Usefulness of inclusion of ertapenem and temocillin screening breakpoints in the EUCAST rapid antimicrobial susceptibility testing (RAST) for rapid detection of OXA-48-producing Klebsiella pneumoniae directly from positive blood cultures.

OBJECTIVES: The aims of this study were: (i) to assess the ability of the meropenem screening breakpoint as part of the screening rapid antimicrobial susceptibility testing (sRAST) of EUCAST for the detection of OXA-48 carbapenemase-producing Klebsiella pneumoniae directly from positive blood cultures (BCs); and (ii) to evaluate the inclusion of ertapenem and temocillin discs into the sRAST to enhance the detection of OXA-48-producing isolates. METHODS: BC bottles were spiked with a total of 117 K. pneumoniae isolates, including 77 previously characterized OXA-48 producers and 40 non-OXA-48 producers. Disc diffusion assays were directly performed from positive BCs with meropenem (10 µg), ertapenem (10 µg) and temocillin (30 µg) discs, and inhibition zones were manually measured after 4, 6 and 8 h of incubation. The screening cut-off values of sRAST were applied to evaluate their capability in detecting OXA-48-producing isolates. Receiver operating characteristic curves were constructed to illustrate the performance efficacy of the disc diffusion assays to detect OXA-48 producers. RESULTS: The meropenem cut-off values of sRAST only detected 90.91% of the OXA-48-producing isolates after 6 and 8 h of incubation. With the proposed cut-off points for ertapenem [<19 mm (4/6 h) and <20 mm (8 h)] and temocillin [<10 mm (4 h) and <11 mm (6/8 h)], all OXA-48-positive isolates were detected without any false-positive results at any reading time. CONCLUSIONS: In healthcare settings with a high prevalence of OXA-48 producers, the inclusion of ertapenem and temocillin discs in the sRAST procedure may improve the detection of OXA-48-producing K. pneumoniae isolates directly from positive BCs, providing reliable results after only a 4 h incubation period.

Enterococcal Phages: Food and Health Applications.

Enterococcus is a diverse genus of Gram-positive bacteria belonging to the lactic acid bacteria (LAB) group. It is found in many environments, including the human gut and fermented foods. This microbial genus is at a crossroad between its beneficial effects and the concerns regarding its safety. It plays an important role in the production of fermented foods, and some strains have even been proposed as probiotics. However, they have been identified as responsible for the accumulation of toxic compounds-biogenic amines-in foods, and over the last 20 years, they have emerged as important hospital-acquired pathogens through the acquisition of antimicrobial resistance (AMR). In food, there is a need for targeted measures to prevent their growth without disturbing other LAB members that participate in the fermentation process. Furthermore, the increase in AMR has resulted in the need for the development of new therapeutic options to treat AMR enterococcal infections. Bacteriophages have re-emerged in recent years as a precision tool for the control of bacterial populations, including the treatment of AMR microorganism infections, being a promising weapon as new antimicrobials. In this review, we focus on the problems caused by Enterococcus faecium and Enterococcus faecalis in food and health and on the recent advances in the discovery and applications of enterococcus-infecting bacteriophages against these bacteria, with special attention paid to applications against AMR enterococci.

Enterococcus faecium Bacteriophage vB_EfaH_163, a New Member of the Herelleviridae Family, Reduces the Mortality Associated with an E. faecium vanR Clinical Isolate in a Galleria mellonella Animal Model.

The rise of antimicrobial resistant (AMR) bacteria is a major health concern, especially with regard to members of the ESKAPE group, to which vancomycin-resistant (VRE) Enterococcus faecium belongs. Phage therapy has emerged as a novel alternative for the treatment of AMR infections. This, however, relies on the isolation and characterisation of a large collection of phages. This work describes the exploration of human faeces as a source of new E. faecium-infecting phages. Phage vB_EfaH_163 was isolated and characterised at the microbiological, genomic, and functional levels. vB_EfaH_163 phage, a new member of Herelleviridae, subfamily Brockvirinae, has a dsDNA genome of 150,836 bp that does not harbour any virulence factors or antibiotic resistance genes. It infects a wide range of E. faecium strains of different origins, including VRE strains. Interestingly, it can also infect Enterococcus faecalis strains, even some that are linezolid-resistant. Its capacity to control the growth of a clinical VRE isolate was shown in broth culture and in a Galleria mellonella animal model. The discovery and characterisation of vB_EfaH_163 increases the number of phages that might be used therapeutically against AMR bacteria.

Detection of the optrA Gene Among Polyclonal Linezolid-Susceptible Isolates of Enterococcus faecalis Recovered from Community Patients.

Dispersion of transferable oxazolidinone resistance genes among enterococci poses a serious problem to human health. Prompt detection of bacteria carrying these genes is crucial to avoid their spread to multidrug-resistant bacteria. The aim of the study was to describe the presence of optrA-positive isolates among enterococci in a Spanish hospital, and to determine their genetic context and location through whole genome sequencing. All enterococci recovered in a Spanish hospital (Hospital El Bierzo; HEB) from February to December 2018 (n = 443), with minimal inhibitory concentrations (MICs) to linezolid (LZD) ≥4 mg/L, were tested by polymerase chain reaction for the presence of cfr, optrA, and poxtA transferable genes. Only four Enterococcus faecalis isolates (0.9%) had LZD MICs ≥4 mg/L and none of them was positive for cfr or poxtA genes. However, the optrA gene was detected in three isolates collected from urine samples of community patients, whose genomes were sequenced and subjected to bioinformatics analysis. These isolates belonged to different clones: ST7, ST480, and ST585. In these three isolates, the optrA gene was located on plasmids, associated with IS1216 in different arrays. In one isolate, the optrA plasmid coexists with a second plasmid, which carried multiple resistance genes for different classes of antibiotics. Detection of optrA-positive E. faecalis isolates in the community is a matter of concern. The spread of these bacteria into hospital settings, particularly in those, such as the HEB, where vancomycin-resistant enterococci are endemic, should be avoided, to preserve the efficacy of the last-resort oxazolidinones.

Establishment and Persistence of Glycopeptide-Resistant Enterococcus faecium ST80 and ST117 Clones Within a Health Care Facility Located in a Low-Prevalence Geographical Region.

Vancomycin-resistant Enterococcus faecium (VREfm) is one of the most important nosocomial pathogens with limited therapeutic alternatives. In this study, we followed the trends of VREfm and E. faecium causing bloodstream infections (BSIs) in a Spanish hospital, from 2011 to 2020. During this period, 832 E. faecium strains were isolated and 121 (14.5%) were vancomycin resistant. Nineteen of 101 BSIs (18.8%) caused by E. faecium were due to VREfm. The number of BSI-producing E. faecium isolates increased significantly over the past 5 years, with the percentage of invasive VREfm isolates being substantially higher than the average values in Europe and especially in Spain (<3%). VREfm isolates recovered in 2018 (28) and BSI-producing isolates from 2019 (3) and 2020 (2) were molecularly characterized. All were positive for vanA and belonged to sequence type (ST) 80 (28) or ST117 (5), within clonal complex 17. The isolates were only susceptible to linezolid, although most of them were also susceptible (dose dependent) to daptomycin. We report for the first time the establishment and persistence of the VREfm ST80 and ST117 clones in a Spanish hospital. The spread and establishment of hospital-adapted, multidrug-resistant VREfm clones in health care settings are cause for concern and may precede an increment in the BSIs caused by them.

Extensively drug-resistant Acinetobacter baumannii carrying blaOXA-23-like and armA in a hospital after an intervention in the intensive care unit which ended a long-standing endemicity.

The aim of the study was to evaluate for a long time the effectiveness of an intervention designed to reduce carbapenem-resistant Acinetobacter baumannii (CRAB) and its impact on colistin usage in the ICU of a tertiary hospital in Spain. The rate of carbapenem resistance declined drastically during the period of study (2015 to 2018), from 93.57 to 74.65%, especially in the ICU. A significant decrease in colistin usage, from 1.16 to 0.39 DOTs, was observed. Forty-nine CRAB isolates recovered nearly 1 year after starting the intervention were characterized. Most of them were recovered from patients admitted in wards other than ICU and were extensively drug-resistant, carried blaOXA-23-like and armA, and belonged to ST218. Implementation of control measures is crucial to CRAB control in ICUs but must be extended to all wards in order to eradicate CRAB from hospitals.

Linezolid for therapy of Staphylococcus aureus meningitis: a cohort study of 26 patients.

BACKGROUND: Linezolid has good penetration to the meninges and could be an alternative for treatment of Staphylococcus aureus meningitis. We assessed the efficacy and safety of linezolid therapy for this infection. METHODS: Retrospective multicenter cohort study of 26 adults treated with linezolid, derived from a cohort of 350 cases of S. aureus meningitis diagnosed at 11 university hospitals in Spain (1981-2015). RESULTS: There were 15 males (58%) and mean age was 47.3 years. Meningitis was postoperative in 21 (81%) patients. The infection was nosocomial in 23 (88%) cases, and caused by methicillin-resistant S. aureus in 15 cases and methicillin-susceptible S. aureus in 11. Linezolid was given as empirical therapy in 10 cases, as directed therapy in 10, and due to failure of vancomycin in 6. Monotherapy was given to 16 (62%) patients. Median duration of linezolid therapy was 17 days (IQR 12-22 days) with a daily dose of 1,200 mg in all cases. The clinical response rate to linezolid was 69% (18/26) and microbiological response was observed in 14 of 15 cases evaluated (93%). Overall 30-day mortality was 23% and was directly associated with infection in most cases. When compared with the patients of the cohort, no significant difference in mortality was observed between patients receiving linezolid or vancomycin for therapy of methicillin-resistant S. aureus meningitis (9% vs. 20%; p = .16) nor between patients receiving linezolid or cloxacillin for therapy of methicillin-susceptible S. aureus meningitis (20% vs 14%; p = .68). Adverse events appeared in 14% (3/22) of patients, but linezolid was discontinued in only one patient. CONCLUSIONS: Linezolid appears to be effective and safe for therapy of S. aureus meningitis. Our findings showed that linezolid may be considered an adequate alternative to other antimicrobials in meningitis caused by S. aureus.

Pseudomonas aeruginosa nosocomial meningitis in neurosurgical patients with intraventricular catheters: Therapeutic approach and review of the literature / Meningitis nosocomial por Pseudomonas aeruginosa en pacientes portadores de catéteres intraventriculares: aproximación terapéutica y revisión de la literatura

BACKGROUND: Pseudomonas aeruginosa neurosurgical meningitis is a rare entity, usually related with intraventricular catheters and associated with high mortality rates. We describe the clinical characteristics, treatment and outcomes of a series of neurosurgical meningitis caused by P. aeruginosa along 1990-2016. METHODS: Descriptive, retrospective study of all postsurgical meningitis due to P. aeruginosa related to intraventricular catheters in Hospital Universitario Central de Asturias, between 1990 and 2016. Clinical features, therapeutic approaches and prognostic factors were analyzed statistically. A binary logistic regression analysis was performed to determine the factors influencing the infection mortality. RESULT: 51 episodes from 51 different patients with CSF culture positive for P. aeruginosa were reviewed. Seventeen patients (33.3%) died as a direct consequence of the infection. Univariate analysis showed that mortality was higher in the group of patients treated with ceftazidime (12 vs. 15, p = 0.068, OR 3.040 [0.877-10.544]) and lower in patients whom had received intrathecal therapy (2 vs. 13, p = 0.050, OR 4.64 [0.80-34.93]), without differences observed between those patients treated with aminoglycosides or with colistin. Any patient treated with colistin died (0 vs. 6, p = 0.067, OR: not defined). In the multivariate analysis mortality was only significant higher for patients without catheter withdrawal (p = 0.014) and lower for those patients who received intrathecal therapy (p = 0.05) or adequate empirical treatment (p = 0.006). CONCLUSIONS: The mortality of P. aeruginosa meningitis is high especially in infections without catheter withdrawal and in patients for whom the intrathecal route of administration was not used. Catheter withdrawal was an independent factor of good outcome in our series

ANTECEDENTES: La meningitis nosocomial por Pseudomonas aeruginosa es una entidad poco frecuente, generalmente relacionada con catéteres intraventriculares y asociada con altas tasas de mortalidad. Se describen las características clínicas, con especial hincapié en su tratamiento, de una serie de meningitis neuroquirúrgicas por P. aeruginosa entre 1990 y 2016. MÉTODOS: Estudio descriptivo, retrospectivo, de todas las meningitis posquirúrgicas por P. aeruginosa relacionadas con catéteres intraventriculares en el Hospital Universitario Central de Asturias entre 1990 y 2016, con especial hincapié en los enfoques terapéuticos y factores pronósticos. Los factores asociados con mortalidad se analizaron mediante regresión logística binaria. RESULTADOS: Se revisaron 51 episodios de 51 pacientes diferentes con cultivos de LCR positivos para P. aeruginosa. Diecisiete pacientes (33,3%) murieron como consecuencia directa de la infección. La mortalidad fue mayor en el grupo de pacientes tratados con ceftazidima (12 vs. 15, p = 0,068, OR 3,040 [0,877-10,544]) y menor en los pacientes que habían recibido terapia intratecal (2 vs. 13, p = 0,050, OR 4,64 [0,80-34,93]), sin diferencias en estos últimos entre los tratados con aminoglucósidos o con colistina. Ningún paciente tratado con colistina falleció (0 vs. 6, p = 0,067, OR no definida). El análisis multivariable únicamente confirmó la asociación con la ausencia de terapia intratecal (p = 0,05) o tratamiento empírico adecuado (p = 0,006). CONCLUSIONES: La mortalidad de la meningitis por P. aeruginosa es elevada, especialmente en pacientes en quienes no se utilizó la vía de administración intratecal. La retirada del catéter fue un factor independiente de buena evolución en nuestra serie

Pseudomonas aeruginosa nosocomial meningitis in neurosurgical patients with intraventricular catheters: Therapeutic approach and review of the literature.

BACKGROUND: Pseudomonas aeruginosa neurosurgical meningitis is a rare entity, usually related with intraventricular catheters and associated with high mortality rates. We describe the clinical characteristics, treatment and outcomes of a series of neurosurgical meningitis caused by P. aeruginosa along 1990-2016. METHODS: Descriptive, retrospective study of all postsurgical meningitis due to P. aeruginosa related to intraventricular catheters in Hospital Universitario Central de Asturias, between 1990 and 2016. Clinical features, therapeutic approaches and prognostic factors were analyzed statistically. A binary logistic regression analysis was performed to determine the factors influencing the infection mortality. RESULT: 51 episodes from 51 different patients with CSF culture positive for P. aeruginosa were reviewed. Seventeen patients (33.3%) died as a direct consequence of the infection. Univariate analysis showed that mortality was higher in the group of patients treated with ceftazidime (12 vs. 15, p=0.068, OR 3.040 [0.877-10.544]) and lower in patients whom had received intrathecal therapy (2 vs. 13, p=0.050, OR 4.64 [0.80-34.93]), without differences observed between those patients treated with aminoglycosides or with colistin. Any patient treated with colistin died (0 vs. 6, p=0.067, OR: not defined). In the multivariate analysis mortality was only significant higher for patients without catheter withdrawal (p=0.014) and lower for those patients who received intrathecal therapy (p=0.05) or adequate empirical treatment (p=0.006). CONCLUSIONS: The mortality of P. aeruginosa meningitis is high especially in infections without catheter withdrawal and in patients for whom the intrathecal route of administration was not used. Catheter withdrawal was an independent factor of good outcome in our series.

Usefulness of FilmArray Meningitis/Encephalitis panel in the management of an uncommon case of Herpes Simplex Virus type 2 meningitis / Utilidad de la PCR-múltiple (FilmArray Meningitis/Encefalitis) en el manejo de un caso infrecuente de meningitis por Virus Herpes Simple tipo 2

No disponible

Septic arthritis caused by Staphylococcus caprae following arthroscopic meniscus tear repair in a patient without any foreign device / Artritis séptica causada por Staphylococcus caprae tras reparación artroscópica de menisco en paciente sin material protésico

No disponible

Human Pasteurella multocida Infection with Likely Zoonotic Transmission from a Pet Dog, Spain.

We report a case of urinary tract infection caused by an unusual genotype (sequence type 211) of Pasteurella multocida associated with human infection. Molecular genetic analysis of P. multocida isolates obtained from the human patient and his pet strongly suggests a zoonotic transmission of this bacterium.

Evaluation of Sepsis Flow Chip for identification of Gram-negative bacilli and detection of antimicrobial resistance genes directly from positive blood cultures.

Blood stream infections are serious conditions associated with high morbi-mortality. In this study, the new Sepsis Flow Chip (SFC) assay for identification of Gram-negative bacteria and their antimicrobial resistance genes was evaluated in positive blood cultures (BCs). SFC is a microarray with a broad panel comprising the most frequent causative agents of sepsis and antimicrobial resistance genes associated with them. A total of 100 prospective BCs, positive for Gram-negative bacilli, were assessed in the routine of the clinical microbiology laboratory and also applying the SFC assay. Moreover, 19 BCs spiked with well-characterized enterobacterial isolates, harboring antimicrobial resistance genes, were analyzed by the latter. Among the monomicrobial BCs (90), the concordance between SFC identification and the reference method was 94.4%; however, it achieved 100% when SFC was combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry after 4-h incubation. Regarding polymicrobial BCs (10), 15 out of the 22 bacteria present (68.2%) were correctly identified, including all contained in 50% of the cultures. With regard to antimicrobial resistance genes, 98.8%, 98.9%, and 99% concordance was obtained for blaCTX-M, blaOXA-48, and blaVIM, respectively, in comparison with polymerase chain reaction amplification. SFC assay gives results in only 4 h and showed a high concordance rate with the reference method. Although further evaluation studies are necessary, SFC assay implementation, together with antimicrobial stewardship programs, could contribute to improve the therapeutic approaches and to reduce the morbi-mortality, length of hospital stay, and healthcare-associated costs in patients with sepsis.

Vigilancia epidemiológica para microorganismos multirresistentes en una UCI polivalente / Epidemiological surveillance for multidrug-resistant microorganisms in a general ICU

Introducción. Los microorganismos multirresistentes (MMR) suponen una amenaza para los pacientes ingresados en las Unidades de Cuidados Intensivos (UCIs). El objetivo de este estudio es analizar los resultados de los cultivos de vigilancia epidemiológica de dichos microorganismos en una de estas unidades. Material y métodos. UCI polivalente. Análisis retrospectivo, estadística descriptiva. Análisis de cultivos de vigilancia epidemiológica para MMR. Microorganismos estudiados: Staphylococcus aureus resistente a meticilina (SARM), Klebsiella pneumoniae productora de BLEE y/o carbapenemasa (KPBLEE-C) y Acinetobacter baumannii multirresistente (ABMR). Resultados. 1.259 pacientes ingresados. Se analizaron 2.234 muestras (exudado rectal 690, faríngeo 634, nasal 624, cutáneo 286) procedentes de 384 pacientes. La mayor rentabilidad alcanzada con las diferentes muestras para los distintos microorganismos fue: SARM, exudado nasal 79%, nasal + faríngeo 90%. ABMR: faríngeo 80%, faríngeo + rectal 95%. KPBLEE-C: rectal 95%, faríngeo + rectal 98%. De los 384 pacientes 94 (24,4%) estaban colonizados/infectados al ingreso con alguno de estos microorganismos. Durante su estancia, 134 pacientes (10,6% del total de pacientes ingresados) se colonizaron/infectaron por un total de 169 microorganismos. La colonización/infección más precoz fue para SARM (9,2 ± 6,4 días) y la más tardía para enterobacterias productoras de BLEE (18,7±16,4 días). Conclusiones. El 24,4% de los pacientes estaban colonizados/infectados por MMR al ingreso. Las muestras más rentables fueron exudado nasal para SARM, faríngeo para ABMR y rectal para KPBLEE-C. La asociación de dos muestras mejora la detección, excepto en KPBLEE-C. Los exudados cutáneos son poco rentables. El MMR más frecuente al ingreso son las enterobacterias productoras de BLEE y el adquirido intra UCI el ABMR (AU)

Introduction. Multidrug resistant (MDR) microorganisms represent a threat for patients admitted in Intensive Care Units (ICUs). The objective of the present study is to analyse the results of epidemiological surveillance cultures for these microorganisms in one of these units. Material and methods. General ICU. Retrospective analysis, descriptive statistics. Analysis of epidemiological surveillance cultures for MDR microorganisms in 2015. Studied microorganisms: Methicillin-resistant Staphylococcus aureus (MRSA), ESBL-and/or carbapenemase-producing Klebsiella pneumoniae (CESBL-KP) and MDR Acinetobacter baumannii (MDRAB). Results. One thousand, two hundred and fifty nine patients admitted. A total of 2,234 specimens from 384 patients were analysed (690, 634, 62 and 286 were rectal, throat, nasal and skin swabs respectively). Global APACHE II was 18.3 ± 8 versus 21.7 ± 7.8 in patients colonized/infected on admission. Global mortality was 19.7% versus 22.3% in patients colonized/infected on admission. The higher sensitivities achieved with the different samples for the different microorganism detection were as follows. MRSA: 79% and 90% for nasal and nasal + throat swabs, respectively. MDRAB: 80% and 95% for throat and throat + rectal swabs, respectively. CESBL-KP: 95% and 98% for rectal and rectal + throat swabs, respectively. 94 out of the 384 patients (24.4%) were colonized/infected with MDR at admission. 134 patients (10.6% of the total patients admitted) were colonized/infected with a total of 169 MMR during the hospital stay. MRSA has the earliest colonization/ infection (9.2 ± 6.4days) and ESBL-producing Enterobacteriaceae, the latest (18.7± 16.4 days). Conclusions. 24.4% of patients were colonized/infected by MDR at admission. Nasal, throat and rectal swabs were the most effective specimens for recovering MRSA, MDRAB and CESBL-KP, respectively. The combination of two specimens improves MDR detection except for CESBL-KP. Skin swabs are worthless. The most prevalent MDR at admission were ESBL-producing Enterobacteriaceae while the most frequent hospital acquired MDR was MDRAB (AU)

Identification of Enterobacteriaceae and detection of carbapenemases from positive blood cultures by combination of MALDI-TOF MS and Carba NP performed after four hour subculture in Mueller Hinton.

A new protocol for Enterobacteriaceae identification and detection of carbapenemase-producing isolates from blood cultures by combining MALDI-TOF MS and the Carba NP test has been evaluated. Bacterial identification was correct in 129 of the 130 isolates tested while the Carba NP detected 28 out of the 29 carbapenemase producers.