiers. A Support Vector Machine (SVM) was chosen for this purpose after checking its capacity to classify bacterial strains on the basis of MALDI-TOF MS information.ConclusionSVM was able to discriminate between ST11 and ST101 with high accuracy. In conclusion, our results reveal MALDI-TOF MS as a promising alternative technique for typing of CPKP isolates.

IntroducciónLa rápida identificación y detección de los aislados de Klebsiella pneumoniae productores de carbapenemasas (CPKP) es crucial para identificar brotes e impedir la propagación de los aislados resistentes. El método de referencia para este propósito es el multilocus sequencing typing (MLST), que es un técnica laboriosa y cara, por lo que se buscan métodos de tipado alternativos que pueden desempeñar la misma función con menor esfuerzo. Entre las posibles técnicas se encuentra la espectrometría de masas de tiempo de vuelo MALDI-TOF.MétodosEste estudio se han utilizado el sistema MALDI-TOF MS para tipar 44 aislamientos de CPKP previamente caracterizados por MLST. Las muestras clínicas de las que proceden los aislados son principalmente piel y tejidos blandos (32%) y orina (29%). La mitad de los aislamientos de CPKP procedían de pacientes ingresados. El análisis los datos obtenidos por MALDI-TOF MS se realizó con 2 enfoques diferentes, el primero usando todos los picos obtenidos y el segundo usando una selección de picos.ResultadosLa selección de 21 picos característicos ofreció un mayor poder de discriminación entre ST11 y ST101. El análisis de componentes principales (PCA) indicó que este conjunto de datos podría agruparse eficientemente con clasificadores lineales. Para realizar este agrupamiento se escogió el algoritmo support vector machine (SVM, máquinas de vectores de soporte) para este propósito después de verificar su capacidad para clasificar las cepas bacterianas en base a la información de MALDI-TOF MS.ConclusiónSVM pudo discriminar entre ST11 y ST101 con alta precisión. En conclusión, nuestros resultados revelan MALDI-TOF MS puede ser una técnica alternativa para el tipificación de aislamientos de CPKP.

Identification of CRF66_BF, a New HIV-1 Circulating Recombinant Form of South American Origin.

Circulating recombinant forms (CRFs) are important components of the HIV-1 pandemic. Among 110 reported in the literature, 17 are BF1 intersubtype recombinant, most of which are of South American origin. Among these, all 5 identified in the Southern Cone and neighboring countries, except Brazil, derive from a common recombinant ancestor related to CRF12_BF, which circulates widely in Argentina, as deduced from coincident breakpoints and clustering in phylogenetic trees. In a HIV-1 molecular epidemiological study in Spain, we identified a phylogenetic cluster of 20 samples from 3 separate regions which were of F1 subsubtype, related to the Brazilian strain, in protease-reverse transcriptase (Pr-RT) and of subtype B in integrase. Remarkably, 14 individuals from this cluster (designated BF9) were Paraguayans and only 4 were native Spaniards. HIV-1 transmission was predominantly heterosexual, except for a subcluster of 6 individuals, 5 of which were men who have sex with men. Ten additional database sequences, from Argentina (n = 4), Spain (n = 3), Paraguay (n = 1), Brazil (n = 1), and Italy (n = 1), branched within the BF9 cluster. To determine whether it represents a new CRF, near full-length genome (NFLG) sequences were obtained for 6 viruses from 3 Spanish regions. Bootscan analyses showed a coincident BF1 recombinant structure, with 5 breakpoints, located in p17 gag , integrase, gp120, gp41-rev overlap, and nef, which was identical to that of two BF1 recombinant viruses from Paraguay previously sequenced in NFLGs. Interestingly, none of the breakpoints coincided with those of CRF12_BF. In a maximum likelihood phylogenetic tree, all 8 NFLG sequences grouped in a strongly supported clade segregating from previously identified CRFs and from the CRF12_BF "family" clade. These results allow us to identify a new HIV-1 CRF, designated CRF66_BF. Through a Bayesian coalescent analysis, the most recent common ancestor of CRF66_BF was estimated around 1984 in South America, either in Paraguay or Argentina. Among Pr-RT sequences obtained by us from HIV-1-infected Paraguayans living in Spain, 14 (20.9%) of 67 were of CRF66_BF, suggesting that CRF66_BF may be one of the major HIV-1 genetic forms circulating in Paraguay. CRF66_BF is the first reported non-Brazilian South American HIV-1 CRF_BF unrelated to CRF12_BF.

Identification of CRF89_BF, a new member of an HIV-1 circulating BF intersubtype recombinant form family widely spread in South America.

Circulating recombinant forms (CRFs) contribute substantially to the HIV-1 pandemic. Among 105 CRFs described in the literature, 16 are BF intersubtype recombinants, most of South American origin, of which CRF12_BF is the most widely spread. A BF recombinant cluster identified in Bolivia was suggested to represent a new CRF_BF. Here we find that it belongs to a larger cluster incorporating 39 viruses collected in 7 countries from 3 continents, 22 of them in Spain, most from Bolivian or Peruvian individuals, and 12 in South America (Bolivia, Argentina, and Peru). This BF cluster comprises three major subclusters, two associated with Bolivian and one with Peruvian individuals. Near full-length genome sequence analyses of nine viruses, collected in Spain, Bolivia, and Peru, revealed coincident BF mosaic structures, with 13 breakpoints, 6 and 7 of which coincided with CRF12_BF and CRF17_BF, respectively. In a phylogenetic tree, they grouped in a clade closely related to these CRFs, and more distantly to CRF38_BF and CRF44_BF, all circulating in South America. These results allowed to identify a new HIV-1 CRF, designated CRF89_BF. Through phylodynamic analyses, CRF89_BF emergence was estimated in Bolivia around 1986. CRF89_BF is the fifth CRF member of the HIV-1 recombinant family related to CRF12_BF.

Comparison of performance of MALDI-TOF MS and MLST for biotyping carbapenemase-producing Klebsiella pneumoniae sequence types ST11 and ST101 isolates.

INTRODUCTION: The rapid identification and detection of carbapenemase-producing Klebsiella pneumoniae (CPKP) isolates is crucial to ascertain outbreaks, as well as to limit their spread. The current reference method for this purpose is multilocus sequence typing (MLST), which is laborious and expensive. Consequently, alternative typing methods are gaining attention, such as Matrix-Assisted Laser Desorption Ionization-Time Of Flight Mass Spectrometry (MALDI-TOF MS). METHODS: This study sought to analyze MALDI-TOF MS as a typing method using 44 CPKP isolates that were well characterized by MLST. The most common types of samples from which these pathogens were isolated were skin and soft tissues (32%) and urine (29%). Half of the CPKP isolates were from hospitalized patients. Two approaches were followed for the analysis of the mass peak data obtained by MALDI-TOF MS. The first using all peaks obtained and the second using a selection of 21 characteristic peaks. RESULTS: The selection of 21 characteristic peaks showed greater discrimination power for ST11 and ST101. Principal component analysis (PCA) indicated that this dataset could be efficiently grouped with lineal classifiers. A Support Vector Machine (SVM) was chosen for this purpose after checking its capacity to classify bacterial strains on the basis of MALDI-TOF MS information. CONCLUSION: SVM was able to discriminate between ST11 and ST101 with high accuracy. In conclusion, our results reveal MALDI-TOF MS as a promising alternative technique for typing of CPKP isolates.

Panuveitis and Optic Neuritis as a Possible Initial Presentation of the Novel Coronavirus Disease 2019 (COVID-19).

OBJECTIVE: To describe the ocular manifestations in a case of novel coronavirus disease 2019 (COVID-19). MATERIAL AND METHODS: A case of unilateral panuveitis and optic neuritis as initial presentation of COVID-19. RESULTS: As it is published, angiotensin-converting-enzyme-2 receptors can be found in many organs, such as the eyes, nerves, and vessels, so extrapulmonary involvement would be expected. According to current evidence and clinical characteristics of the patient, uveitis and optic neuritis could be produced by the virus. CONCLUSIONS: It is fundamental to consider panuveitis and optic neuritis as an unusual presentation of ocular involvement in COVID-19 so proper care can be given to the patients.

Synergy of Linezolid with Several Antimicrobial Agents against Linezolid-Methicillin-Resistant Staphylococcal Strains.

Linezolid is a synthetic oxazolydinone active against multi-resistant Gram-positive cocci that inhibits proteins synthesis by interacting with the 50S ribosomal subunit. Although linezolid-resistant strains are infrequent, several outbreaks have been recently described, associated with prolonged treatment with the antibiotic. As an alternative to monotherapy, the combination of different antibiotics is a commonly used option to prevent the selection of resistant strains. In this work, we evaluated combinations of linezolid with classic and new aminoglycosides (amikacin, gentamicin and plazomicin), carbapenems (doripenem, imipenem and meropenem) and fosfomycin on several linezolid- and methicillin-resistant strains of Staphylococcus aureus and S. epidermidis, isolated in a hospital intensive care unit in Madrid, Spain. Using checkerboard and time-kill assays, interesting synergistic effects were encountered for the combination of linezolid with imipenem in all the staphylococcal strains, and for linezolid-doripenem in S.epidermidis isolates. The combination of plazomicin seemed to also have a good synergistic or partially synergistic activity against most of the isolates. None of the combinations assayed showed an antagonistic effect.

Increase of serotype 8, ST53 clone, as the prevalent strain of Streptococcus pneumoniae causing invasive disease in Madrid, Spain (2012-2015) / Incremento del serotipo 8, clon ST53, como la cepa más prevalente causante de enfermedad neumocócica invasora en Madrid, España (2012-2015)

INTRODUCTION: In recent years, Streptococcus pneumoniae serotype 8 has become the most prevalent cause of invasive pneumococcal disease (IPD) in Madrid, Spain. The objective of this study was to characterize the invasive clones of S. pneumoniae serotype 8 in Madrid over the 2012-2015 period. METHODS: From January 2012 to December 2015, a total of 1543 invasive isolates were studied. Serotyping was carried out by Pneumotest-Latex agglutination and Quellung reaction. Susceptibilities to penicillin, erythromycin and levofloxacin were determined by the Etest®. All serotype 8 strains were typed by multilocus sequence typing (MLST) and by pulsed-field gel electrophoresis (PFGE). RESULTS: Two hundred and forty-eight (248) serotype 8 strains were detected (16.1%) and 243 of them were available for molecular typing. Nine sequence types (STs) by MLST (8-ST53, 8-ST63, 8-ST404, 8-ST1107, 8-ST989, 8-ST1110, 8-ST2231, 8-ST3544 and 8-ST4301), and nine PFGE profiles were identified (one corresponding to each ST). The 8-ST53 clone was the most widespread, and increased from 53.8% among all serotype 8 isolates in 2012, to 90.1% in 2015. In contrast, the 8-ST63 clone, resistant to levofloxacin and erythromycin, decreased from 30.8%, among all serotype 8 strains in 2012, to 5.0% in 2015. CONCLUSIONS: The increase in our region of S. pneumoniae serotype 8, not included in conjugated vaccines, occurred at the expense of the 8-ST53 clone. On the contrary, the 8-ST63 clone decreased. Since clone 8-ST63 has the theoretical advantage of its levofloxacin-erythromycin resistance in comparison to 8-ST53, the predominance of 8-ST53 over 8-ST63 is striking

INTRODUCCIÓN: En los últimos años Streptococcus pneumoniae serotipo 8 ha sido la causa más prevalente de enfermedad neumocócica invasora (ENI) en la Comunidad de Madrid. El objetivo de este estudio fue caracterizar los clones invasores de S. pneumoniae serotipo 8 circulantes en Madrid ente los años 2012 y 2015. MÉTODOS: Se estudiaron 1.543 cepas causantes de ENI aisladas entre enero de 2012 y diciembre de 2015. El serotipado se realizó mediante aglutinación con Pneumotest-Latex y reacción de Quellung. La determinación de la sensibilidad frente a penicilina, eritromicina y levofloxacino se realizó mediante Etest(R). Las cepas del serotipo 8 se tipificaron por MLST (multi-locus sequence typing) y electroforesis en campo pulsado (PFGE). RESULTADOS: Se detectaron 248 cepas del serotipo 8 (16,1%) y 243 de ellas estuvieron disponibles para tipado molecular. Se identificaron 9 tipos de ST: 8-ST53, 8-ST63, 8-ST404, 8-ST1107, 8-ST989, 8-ST1110, 8-ST2231, 8-ST3544 y 8-ST4301, y 9 perfiles de PFGE (uno correspondiente a cada ST). El clon 8-ST53 fue el más prevalente dentro del serotipo 8 y aumentó del 53,8% en 2012 al 90,1% en 2015. Por el contrario el clon 8-ST63 asociado con resistencia a levofloxacino y eritromicina disminuyó del 30,8% en 2012 al 5,0% en 2015. CONCLUSIONES: El incremento del serotipo 8 en nuestra región, no cubierto por las actuales vacunas conjugadas, se produjo a expensas del clon 8-ST53. Inversamente, el clon 8-ST63 disminuyó. Dado que el clon 8-ST63 presenta sobre el 8-ST53 la ventaja teórica de su resistencia frente a levofloxacino y eritromicina, resulta llamativo el predominio de 8-ST53 sobre 8-ST63

Increase of serotype 8, ST53 clone, as the prevalent strain of Streptococcus pneumoniae causing invasive disease in Madrid, Spain (2012-2015).

INTRODUCTION: In recent years, Streptococcus pneumoniae serotype 8 has become the most prevalent cause of invasive pneumococcal disease (IPD) in Madrid, Spain. The objective of this study was to characterize the invasive clones of S. pneumoniae serotype 8 in Madrid over the 2012-2015 period. METHODS: From January 2012 to December 2015, a total of 1543 invasive isolates were studied. Serotyping was carried out by Pneumotest-Latex agglutination and Quellung reaction. Susceptibilities to penicillin, erythromycin and levofloxacin were determined by the Etest®. All serotype 8 strains were typed by multilocus sequence typing (MLST) and by pulsed-field gel electrophoresis (PFGE). RESULTS: Two hundred and forty-eight (248) serotype 8 strains were detected (16.1%) and 243 of them were available for molecular typing. Nine sequence types (STs) by MLST (8-ST53, 8-ST63, 8-ST404, 8-ST1107, 8-ST989, 8-ST1110, 8-ST2231, 8-ST3544 and 8-ST4301), and nine PFGE profiles were identified (one corresponding to each ST). The 8-ST53 clone was the most widespread, and increased from 53.8% among all serotype 8 isolates in 2012, to 90.1% in 2015. In contrast, the 8-ST63 clone, resistant to levofloxacin and erythromycin, decreased from 30.8%, among all serotype 8 strains in 2012, to 5.0% in 2015. CONCLUSIONS: The increase in our region of S. pneumoniae serotype 8, not included in conjugated vaccines, occurred at the expense of the 8-ST53 clone. On the contrary, the 8-ST63 clone decreased. Since clone 8-ST63 has the theoretical advantage of its levofloxacin-erythromycin resistance in comparison to 8-ST53, the predominance of 8-ST53 over 8-ST63 is striking.

Comparative evaluation of plazomicin MICs obtained using agar dilution versus broth microdilution methods and impact of inoculum size against ESBL-producing Escherichia coli, carbapenemase-producing Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus clinical isolates.

MICs of plazomicin were determined by agar dilution and broth microdilution in 187 ESBL-producing Escherichia coli (n = 73), carbapenemase-producing Klebsiella pneumoniae (n = 55) methicillin-resistant Staphylococcus aureus (n = 59) clinical isolates. Inoculum effect was determined by broth microdilution assay using two different inocula; 1-5 × 105 (standard inoculum) and 1-5 × 108 CFU/mL. For all isolates tested >98% categorical agreement and ≥95% of essential agreement (±1elog2) was found. At high inocula, MICs of plazomicin increased ≥ eight-fold for 25% of E. coli, 24% of K. pneumoniae and 7% of S. aureus isolates tested. The results indicate that agar dilution and broth microdilution methods were equally suitable for determining plazomicin MICs. Inoculum effect was observed for plazomicin in Escherichia coli and Klebsiella pneumoniae isolates. Further studies that establish the genetic background of the isolates are required to better understand the reasons behind the inoculum effect.

Description of carbapenemase-producing Enterobacteriaceae isolates in a Spanish tertiary hospital. Epidemiological analysis and clinical impact / Descripción de los aislamientos de enterobacterias productoras de carbapenemasa en un hospital terciario. Análisis epidemiológico e impacto clínico

OBJECTIVES: The aim of the study was to carry out an epidemiological analysis of patients with carbapenemase-producing Enterobacteriaceae (CPE) isolations in our hospital as well as to perform a description of the genotypic temporal evolution of CPE isolated. MATERIAL AND METHODS: An observational prospective cohort study was performed involving all patients with CPE isolates from clinical samples during November 2014 to November 2016 in a Spanish teaching hospital. Patients were clinically evaluated and classified either as infected or colonized. Information on the consumption of carbapenems in the hospital during the study period was also analyzed. PCR was used for identification of the carbapenemase genes blaKPC, blaVIM, and blaOXA-48. RESULTS: A total of 301 CPE isolates were obtained (107 in 2014, 89 in 2015 and 105 in 2016). Klebsiella pneumoniae (73.4%) was the most prevalent microorganism. Hundred and seventy (56.7%) of carbapenemases detected were blaOXA-48, 73 (24.3%) were blaKPC and 57 (19%) were blaVIM. In year 2014 KPC was predominant while in 2016 OXA-48 predominated. In 2014 we observed a significant association between the medical wards and the ICU with a higher prevalence of OXA-48 (OR 4.15; p < 0.001) and VIM (OR 7.40; p < 0.001) in the univariate analysis, in the following years there was no association. Regarding the clinical significance of microbiological results after assessing our patients, 60% of isolates represented infection and 40% behaved as colonizers. One third of hospitalized patients with CPE isolation died within 30 days, regardless of whether they were colonized or infected. CONCLUSIONS: We have observed an epidemiological change in the genotypes of our isolates along the study period. A thorough knowledge of the CPE's epidemiological distribution in each hospital is fundamental for optimizing antimicrobial chemotherapy

OBJETIVOS: Se realizó un análisis epidemiológico de aquellos pacientes con aislamiento de Enterobacterias portadoras de carbapenemasas (EPC) en un hospital terciario, así como una descripción temporal de los genotipos de dichas EPC. MATERIAL Y MÉTODOS: Estudio de cohortes prospectivo observacional que incluyó todos los aislamientos de EPC obtenidos de muestras clínicas entre noviembre de 2014 y noviembre de 2016 en un hospital universitario. Los pacientes fueron evaluados clínicamente para determinar si el aislamiento era en el contexto de una infección o de una colonización. También se recopiló la información acerca del consumo de carbapenémicos en el hospital durante el periodo de estudio. Se usó la técnica PCR para la identificación de los genes de carbapenemasas blaKPC, blaVIM, and blaOXA-48. RESULTADOS: Se obtuvieron un total de 301 aislamientos de EPC (107 en 2014, 89 en 2015 y 105 en 2016). Klebsiella pneumoniae (73,4%) fue el microorganismo más prevalente. De las carbapenemasas aisladas, 170 (56,7%) correspondieron a blaOXA-48, 73 (24,3%) a blaKPC y 57 (19%) a blaVIM. En el año 2014 KPC fue la predominante mientras que en 2016 lo fue OXA-48. En 2014 la prevalencia de OXA-48 (OR 4,15;p < 0,001) y de VIM (OR 7,40; p < 0,001) fue significativamente mayor en las áreas médicas y en la UCI en el análisis univariante, sin embargo en los siguientes años no hubo ninguna asociación. Respecto a la significación clínica de los resultados microbiológicos, un 60% de los aislamientos correspondían a una infección y un 40% a una colonización. Un tercio de los pacientes hospitalizados con aislamiento para EPC murieron en los 30 días siguientes al mismo, independientemente de si representaba una colonización o una infección. CONCLUSIONES: Hemos constatado un cambio en el patrón epidemiológico de los genotipos de nuestros aislamientos a lo largo del período de estudio. Un conocimiento pormenorizado de los patrones de distribución epidemiológica de las EPC dentro de cada hospital es fundamental para optimizar la terapéutica antimicrobiana

Identification of Streptococcus pneumoniae lytA, plyA and psaA genes in pleural fluid by multiplex real-time PCR / Identificación de los genes lytA, plyA y psaA de Streptococcus pneumoniae en líquido pleural mediante una técnica de PCR múltiple en tiempo real

INTRODUCTION: The aim was to evaluate the utility of a multiplex real-time PCR to detect Streptococcus pneumoniae lytA, plyA and psaA genes in pleural fluid (PF). METHODS: A collection of 81 PF samples was used. Sixty were considered positive for S. pneumoniae according to previous results (54 by an in-house lytA gene PCR and eight by universal rRNA PCR). RESULTS: The sensitivity for detection of the lytA, plyA and psaA genes by multiplex PCR was 100% (60/60), 98.3% (59/60) and 91.7% (55/60), respectively. The detection of all three genes was negative in 21 samples formerly confirmed as negative for S. pneumoniae (100% specificity) by the other procedures (9 by in-house lytA PCR and 12 by rRNA PCR). CONCLUSIONS: The use of this multiplex PCR may be a useful option to identify S. pneumoniae directly in PF samples

INTRODUCCIÓN: El objetivo fue evaluar la utilidad de una técnica de PCR múltiple para detectar los genes lytA, plyA y psaA de Streptococcus pneumoniae en líquido pleural. MÉTODOS: Se empleó una colección de 81 muestras de líquido pleural. Sesenta habían sido consideradas positivas para S. pneumoniae según resultados previos (54 por una prueba casera de PCR para el gen lytA y 8 por una PCR universal rRNA). RESULTADOS: La sensibilidad de la técnica para la detección de los genes lytA, plyA y psaA fue respectivamente 100% (60/60), 98,3% (59/60) y 91,7% (55/60). La detección de los tres genes resultó negativa en 21 muestras negativas (especificidad 100%) por los otros procedimientos (9 por la prueba casera de PCR para lytA y 12 por la PCR rRNA). CONCLUSIONES: El uso de esta técnica de PCR múltiple puede ser una opción útil para la detección directa de S. pneumoniae en líquido pleural