Plasmids of the incompatibility group FIBK occur in Klebsiella variicola from diverse ecological niches / Los plásmidos del grupo de incompatibilidad FIBK se encuentran en Klebsiella variicola en diversos nichos ecológicos

Plasmids play a fundamental role in the evolution of bacteria by allowing them to adapt to different environments and acquire, through horizontal transfer, genes that confer resistance to different classes of antibiotics. Using the available in vitro and in silico plasmid typing systems, we analyzed a set of isolates and public genomes of K. variicola to study its plasmid diversity. The resistome, the plasmid multilocus sequence typing (pMLST), and molecular epidemiology using the MLST system were also studied. A high frequency of IncF plasmids from human isolates but lower frequency from plant isolates were found in our strain collection. In silico detection revealed 297 incompatibility (Inc) groups, but the IncFIBK (216/297) predominated in plasmids from human and environmental samples, followed by IncFIIK (89/297) and IncFIA/FIA(HI1) (75/297). These Inc groups were associated with clinically important ESBL (CTX-M-15), carbapenemases (KPC-2 and NDM-1), and colistin-resistant genes which were associated with major sequence types (ST): ST60, ST20, and ST10. In silico MOB typing showed 76% (311/404) of the genomes contained one or more of the six relaxase families with MOBF being most abundant. We identified untypeable plasmids carrying blaKPC-2, blaIMP-1, and blaSHV-187 but for which a relaxase was found; this may suggest that novel plasmid structures could be emerging in this bacterial species. The plasmid content in K. variicola has limited diversity, predominantly composed of IncFIBK plasmids dispersed in different STs. Plasmid detection using the replicon and MOB typing scheme provide a broader context of the plasmids in K. variicola. This study showed that whole-sequence-based typing provides current insights of the prevalence of plasmid types and their association with antimicrobial resistant genes in K. variicola obtained from humans and environmental niches.(AU)

Virulence, antimicrobial resistance, and molecular characteristics of carbapenem-resistant Klebsiella pneumoniae in a hospital in Shijiazhuang City from China / Virulencia, resistencia a los antimicrobianos y características moleculares de Klebsiella pneumoniae resistente a carbapenémicos en un hospital de la ciudad de Shijiazhuang de China

Carbapenem-resistant Klebsiella pneumoniae (CRKP), as one of the most common drug-resistant bacteria threatening human health, is hyper-resistant to multiple antimicrobial drugs and carbapenems, which can be dealt with only limited clinical treatment options. This study described the epidemiological characteristics of CRKP in this tertiary care hospital from 2016 to 2020. Specimen sources included blood, sputum, alveolar lavage fluid, puncture fluid, secretions from a burn wound, and urine. Among the 87 carbapenem-resistant strains, ST11 was the predominant isolate, followed by ST15, ST273, ST340, and ST626. These STs were in broad agreement with the STs defined by pulsed-field gel electrophoresis clustering analysis in discriminating clusters of related strains. Most CRKP isolates contained the blaKPC-2 gene, some isolates carried the blaOXA-1, blaNDM-1, and blaNDM-5 genes, and the isolates carrying carbapenem resistance genes were more resistant to the antimicrobials of β-lactams, carbapenems, macrolides, and fluoroquinolone. The OmpK35 and OmpK37 genes were detected in all CRKP strains, and the Ompk36 gene was detected in some CRKP strains. All detected OmpK37 had 4 mutant sites, and OmpK36 had 11 mutant sites, while no mutant sites were found in OmpK35. More than half of the CRKP strains contained the OqxA and OqxB efflux pump genes. The virulence genes were most commonly combined with urea-wabG-fimH-entB-ybtS-uge-ycf. Only one CRKP isolate was detected with the K54 podoconjugate serotype. This study elucidated the clinical epidemiological features and molecular typing of CRKP, and grasped the distribution of drug-resistant genotypes, podocyte serotypes, and virulence genes of CRKP, providing some guidance for the subsequent treatment of CRKP infection.(AU)

Molecular characterization of colistin resistance genes in a high-risk ST101/KPC-2 clone of Klebsiella pneumoniae in a University Hospital of Split, Croatia / Caracterización molecular de genes de resistencia a la colistina en un clon ST101/KPC-2 de alto riesgo de Klebsiella pneumoniae en un Hospital Universitario de Split, Croacia

Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP) has become a major concern worldwide due to multidrug resistance and the ability to spread locally and globally. Infections caused by KPC-KP are great challenge in the healthcare systems because these are associated with longer hospitalization and high mortality. The emergence of colistin resistance has significantly reduced already limited treatment options. This study describes the molecular background of colistin-resistant KPC-KP isolates in the largest hospital in southern Croatia. Thirty-four non-duplicate colistin-resistant KPC-KP isolates were collected during routine work from April 2019 to January 2020 and from February to May 2021. Antimicrobial susceptibility was determined using disk diffusion, broth microdilution, and the gradient strip method. Carbapenemase was detected with an immunochromatographic test. Identification of blaKPC and mcr genes or mutations in pmrA, pmrB, mgrB, phoP, and phoQ genes were performed by polymerase chain reaction (PCR) and positive products were sequenced. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used for epidemiological analysis. All isolates were multidrug-resistant, with colistin minimum inhibitory concentrations (MICs) from 4 to >16 mg/L, and all harbored blaKPC-2 and had a single point mutation in the mgrB gene resulting in a premature stop codon, with the exception of one isolate with four point mutations corresponding to stop codons. All isolates were negative for mcr genes. PFGE analysis identified a single genetic cluster, and MLST revealed that all isolates belonged to sequence type 101 (ST101). These results show emergence of the high-risk ST101/KPC-2 clone of K. pneumoniae in Croatia as well as appearance of colistin resistance due to mutations in the mgrB gene. Molecular analysis of epidemiology and possible resistance mechanisms are important to develop further strategies to combat such threats.(AU)

New paradigms on antibiotic recommendations for community-acquired infections in Spain / Nuevos paradigmas en las recomendaciones antibióticas en las infecciones comunitarias en España

Over the last years, the susceptibility activity of the most common microorganisms causing community-acquired infections has significantly changed in Spain. Based on the susceptibility rates of Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae, Escherichia coli, and Klebsiella pneumoniae collected from outpatients aged 15 or older with symptoms of respiratory or urinary tract infections in several Microbiology Departments in Catalonia in 2021, penicillin V should be first choice for most respiratory tract infections, amoxicillin and clavulanate for chronic obstructive pulmonary disease exacerbations and a single dose of fosfomycin or a short-course nitrofurantoin should remain first-line treatments for uncomplicated urinary tract infections. Updated information on antimicrobial resistance for general practitioners is crucial for achieving appropriate empirical management of the most common infections by promoting more rational antibiotic use.(AU)

En los últimos años han cambiado significativamente los porcentajes de sensibilidad de los microorganismos más comunes que causan infecciones adquiridas en la comunidad en España. A partir de los porcentajes de sensibilidad de Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae, Escherichia coli y Klebsiella pneumoniae, recogidas de aislados de pacientes ambulatorios de 15 años o más, con síntomas de infecciones respiratorias o urinarias en servicios de microbiología de Cataluña en 2021, fenoximetilpenicilina debería ser la primera opción en la mayoría de los infecciones respiratorias, amoxicilina y ácido clavulánico en las exacerbaciones de la enfermedad pulmonar obstructiva crónica y la monodosis de fosfomicina o la pauta corta de nitrofurantoína como tratamiento de primera línea en las infecciones urinarias no complicadas. Es importante que los médicos de familia dispongan de información actualizada sobre la resistencia a los antimicrobianos para lograr un manejo empírico adecuado de las infecciones más frecuentes al promover un uso más racional de los antibióticos.(AU)

Evolution of Antibiotic Resistance in Escherichia coli and Klebsiella pneumoniae from Urine Cultures

Objective: Determine the evolution of antibiotic resistance of symptomatic bacteriuria caused by Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) in Granada. Material and Method: A descriptive retrospective study was carried out, including antibiograms of urine cultures in which microorganisms identified as E. coli and K. pneumoniae, were isolated in the Microbiology laboratory of the Hospital Universitario Virgen de las Nieves (Granada, Spain) between January 2016 and June 2021. Results: E. coli was the most frequent isolate (10,048) and its resistance to ampicillin (59.45%) and ticarcillin (59.59%), and the increase to cefepime (15.07%) and amoxicillin-clavulanic acid (17.67%) is noteworthy. K. pneumoniae (2222) is notable for resistance to Fosfomycin (27.91%) and an increase to ciprofloxacin (37.79%) and amoxicillin-clavulanic acid (36.63%). Resistance is generally higher in hospitalized patients, males, and adults. Conclusions: Antibiotic resistance to the studied Enterobacteriaceae is on the rise, requiring empirical treatment targeted to the population area (AU)

In vitro activity of six biocides against carbapenemase-producing Klebsiella pneumoniae and presence of genes encoding efflux pumps / Actividad in vitro de seis biocidas frente a Klebsiella pneumoniae productora de carbapenemasa y presencia de genes codificantes de bombas de expulsión

Introduction: Acquisition of reduced susceptibility to biocides may contribute to the dissemination of high-risk (HR) clones of carbapenemase-producing Klebsiella pneumoniae (CP-Kp). The aim of this study was (a) to determinate the activity of biocides against CP-Kp, and (b) to analyse the relationship between biocide activity and the presence of efflux pumps. Methods: The minimal inhibitory concentrations (MICs) of 6 biocides (sodium hypochlorite, chlorhexidine digluconate, benzalkonium chloride, povidone-iodine, ethanol and triclosan) were determined in triplicate at 25°C and 37°C in Mueller-Hinton broth (MHB) and M9 minimum medium, against 17 CP-Kp isolates representing different clones (HR and no-HR), sequence-types (STs) and carbapenemases. Efflux pumps genes were detected by whole genome sequencing (MiSeq). Results: Median MICs were slightly higher at 37°C than at 25°C (p≤0.05), except for benzalkonium chloride, triclosan and ethanol. MIC medians were much higher in MHB than in M9, except for triclosan. No significant differences were observed in the median MICs, regarding the type of clone, ST or carbapenemase; cepA, acrAB, kpnEF and oqxAB genes were detected in all isolates, whereas qacE and qacA were not detected; smvAR, and qacΔE genes were detected in 94% and 47% of isolates, respectively. Conclusions: Triclosan, chlorhexidine digluconate, benzalkonium chloride and ethanol were the most active biocides. The activity of some biocides is affected by temperature and growth media, suggesting that standardised procedures for biocide susceptibility testing based on MIC determination are required. This activity, in terms of MICs, are not related to the type of clone, ST, carbapenemase or the presence of the efflux pump genes.(AU)

Introducción: La adquisición de sensibilidad reducida a los biocidas puede contribuir a la diseminación de clones de alto riesgo (HR) de Klebsiella pneumoniae productor de carbapenemasa (Kp-PC). El objetivo de este trabajo fue: (a) determinar la actividad de varios biocidas frente a Kp-PC, y (b) analizar la relación de dicha actividad con la presencia de genes codificantes de bombas de expulsión. Métodos: Las concentraciones mínimas inhibitorias (CMI) de 6 biocidas (hipoclorito de sodio, digluconato de clorhexidina, cloruro de benzalconio, povidona yodada, etanol y triclosán) se determinaron por triplicado a 25 y 37°C, tanto en caldo Mueller-Hinton (MHB) como en medio mínimo M9, frente a 17 aislados de Kp-PC representativos de diferentes clones (HR y no HR), secuenciotipos (ST) y carbapenemasas. Los genes de bombas de expulsión se detectaron mediante secuenciación masiva del genoma completo (MiSeq). Resultados: Las medianas de las CMI fueron ligeramente superiores a 37°C que a 25°C, excepto para cloruro de benzalconio, etanol y triclosán. Las medianas de las CMI fueron considerablemente superiores en MHB que en M9, excepto para triclosán; cepA, acrAB, kpnEF y oqxAB se detectaron en todos los aislados, mientras que qacE y qacA no se detectaron; smvAR y qacΔE se detectaron en el 94% y en el 47% de los aislados, respectivamente. Conclusiones: La actividad de algunos biocidas se afecta por la temperatura y el medio de crecimiento. Esta actividad, en términos de CMI, no se relaciona con el tipo de clon, ST, carbapenemasa, ni con la presencia de genes que codifican bombas de expulsión.(AU)

Síndrome de absceso hepático asociado a colecistitis por Klebsiella pneumoniae hipervirulenta K1 ST23 / Liver abscess syndrome associated with cholecystitis caused by K1 ST 23 hypervirulent Klebsiella pneumoniae

No disponible

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.

Ceftazidime-avibactam: effectiveness and safety in the clinical practice. A third hospital level experience / Ceftazidima-avibactam: efectividad y seguridad en práctica clínica habitual. Experiencia de un hospital de tercer nivel

Objectives: Ceftazidime/avibactam (CZA) is a third generation cephalosporin and the first non-beta-lactam beta-lactamase inhibitor combination. The main outcome was to assess the effectiveness and safety of CZA in the clinical practice.Methods: It was a retrospective observational study. The inclusion criteria were age >18 years and receipt of >24 hours of CZA between January 2016 and October 2018. Variables studied included demographic, clinical, and treatment.Results: 63 inpatients in treatment with CZA were included, 39 (61.9 %) were male and the mean (SD) age was 64.3 (15.8) years. Thirty-eight (60.3%) patients presented bacteremia and 28 (44.4%) were admitted in Intensive Care Unit (ICU). Klebsiella pneumoniae were isolated in 43 (68.3) patients, and OXA-48 carbapenemase in 51 (81.0%). Concomitant antibiotic was used in 40 (63.5%) patients. Mortality at 14 and 30 days were 6 (9.5%) and 4 (6.3%) patients, respectively.Thirty-five (55.6%) patients reached microbiological cure and 47 (74.6%) clinical cure. Infection recurrence evaluated at 90 days was achieved in 23 (36.5%) patients. ICU admission and bacteremia showed decreased in clinical cure (p=0.023 and p=0.01, respectively). Only ICU admission had a diminution in microbiological cure (p=0.035) and bacteremia a higher recurrence evaluated at 90 days (p=0.003). Only 3 (4.8%) patients interrupted treatment because of the adverse events.Conclusions: ICU admission had demonstrated a microbiological and clinical cure decreasing. Recurrence evaluated a 90 days was statically significant higher in patients with bacteremia. CZA was a security antibiotic, with a very low incidence of treatment interruptions. (AU)

Objetivo: Ceftazidima/avibactam (CZA) es una cefalosporina de tercera generación y el primer inhibidor de beta-lactamasas no beta-lactámico. El objetivo principal fue evaluar su efectividad y seguridad en la práctica clínica.Métodos: Se realizó un estudio observacional retrospectivo. Los criterios de inclusión fueron: edad >18 años y administración de >24 horas de CZA entre enero de 2016 y octubre de 2018. Las variables estudiadas incluyeron demograficas, clínicas y de tratamiento.Resultados: Se incluyeron 63 pacientes con CZA, 39 (61,9 %) fueron hombres, media (SD) de edad de 64,3 (15,8) años. 38 (60,3%) pacientes presentaron bacteriemia y 28 (44,4%) fueron ingresados en la Unidad de Cuidados Intensivos (UCI). Klebsiella pneumoniae se aisló en 43 (68,3) pacientes y OXA-48 carbapenemasa en 51 (81,0%). 40 (63,5%) pacientes recibieron antibiótico concomitante. La mortalidad a los 14 y 30 días fue de 6 (9,5%) y 4 (6,3%), respectivamente.Treinta y cinco (55,6%) alcanzaron curación microbiológica y 47 (74,6%) curación clínica. Recurrencia de la infección a los 90 días sucedió en 23 (36,5%). El ingreso en UCI y la bacteriemia demostraron una disminución de la curación clínica (p-0,023 y p-0,01, respectivamente). El ingreso en UCI tuvo una disminución en curación microbiológica (p-0,035) y la bacteriemia en una mayor recurrencia a los 90 días (p-0,003). 3 (4,8%) interrumpieron el tratamiento por toxicidad.Conclusiones: El ingreso en UCI se relacionó con disminución de curación microbiológica y clínica. La recurrencia a los 90 días fue mayor en pacientes con bacteriemia. CZA presenta una incidencia baja de interrupciones del tratamiento. (AU)

Estudio de brote por Klebsiella pneumoniae productor de carbapenemasas OXA-48 + BLEE en pacientes COVID-19 positivos de UCI en el Hospital Universitario HM Puerta del Sur en Móstoles, Madrid / A review of an outbreak of ESBL and OXA 48 carbapenem producing Klebsiella pneumoniae in patients with COVID-19 in the intensive care unit at Hospital HM Puerta del Sur in Móstoles, Madrid

Introducción: El estudio dinámico de brotes por enterobacterias productoras de carbapenemasas (EPC) en pacientes con COVID-19 es uno de los principales temas de investigación epidemiológica actual. Métodos: Estudio descriptivo de un brote por Klebsiella pneumoniae productora de carbapenemasas en el Hospital Universitario HM Puerta del Sur de Madrid. Resultados: El brote afectó a 14 pacientes en UCI en diciembre de 2020, el 57,1%, varones con 65 años de media. El 50% evolucionaron favorablemente y el 50% falleció. En todos se confirmó el mismo clon (cgMLST_579_ST11_HMPS_2020_KPN) de Klebsiella pneumoniae productora de carbapenemasas Clase D-OXA 48 + BLEE CTX-M-15 (KPPC) resistente a cefalosporinas y carbapenems. La duración fue de 92 días. Conclusiones: La vigilancia de la dinámica de los microrganismos resistentes, la implantación de las medidas de prevención y control de la infección en unidades de riesgo y la investigación sobre nuevos tratamientos es fundamental para el avance en su abordaje.(AU)

Introduction: The dynamic study of carbapenem-producing enterobacteriae (CPE) outbreaks in patients with COVID-19 is a major topic for epidemiological research nowadays. Methods: Cross-sectional descriptive study o fan outbreak of carbapenenm-producing Class D-OXA-48 + ESBL at HM Puerta del Sur University Hospital in Madrid. Results: The outbreak involved 14 patients in ICU, in december, 2020, 57,1% of which were male with an average of 65 years. 50% evolved favourably and 50% died. All isolates confirmed having been originated from the same clone of carbapenem-producing Class D-OXA 48 + ESBL CTX-M15 Klebsiella pneumoniae, resistant to cephalosporines and carbapenems. The duration was 92 days. Conclusions: Surveillance of resistant microorganisms dynamics, the implementation of infection prevention and control measures at high risk units and research on new treatments are key to progress in their approach.(AU)

Diseminación interhospitalaria de Klebsiella pneumoniae ST512 productora de KPC-3. Detección por MALDI-TOF / Interhospital dissemination of KPC-3 producing-Klebsiella pneumoniae ST512. Detection by MALDI-TOF

Introducción/Objetivo: Describir un brote por Klebsiella pneumoniae (KPN) productora de KPC-3 y determinar la eficacia diagnóstica de MALDI-TOF en su detección. Métodos: Estudio retrospectivo de las KPN-KPC-3 aisladas en 2 hospitales de Ciudad Real. Se buscó el pico a 11,109kDa±15 en el espectro proporcionado por MALDI-TOF para KPN. Resultados: Se aislaron 156 cepas de KPN que portaban el gen blaKPC-3, con un único perfil perteneciente al ST512 (31 cepas estudiadas). Hubo un 25% de infectados. Un 84% tuvieron origen nosocomial o relacionado con la asistencia sanitaria. El 93% tenía alguna enfermedad de base (31% de exitus en el primer mes). La detección del pico mostró una sensibilidad del 90% y una especificidad del 100%. Conclusiones: Detectamos la diseminación clonal de una cepa de KPN ST512 productora de KPC-3 en 3 hospitales de Ciudad Real. Además, evidenciamos la rentabilidad de MALDI-TOF en la detección precoz de KPN-KPC.(AU)

Introduction/Objective: To describe an outbreak of KPC-3-producing Klebsiella pneumoniae (KPN) and determine the diagnostic efficacy of MALDI-TOF in its detection. Methods: Retrospective study of the KPC-3-KPN isolated in 2 hospitals in Ciudad Real. The peak at 11,109kDa±15 was sought in the KPN spectra provided by MALDI-TOF. Results: We isolated 156 KPN strains that carried the blaKPC-3 gene, with a unique profile belonging to ST512 (31 strains studied). There was 25% of infected patients, 84% were nosocomial or related to health care and 93% had some underlying disease (31% of exitus in the first month). The detection of the peak showed 90% sensitivity and 100% specificity. Conclusions: We detected the clonal spread of a KPN ST512 strain producing KPC-3 in 3 hospitals in Ciudad Real. In addition, we show the profitability of MALDI-TOF in the early detection of KPC-KPN.

Síndrome de abscesos múltiples invasivos en paciente inmunocompetente / Multiple invasive abscesses syndrome in immunocompetent patient

No disponible

Colistina intravesical en el tratamiento de la infección urinaria complicada por Klebsiella pneumoniae BLEE OXA-48 / Intravesical colistin as treatment of complicated urinary infection due to Klebsiella pneumoniae BLEE OXA-48

No disponible