RESUMEN

Bloodstream infection is one of the most important and increasing complications in patients with severe burns. Most of the species affecting this population are Gram-negative bacilli that exhibit antimicrobial resistance. We conducted this study to determine the antimicrobial susceptibility profile and resistance mechanisms of these bacterial infections and their clinical associations on morbidity and mortality. We analyzed a retrospective cohort of burn patients. All patients included in this study had monobacterial blood stream infections during their hospital stay. We performed phenotypic and genotypic tests to determine the antimicrobial resistance mechanism and profile of each strain. Univariate and multivariate logistic regression analysis was performed between variables. We found 109 patients with monobacterial bacteremia. Pseudomonas spp. (50.7%), A. baumannii (46.4%), and Klebsiella spp. (13.8%) were the most common causative microorganisms. The Pseudomonas spp. isolates showed resistance to imipenem (81.5%), mainly by class A and class B carbapenemases. The A. baumannii isolates conferred resistance to imipenem (56.2%), mainly by class D carbapenemases. One quarter of Klebsiella spp. showed resistance to 3rd generation cephalosporins. We also observed that a total body surface area greater than 40% and three or more different types of invasive procedures might be related to increased mortality. Multidrug resistance is highly present. The extent of the burned area and a high number of different types of invasive procedures had an impact in decreasing survivorship in burn patients with bacteremia.

Asunto(s)

Antibacterianos , Bacteriemia , Quemaduras , Humanos , Quemaduras/microbiología , Quemaduras/complicaciones , Masculino , Femenino , Bacteriemia/microbiología , Bacteriemia/tratamiento farmacológico , Persona de Mediana Edad , Adulto , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Estudios Retrospectivos , Pruebas de Sensibilidad Microbiana , Bacterias Gramnegativas/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Anciano , Farmacorresistencia Bacteriana Múltiple , Estudios de Cohortes

RESUMEN

Introduction. Staphylococcus aureus is a leading agent in community-acquired bacteraemia (CAB) and has been linked to elevated mortality rates and methicillin resistance in Costa Rica.Gap statement and aim. To update and enhance previous data obtained in this country, we analysed the clinical manifestations of 54 S. aureus CAB cases in a tertiary hospital and delineated the sequence types (STs), virulome, and resistome of the implicated isolates.Methodology. Clinical information was retrieved from patient files. Antibiotic susceptibility profiles were obtained with disc diffusion and automated phenotypic tests. Genomic data were exploited to type the isolates and for detection of resistance and virulence genes.Results. Primary infections predominantly manifested as bone and joint infections, followed by skin and soft tissue infections. Alarmingly, 70% of patients continued to exhibit positive haemocultures beyond 48 h of treatment modification, with nearly a quarter requiring mechanical ventilation or developing septic shock. The 30-day mortality rate reached an alarming 40%. More than 60% of the patients were found to have received suboptimal or inappropriate antibiotic treatment, and there was an alarming tendency towards the overuse of third-generation cephalosporins as empirical treatment. Laboratory tests indicated elevated creatinine levels, leukocytosis, and bandaemia within the first 24 h of hospitalization. However, most showed improvement after 48 h. The isolates were categorized into 13 STs, with a predominance of representatives from the clonal complexes CC72 (ST72), CC8 (ST8), CC5 (ST5, ST6), and CC1 (ST188). Twenty-four isolates tested positive for mecA, with ST72 strains accounting for 20. In addition, we detected genes conferring acquired resistance to aminoglycosides, MLSB antibiotics, trimethoprim/sulfamethoxazole, and mutations for fluoroquinolone resistance in the isolate collection. Genes associated with biofilm formation, capsule synthesis, and exotoxin production were prevalent, in contrast to the infrequent detection of enterotoxins or exfoliative toxin genes.Conclusions. Our findings broaden our understanding of S. aureus infections in a largely understudied region and can enhance patient management and treatment strategies.

Asunto(s)

Antibacterianos , Bacteriemia , Infecciones Comunitarias Adquiridas , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas , Staphylococcus aureus , Centros de Atención Terciaria , Humanos , Costa Rica/epidemiología , Centros de Atención Terciaria/estadística & datos numéricos , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/mortalidad , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/mortalidad , Bacteriemia/microbiología , Bacteriemia/epidemiología , Bacteriemia/mortalidad , Bacteriemia/tratamiento farmacológico , Masculino , Staphylococcus aureus/genética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Persona de Mediana Edad , Femenino , Anciano , Adulto , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Anciano de 80 o más Años , Adulto Joven , Adolescente , Factores de Virulencia/genética , Niño

RESUMEN

Escherichia coli is a frequent pathogen isolated from bloodstream infections. This study aimed to characterize the genetic features of EC092, an E. coli strain isolated from bacteremia that harbors enteroaggregative E. coli (EAEC) genetic markers, indicating its hybrid pathogenic potential. Whole-genome sequencing showed that EC092 belongs to phylogroup B1, ST278, and serotype O165:H4. Genes encoding virulence factors such as fimbriae, toxins, iron-uptake systems, autotransporter proteins (Pet, Pic, Sat, and SepA), and secretion systems were detected, as well as EAEC virulence genes (aggR, aatA, aaiC, and aap). EC092 was found to be closely related to the other EAEC prototype strains and highly similar in terms of virulence to three EAEC strains isolated from diarrhea. The genomic neighborhood of pet, pic, sat, sepA, and the EAEC virulence genes of EC092 and its three genetically related fecal EAEC strains showed an identical genomic organization and nucleotide sequences. Also, EC092 produced and secreted Pet, Pic, Sat, and SepA in the culture supernatant and resisted the bactericidal activity of normal human serum. Our results demonstrate that the strain EC092, isolated from bacteremia, is a hybrid pathogenic extraintestinal E. coli (ExPEC)/EAEC with virulence features that could mediate both extraintestinal and intestinal infections.

Asunto(s)

Bacteriemia , Infecciones por Escherichia coli , Escherichia coli , Genoma Bacteriano , Factores de Virulencia , Humanos , Bacteriemia/microbiología , Escherichia coli/genética , Escherichia coli/patogenicidad , Factores de Virulencia/genética , Infecciones por Escherichia coli/microbiología , Secuenciación Completa del Genoma , Virulencia/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Filogenia , Genómica/métodos

RESUMEN

PURPOSE OF REVIEW: This review describes the latest information in the management of bloodstream infections caused by multidrug-resistant Gram-negative bacilli (MDRGNB) in critically ill patients. RECENT FINDINGS: The prevalence of bloodstream infections due to MDRGNB is high, and they pose a significant risk in critically ill patients. Recently, novel antimicrobial agents, including new ß-lactam/ß-lactamase inhibitor combinations and cefiderocol, have been introduced for treating these infections. Concurrently, updated guidelines have been issued to aid in treatment decisions. Prompt diagnosis and identification of resistance patterns are crucial for initiating effective antibiotic therapy. Current studies, especially with observational design, and with limited sample sizes and patients with bacteremia, suggest that the use of these new antibiotics is associated with improved outcomes in critically ill patients with MDRGNB bloodstream infections. SUMMARY: For critically ill patients with bloodstream infections caused by MDRGNB, the use of newly developed antibiotics is recommended based on limited observational evidence. Further randomized clinical trials are necessary to determine the most effective antimicrobial therapies among the available options.

Asunto(s)

Antibacterianos , Bacteriemia , Enfermedad Crítica , Farmacorresistencia Bacteriana Múltiple , Infecciones por Bacterias Gramnegativas , Humanos , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Bacterias Gramnegativas/efectos de los fármacos , Unidades de Cuidados Intensivos

Asunto(s)

Infecciones por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli , Infecciones por Klebsiella , Klebsiella pneumoniae , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Humanos , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Klebsiella/microbiología , Proteínas de Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Bacteriemia/microbiología , Masculino

RESUMEN

INTRODUCTION: Delay in initiating appropriate antimicrobial therapy prolongs hospitalization, increases in-hospital mortality, and raises economic costs. Currently, the identification and susceptibility testing of bacteria in positive blood cultures require a considerable amount of time. The objective of this study was to assess the impact of the BCID2 FilmArray® (FA) panel on the timing of appropriate antimicrobial therapy and potential antimicrobial costs. METHODS: This is a retrospective observational study focused on positive blood cultures in hospitalized patients. FA processing was conducted concurrently with routine sample processing. Changes in antibiotic treatments based on FA results were evaluated, and the reduction in antimicrobial therapy duration and associated cost savings were calculated. RESULTS: Eighty-seven bacteremia episodes were analysed. In 42 (48%) of them antimicrobial therapy was de-escalated to narrower spectrum agents, while in 7 (8%) therapy was escalated to broader spectrum antimicrobials. Additionally, in 8 (9%) antimicrobials were switched without changing spectrum and in 30 (34%) no changes were made based on FA results. Antimicrobial changes were made 2.3 days faster than with routine sample processing resulting in calculated potential savings of US$ 7408. CONCLUSION: The implementation of FA facilitated a faster administration of appropriate antimicrobial therapy, leading to a reduction in the duration of broadspectrum empirical antimicrobial therapy and subsequent economic savings.

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Introducción: Los retrasos en el tratamiento antimicrobiano adecuado de las bacteriemias prolongan la estadía hospitalaria, aumentan la mortalidad e incrementan los costos. Aún hoy en día se requiere un tiempo considerable para obtener la identificación y antibiograma de los microorganismos en los hemocultivos positivos. El objetivo fue evaluar el impacto de la implementación del panel BCID2 de FilmArray® (FA) sobre el tiempo de inicio de tratamientos antimicrobianos adecuados y sobre los costos potenciales de los mismos. Métodos: Estudio observacional retrospectivo de los hemocultivos positivos de pacientes hospitalizados, procesados por FA y por metodología tradicional. Se evaluaron los cambios de antimicrobianos en base a los resultados del FA. Se calcularon los días de reducción de tratamiento antimicrobiano y el ahorro potencial en el uso de los mismos, teniendo en cuenta también los costos del FA. Resultados: Se analizaron 87 episodios de bacteriemia. En 42 (48.3%) de ellos se desescaló el tratamiento a antimicrobianos de menor espectro, en 7 (8%) se escaló a antimicrobianos de mayor espectro, en 8 (9.2%) se cambió el antimicrobiano sin variar el espectro y en 30 (34.5%) no se realizaron cambios con los resultados del FA. Los cambios de antimicrobianos se realizaron en promedio 2.3 días más rápido que con los métodos convencionales. Se calculó un ahorro potencial de US$ 7408. Conclusión: La implementación del panel BCID2 de FilmArray® permitió adecuar los tratamientos antimicrobianos más rápidamente acortando la duración de los tratamientos empíricos de amplio espectro, lo cual resultó costo-efectivo.

Asunto(s)

Antibacterianos , Bacteriemia , Humanos , Estudios Retrospectivos , Masculino , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Femenino , Antibacterianos/uso terapéutico , Persona de Mediana Edad , Anciano , Centros de Atención Terciaria , Pruebas de Sensibilidad Microbiana , Sepsis/diagnóstico , Sepsis/tratamiento farmacológico , Sepsis/microbiología , Adulto , Cultivo de Sangre/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/economía , Anciano de 80 o más Años

RESUMEN

Listeria monocytogenes is a Gram-positive aerobic bacterium; found ubiquitously in nature; which mainly affects newborns, older adults, immunosuppressed patients and pregnant women. However, Listeria disease can occur in the healthy population. Invasive listeriosis has three dominant clinical forms, bacteremia, neurolisteriosis and maternal-neonatal infection. Localized forms are infrequently described. The disease occurs mainly secondary to the consumption of contaminated food, including unpasteurized milk or cheese, and occurs in the form of isolated cases or outbreaks, usually beginning a few days after consumption of the contaminated food; although it has been described up to 2 months after ingesting them. There is also the possibility of direct transmission from animals and vertical transmission. Systemic listeriosis without dominant neurological symptoms is a rare event. Two cases are presented. The first was spondylodiscitis in a normal host and the second was Listeria bacteremia in a febrile immunocompromised patient.

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Listeria monocytogenes es una bacteria aeróbica Gram positiva; encontrada enforma ubicua en la naturaleza; que afecta sobre todo a recién nacidos, adultos mayores, pacientes inmunodeprimidos y mujeres embarazadas. Sin embargo, la enfermedad por Listeria puede ocurrir en la población sana. La listeriosis invasiva posee 3 formas clínicas dominantes, bacteriemia, neurolisteriosis e infección materno-neonatal. Las formas localizadas se describen infrecuentemente. La enfermedad se produce fundamentalmente en forma secundaria al consumo de alimentos contaminados, incluidos leche o queso no pasteurizados, y sepresenta en forma de casos aislados o brotes, soliendo comenzar a los pocos días del consumo de éstos; aunque se ha descripto hasta 2 meses después de ingerirlos. También existela posibilidad de transmisión directa desde animales y transmisión vertical. La listeriosis sistémica sin cuadro neurológico dominante es un evento raro. Se presentan dos casos. El primero, una espondilodiscitis en huésped normal y el segundo una bacteriemia por Listeria en un paciente inmunocomprometido febril.

Asunto(s)

Discitis , Listeriosis , Humanos , Listeriosis/diagnóstico , Femenino , Masculino , Discitis/microbiología , Bacteriemia/microbiología , Huésped Inmunocomprometido , Listeria monocytogenes/aislamiento & purificación , Anciano , Persona de Mediana Edad

RESUMEN

PURPOSE: Data on short courses of antibiotic therapy for Enterobacterales bacteremia in high-risk neutropenic patients are limited. The aim of the study was to describe and compare the frequency of bacteremia relapse, 30-day overall and infection-related mortality, Clostridiodes difficile infection and length of hospital stay since bacteremia among those who received antibiotic therapy for 7 or 14 days. METHODS: This is a multicenter, prospective, observational cohort study in adult high-risk neutropenic patients with hematologic malignancies or hematopoietic stem cell transplant and monomicrobial Enterobacterales bacteremia. They received appropriate empirical antibiotic therapy, had a clinical response within 7 days, and infection source control. Clinical, epidemiological and outcomes variables were compared based on 7 or 14 days of AT. RESULTS: Two hundred patients were included (100, 7-day antibiotic therapy; 100, 14-day antibiotic therapy). Escherichia coli was the pathogen most frequently isolated (47.5%), followed by Klebsiella sp. (40.5%). Among those patients that received 7-day vs. 14-day antibiotic course, a clinical source of bacteremia was found in 54% vs. 57% (p = 0.66), multidrug-resistant Enterobacterales isolates in 28% vs. 30% (p = 0.75), and 40% vs. 47% (p = 0.31) received combined empirical antibiotic therapy. Overall mortality was 3% vs. 1% (p = 0.62), in no case related to infection; bacteremia relapse was 7% vs. 2% (p = 0.17), and length of hospital stay since bacteremia had a median of 9 days (IQR: 7-15) vs. 14 days (IQR: 13-22) (p = < 0.001). CONCLUSIONS: These data suggest that seven-day antibiotic therapy might be adequate for patients with high-risk neutropenia and Enterobacterales bacteremia, who receive appropriate empirical therapy, with clinical response and infection source control.

Asunto(s)

Antibacterianos , Bacteriemia , Infecciones por Enterobacteriaceae , Neutropenia , Humanos , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Bacteriemia/mortalidad , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , Neutropenia/complicaciones , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Infecciones por Enterobacteriaceae/mortalidad , Infecciones por Enterobacteriaceae/microbiología , Adulto , Anciano , Enterobacteriaceae/efectos de los fármacos , Resultado del Tratamiento , Tiempo de Internación , Neoplasias Hematológicas/complicaciones , Adulto Joven

RESUMEN

The rapid identification of microorganisms that cause bacteremia and their possible resistance markers are extremely important for the timely initiation of effective antibiotic therapy. The FilmArray® panel BCID2 (an automated rapid multiplex PCR assay) detects microorganisms and resistance genes from positive blood cultures within one hour. The aim of this study was to compare the results obtained from the FilmArray® Panel BCID2 and conventional culture in pediatric patients, as well as the reporting times of both methods. Sixty (60) FilmArray® results were included in the analysis. BCID2 showed high agreement with culture in the identification of microorganisms in monomicrobial bacteremias. However, in polymicrobial blood cultures, BCID2 detected a greater number of microorganisms compared to conventional culture, specifically,1 Staphylococcus aureus, 3 Staphylococcus epidermidis, 1 Enterococcus faecium, 2 Klebsiella oxytoca, 1 Acinetobacter calcoaceticus-baumannii complex, 1 Bacteroides fragilis and 1 Haemophilus influenzae. Furthermore, 88.3% (95%CI: 78.7-94.8) of the FilmArray® results coincided with conventional culture, while in polymicrobial bacteremias, BCID2 detected a greater number of microorganisms with respect to conventional culture [70% (95%CI: 39.3-91.5)]. The agreement of resistance genes was good with a few exceptions (one ESBL was not detected by FilmArray® and one S. aureus strain was characterized as methicillin-resistant by BCID2 and methicillin-sensitive by culture). When comparing the time elapsing since the blood culture was reported as positive up to the results were obtained, BCID2 had a median of 2h 50min (IQR of 1 h 58min to 9h 27min) while the conventional culture had a median of 45h 20min (IQR of 24h 57min to 63h 50min).

Asunto(s)

Bacteriemia , Cultivo de Sangre , Hospitales Pediátricos , Reacción en Cadena de la Polimerasa Multiplex , Humanos , Cultivo de Sangre/métodos , Bacteriemia/microbiología , Bacteriemia/diagnóstico , Reacción en Cadena de la Polimerasa Multiplex/métodos , Niño , Farmacorresistencia Bacteriana/genética , Preescolar , Genes Bacterianos , Lactante , Bacterias/aislamiento & purificación , Bacterias/genética

RESUMEN

Staphylococcus aureus are extremely important microorganisms, either from an epidemiological point of view or as a pathogen, responsible for causing a series of infectious processes, whether simple, restricted to the skin, or invasive infections such as bacteremia. The emergence of Oxacillin Sensitive-Methicillin Resistant S.aureus (OS-MRSA) isolates has imposed difficulties in the treatment of patients with staphylococcal infection, as such isolates can be mistakenly classified as sensitive and lead to failure of the therapy used. Thus, the objective of this study is to evaluate the prevalence, and genotypic and phenotypic characteristics, of OS-MRSA isolates, from bloodstream infections, collected from patients admitted to a hospital in southern Brazil, as well as to evaluate the treatment used. For this, 801 unique isolates of S. aureus, collected from blood cultures, between January 2011 and December 2020 were evaluated. Of these, 96 isolates were classified as sensitive to oxacillin. The isolates were identified and had their sensitivity profile performed by manual and automated methods. The minimum inhibitory concentration for vancomycin, daptomycin, oxacillin, linezolid and teicoplanine was performed by e-test. The mecA, vanA genes, typing of the SCCmec elements, as well as the search for the icaA, tst-1 and pvl virulence genes were performed by PCR. Biofilm formation was performed using the crystal violet technique. The Sequence Type (ST), as well as the Clonal Complex (CC) of the isolates was evaluated by the RTq -PCR. The clinical characteristics of the patients were evaluated through an active search in medical records. After investigating the mecA gene, 27.1% (26/96) of the isolates were considered OS-MRSA, with SCCmec type I being the most prevalent, 46.1% (12/26). Among the evaluated isolates, 41% (9/22) were included in CC5 and ST9. As for virulence, all isolates were positive for the icaA gene and characterized as strong biofilm formers. The pvl gene was found in 92.3% (24/26) of the isolates and the toxic shock syndrome toxin was present in 61.5% of the isolates (16/26). All isolates were negative for the presence of the van A gene. As for the clinical outcome, 73% (19/26) of the patients were discharged from the hospital and 27% (7/26) died. It was possible to observe a high frequency of OS-MRSA isolates causing bloodstream infections. Furthermore, such isolates contain several virulence genes, which may contribute to a worse clinical outcome.

Asunto(s)

Antibacterianos , Bacteriemia , Proteínas Bacterianas , Genotipo , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Oxacilina , Proteínas de Unión a las Penicilinas , Infecciones Estafilocócicas , Centros de Atención Terciaria , Humanos , Oxacilina/farmacología , Brasil , Antibacterianos/farmacología , Infecciones Estafilocócicas/microbiología , Centros de Atención Terciaria/estadística & datos numéricos , Bacteriemia/microbiología , Proteínas Bacterianas/genética , Proteínas de Unión a las Penicilinas/genética , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/clasificación , Fenotipo

RESUMEN

INTRODUCTION: Novel beta-lactam/beta-lactamase inhibitor (BIBLI) combinations are commercially available and have been used for treating carbapenem-resistant Klebsiella pneumoniae (CRKP) infections. Continuous surveillance of susceptibility profiles and resistance mechanism identification are necessary to monitor the evolution of resistance within these agents. OBJECTIVE: The purpose of this study was to evaluate the susceptibility rates of ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam in CRKP isolated from patients with bloodstream infections who underwent screening for a randomized clinical trial in Brazil. METHODS: Minimum inhibitory concentrations (MICs) were determined for meropenem, ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam using the gradient diffusion strip method. Carbapenemase genes were detected by multiplex real-time polymerase chain reaction. Klebsiella pneumoniae carbapenemase (KPC)-producing isolates showing resistance to any BLBLI and New Delhi Metallo-beta-lactamase (NDM)-producing isolates with susceptibility to any BLBLI isolates were further submitted for whole-genome sequencing. RESULTS: From a total of 69 CRKP isolates, 39 were positive for blaKPC, 19 for blaNDM and 11 for blaKPC and blaNDM. KPC-producing isolates demonstrated susceptibility rates above 94 % for all BLBLIs. Two isolates with resistance to meropenem/vaborbactam demonstrated a Gly and Asp duplication at the porin OmpK36 as well as a truncated OmpK35. All NDM-producing isolates, including KPC and NDM coproducers, demonstrated susceptibility rates to ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam of 0 %, 9.1-21.1 % and 9.1-26.3 %, respectively. Five NDM-producing isolates that presented susceptibility to BLBLIs also had porin alterations CONCLUSIONS: This study showed that, although high susceptibility rates to BLBLIs were found, KPC-2 isolates were able to demonstrate resistance probably as a result of porin mutations. Additionally, NDM-1 isolates showed susceptibility to BLBLIs in vitro.

Asunto(s)

Antibacterianos , Compuestos de Azabiciclo , Enterobacteriaceae Resistentes a los Carbapenémicos , Ceftazidima , Combinación de Medicamentos , Infecciones por Klebsiella , Klebsiella pneumoniae , Pruebas de Sensibilidad Microbiana , Inhibidores de beta-Lactamasas , beta-Lactamasas , Humanos , Brasil , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Inhibidores de beta-Lactamasas/farmacología , Infecciones por Klebsiella/microbiología , Compuestos de Azabiciclo/farmacología , Ceftazidima/farmacología , beta-Lactamasas/genética , Antibacterianos/farmacología , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Proteínas Bacterianas/genética , Meropenem/farmacología , Imipenem/farmacología , Bacteriemia/microbiología , Ácidos Borónicos/farmacología , Compuestos Heterocíclicos con 1 Anillo

RESUMEN

INTRODUCTION: Despite improvements in health care, pneumonia-associated mortality remains high. The objective of this study was to analyze the factors associated with mortality in bacteremic pneumonia caused by pneumococcus. METHODS: Retrospective cohort study in adult patients with pneumonia diagnosis and isolation of pneumococcus in blood cultures, between January 2012 and May 2021, was carried out. Clinical and laboratory variables, radiological involvement, evolution and mortality during hospitalization were analyzed. The group of deceased patients was compared with that of survivors. RESULTS: 152 patients were included. Median age: 58 years; men: 58.9%; 33% presented a CURB-65 > than 2 at admission. Overall mortality: 34% (n=52). Deceased patients were more tachypneic on admission (respiratory rate 26 vs. 22; p=0.003), presented sensory alteration more frequently (58% vs. 14%; p< 0.001), PaO2/fraction of inspired oxygen ratio < 250 (58% vs. 22%; p<0.001), bilateral radiological compromise (50% vs. 32%; p=0.03), needed mechanical ventilation (50% vs 12%; p< 0.001), higher blood creatinine values (1.6 vs. 1.15; p=0.01), lower white blood cell count (10 900 vs 17 400; p=0.002), a lower glucose dosage (111 vs. 120; p=0.01), and fewer days of hospital stay (6 vs. 9; p=0.015). In logistic regression model, significant differences were maintained in the following factors associated with mortality: mechanical ventilation (OR=3.54), altered mental status (OR=5.95), chest X-ray with bilateral compromise (OR 3.20) and PAFI less than 250 (OR=3.62). CONCLUSION: In our series, the factors related to mortality, despite the presence of bacteremia, do not differ from those published in the literature and which are part of the different prognostic scores used in routine practice.

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Introducción: A pesar de las mejoras en los cuidados de la salud, la mortalidad asociada a neumonía continúa siendo alta. El objetivo de este estudio fue analizar los factores asociados a mortalidad en neumonía bacteriémica por neumococo. Métodos: Estudio de cohorte retrospectiva en pacientes adultos con diagnóstico de neumonía y neumococo aislado en hemocultivos, entre enero 2012 y mayo 2021. Se analizaron: variables clínicas y de laboratorio, compromiso radiológico, evolución y mortalidad durante la internación. Se comparó el grupo de pacientes fallecidos con el de sobrevivientes. Resultados: Se incluyeron 152 pacientes. La mediana de edad fue de 58 años y el 58.9% fueron hombres. El 33% presentó un CURB-65 mayor a 2 al momento de internación. La mortalidad global fue 34% (n=52). Los pacientes fallecidos se encontraban más frecuentemente taquipneicos al ingreso (frecuencia respiratoria 26 vs. 22; p=0.003), presentaban más frecuentemente alteración del sensorio (58% vs. 14%; p< 0.001), PaO2/fracción inspirada de oxígeno (PAFI) < 250 (58% vs. 22%; p<0.001), compromiso radiológico bilateral (50% vs. 32%; p=0.03), necesidad de asistencia respiratoria mecánica (ARM) (50% vs. 12%; p< 0.001), mayor valor de creatinina en sangre (1.6 vs. 1.15; p=0.01), menor recuento de glóbulos blancos (10 900 vs. 17 400; p=0.002), menor valor de glucemia (111 vs. 120; p=0.01) y menos días de estancia hospitalaria (6 vs. 9; p=0.015). En el análisis de regresión logística multivariable se mantuvieron diferencias significativas en los siguientes factores asociados a mortalidad: ventilación mecánica (OR=3.54), confusión (OR=5.95), radiografía con compromiso bilateral (OR= 3.20) y PAFI < 250 (OR=3.62). Conclusión: Los factores relacionados con mortalidad, a pesar de la presencia de bacteriemia, no difieren de los publicados en la literatura y forman parte de los scores pronósticos de práctica habitual.

Asunto(s)

Neumonía Neumocócica , Humanos , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Femenino , Anciano , Neumonía Neumocócica/mortalidad , Factores de Riesgo , Adulto , Streptococcus pneumoniae , Mortalidad Hospitalaria , Bacteriemia/mortalidad , Bacteriemia/microbiología

RESUMEN

BACKGROUND: CKD patients on hemodialysis (HD) with Staphylococcus aureus (SA) bacteremia present high morbidity, mortality and increased risk of MRSA. Vancomycin is the antibiotic of choice in these cases, it has a narrow therapeutic margin and inadequate dosage generates a risk of toxicity, therefore, the recommendation is to dosage it through serum levels. METHODS: This is a retrospective cohort study in 3 hospitals of third level of complexity in the city of Medellin in which there were differences in the measurement and implementation of vancomycin25 dosage based on trough levels (VL) in patients with chronic kidney disease on hemodialysis (CKD- HD) with uncomplicated bacteremia based infection by methilcillin-resistant Staphyloccocus aureus (MRSA). The primary outcome was the composite of hospital mortality, clinical response (fever, hemodynamic instability and altered consciousness), complications associated with bacteremia, or bacteriological response failure (positive cultures at first week follow-up) at 7 days. The composite variables were analyzed individually as secondary outcomes. RESULTS: The main unadjusted outcome (OR 1.3, CI 0.6 - 2.7) and adjusted for age, Charlson index, loading dose, initial dose, dosing frequency and MIC to vancomycin (OR 1.2, CI 0.5 - 2.7). Regarding adjusted secondary outcomes: clinical response (OR 1.4 CI 0.3 - 5.8), death (OR 1.3 CI 0.3 - 4.6) and complications (OR 0.9, CI 0.37 - 2.2). CONCLUSIONS: We conclude that the measurement of trough levels in patients with HD-CKD does not modify the composite outcome. The main limitation is the sample size and type of study, randomized control trials may be required to confirm the results presented.

Asunto(s)

Antibacterianos , Bacteriemia , Staphylococcus aureus Resistente a Meticilina , Diálisis Renal , Insuficiencia Renal Crónica , Infecciones Estafilocócicas , Vancomicina , Humanos , Vancomicina/uso terapéutico , Estudios Retrospectivos , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Masculino , Diálisis Renal/efectos adversos , Femenino , Insuficiencia Renal Crónica/complicaciones , Anciano , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Persona de Mediana Edad , Antibacterianos/uso terapéutico , Antibacterianos/farmacocinética , Antibacterianos/administración & dosificación , Anciano de 80 o más Años , Pruebas de Sensibilidad Microbiana

RESUMEN

PURPOSE: To evaluate the performance of the rapid colorimetric polymyxin B microelution (RCPEm) in determining polymyxin B resistance directly from Enterobacterales-positive blood cultures. METHODS: A set volume of positive blood culture bottles (diluted 1:10) was inoculated into a glucose-broth-phenol red solution (NP solution), where a polymyxin B disk was previously eluted (final concentration of 3 µg/mL). Test was read each 1 h for up to 4 h. Color change from red/orange to yellow indicated resistant isolates. Results were compared to the reference method, broth microdilution (BMD), performed from colonies grown on solid media from the same blood culture bottle. RESULTS: One hundred fifty-two Enterobacterales-positive blood cultures were evaluated, 22.4% (34/152) of them resistant to polymyxin B (including 6.6% with borderline MICs). When performing directly from positive blood cultures (RCPEm-BC), specificity and sensitivity were 99.1% and 94.1%, respectively. Of note, 79.4% (27/34) of truly resistant isolates required 3 h of incubation, compared to the 18 ± 2 h incubation that microtiter plates of BMD demand before reading can be performed. CONCLUSIONS: RCPEm directly from blood cultures has great potential to be part of the routine of clinical microbiology laboratories to establish polymyxin B susceptibility, impacting outcome of patients with bloodstream infections caused by carbapenem-resistant Enterobacterales.

Asunto(s)

Antibacterianos , Cultivo de Sangre , Colorimetría , Pruebas de Sensibilidad Microbiana , Polimixina B , Polimixina B/farmacología , Humanos , Colorimetría/métodos , Pruebas de Sensibilidad Microbiana/métodos , Antibacterianos/farmacología , Cultivo de Sangre/métodos , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/aislamiento & purificación , Sensibilidad y Especificidad , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/diagnóstico , Farmacorresistencia Bacteriana , Bacteriemia/microbiología , Bacteriemia/diagnóstico

RESUMEN

Bacteremia is a major cause of morbidity and mortality in patients with cancer and episodes of high-risk febrile neutropenia (HRFN). OBJECTIVE: To identify the frequency of microorganisms isolated from blood cultures (BC) and their antimicrobial resistance (R) profile in children with HRFN, compared with the same data from previous studies of the same group. METHOD: Prospective, multicenter, epidemiological surveillance study of microorganisms isolated from BC in patients under 18 years of age, from 7 PINDA network hospitals, between 2016 and 2021. RESULTS: 284 episodes of HRFN with positive BC were analyzed out of 1091 enrolled episodes (26%). Median age 7.2 years [3.0-12.3]. The main isolates were gram-negative bacilli (GNB) 49.2%, gram-positive cocci (GPC) 43.8%, and fungi 3.6%. The most frequently isolated microorganisms were viridans group Streptococci (VGS) (25.8%), Escherichia coli (19.8%), Pseudomonas spp. (11.2%), Klebsiella spp. (10.9%), and coagulase negative Staphylococci (CoNS) (10.9%). There was an increase in R to third-generation cephalosporins (p = 0.011) in GNB and to oxacillin in CoNS (p = 0.00), as well as a decrease in R to amikacin in non-fermenting GNB (p = 0.02) and to penicillin in VGS (p = 0.04). CONCLUSION: VGS is the main agent isolated in BC from pediatric patients with cancer and episodes of HRFN, followed by E. coli, Pseudomonas spp., and Klebsiella spp. Having epidemiological surveillance of microorganisms isolated from BC and their antimicrobial R profile is essential to favor the rational use of antimicrobials.

Asunto(s)

Antibacterianos , Bacteriemia , Cultivo de Sangre , Neutropenia Febril , Neoplasias , Humanos , Niño , Neoplasias/microbiología , Estudios Prospectivos , Preescolar , Neutropenia Febril/microbiología , Neutropenia Febril/tratamiento farmacológico , Chile/epidemiología , Bacteriemia/microbiología , Bacteriemia/epidemiología , Bacteriemia/diagnóstico , Femenino , Masculino , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Pruebas de Sensibilidad Microbiana , Adolescente , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Gramnegativas/efectos de los fármacos

RESUMEN

Klebsiella pneumoniae is an opportunistic pathogen that can colonize the gastrointestinal tract (GIT) of humans. The mechanisms underlying the successful translocation of this pathogen to cause extra-intestinal infections remain unknown, although virulence and antimicrobial resistance traits likely play significant roles in the establishment of infections. We investigated K. pneumoniae strains isolated from GIT colonization (strains Kp_FZcol-1, Kp_FZcol-2 and Kp_FZcro-1) and from a fatal bloodstream infection (strain Kp_HM-1) in a leukemia patient. All strains belonged to ST307, carried a transferable IncF plasmid containing the blaCTX-M-15 gene (pKPN3-307 TypeA-like plasmid) and showed a multidrug-resistance phenotype. Phylogenetic analysis demonstrated that Kp_HM-1 was more closely related to Kp_FZcro-1 than to the other colonizing strains. The Kp_FZcol-2 genome showed 81 % coverage with the Kp_HM-1 246,730 bp plasmid (pKp_HM-1), lacking most of its putative virulence genes. Searching public genomes with similar coverage, we observed the occurrence of this deletion in K. pneumoniae ST307 strains recovered from human colonization and infection in different countries. Our findings suggest that strains lacking the putative virulence genes found in the pKPN3-307 TypeA plasmid are still able to colonize and infect humans, highlighting the need to further investigate the role of these genes for the adaptation of K. pneumoniae ST307 in distinct human body sites.

Asunto(s)

Tracto Gastrointestinal , Infecciones por Klebsiella , Klebsiella pneumoniae , Leucemia , Filogenia , beta-Lactamasas , Humanos , Masculino , Antibacterianos/farmacología , Bacteriemia/microbiología , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Farmacorresistencia Bacteriana Múltiple/genética , Tracto Gastrointestinal/microbiología , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidad , Klebsiella pneumoniae/efectos de los fármacos , Leucemia/microbiología , Leucemia/complicaciones , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Virulencia/genética , Factores de Virulencia/genética , Persona de Mediana Edad

RESUMEN

OBJECTIVES: Ceftazidime-avibactam (CAZ-AVI) is an option for infections caused by MDR gram-negative bacilli. In this study, we aimed to analyze the in vitro antimicrobial activity of CAZ-AVI and other antimicrobial agents against gram-negative bacilli that were collected in Colombia between 2019 and 2021 from patients with bacteremia and skin and soft-tissue infections (SSTIs). METHODS: A total of 600 Enterobacterales and 259 P. aeruginosa strains were analyzed. The phenotypic resistance of isolates, particularly non-susceptibility to meropenem, multidrug-resistant (MDR) isolates, and difficult-to-treat (DTR) P. aeruginosa, was evaluated according to CLSI breakpoints. RESULTS: Enterobacterales had the most susceptibility to CAZ-AVI (96.5 %) and tigecycline (95 %). Tigecycline and CAZ-AVI were the antimicrobial agents with the most in vitro activity against carbapenem-resistant Enterobacterales (CRE). CAZ-AVI was the antimicrobial treatment with the most activity against P. aeruginosa. CONCLUSIONS: Tigecycline and CAZ-AVI were the antimicrobial agents with the most activity against CRE and MDR Enterobacterales. For P. aeruginosa, CAZ-AVI was the antimicrobial treatment with the most in vitro activity.

Asunto(s)

Antibacterianos , Compuestos de Azabiciclo , Bacteriemia , Ceftazidima , Combinación de Medicamentos , Bacterias Gramnegativas , Pruebas de Sensibilidad Microbiana , Infecciones de los Tejidos Blandos , Tigeciclina , Humanos , Ceftazidima/farmacología , Infecciones de los Tejidos Blandos/microbiología , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Colombia , Compuestos de Azabiciclo/farmacología , Antibacterianos/farmacología , Bacteriemia/microbiología , Bacteriemia/tratamiento farmacológico , Bacterias Gramnegativas/efectos de los fármacos , Tigeciclina/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Enterobacteriaceae/efectos de los fármacos , Enfermedades Cutáneas Bacterianas/microbiología , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico

RESUMEN

Our goal was to identify predictors of invasive bacterial infection (ie, bacteremia and bacterial meningitis) in febrile infants aged 2-6 months. In our multicenter retrospective cohort, older age and lower temperature identified infants at low risk for invasive bacterial infection who could safely avoid routine testing.

Asunto(s)

Bacteriemia , Servicio de Urgencia en Hospital , Fiebre , Meningitis Bacterianas , Humanos , Lactante , Estudios Retrospectivos , Masculino , Femenino , Fiebre/etiología , Fiebre/diagnóstico , Meningitis Bacterianas/diagnóstico , Bacteriemia/diagnóstico , Bacteriemia/microbiología , Factores de Riesgo , Infecciones Bacterianas/diagnóstico

RESUMEN

Bacterial bloodstream infections (BSI) are a common threat among patients with haematological malignancies (HM) and hematopoietic stem cell transplant recipients (HSCT). The purpose of this research was to describe clinical and microbiological aspects of BSI caused by carbapenem-resistant Klebsiella pneumoniae (CRKp) and assess risk factors associated with 30-day mortality in a 10-year cohort of haematological patients. A total of 65 CRKp-BSI episodes occurring in HM patients and HSCT recipients and CRKp-BSI between January 2010 and December 2019 were retrospectively studied. Acute leukemias were the most frequently observed underlying disease (87.7%) and 18 patients (27.7%) received HSCT. Mucosal barrier injury in the gastrointestinal tract was the primary cause of bacteremia (86.1%). Also, 14 individuals (21.6%) had an Invasive Fungal Disease (IFD) throughout the episode. Regarding treatment, in 31 patients (47.7%) empirical therapy was deemed appropriate, whereas 33 (50.8%) patients received a combination therapy. Microbiological data revealed that the majority of isolates (53-58%) had the Polymyxin B co-resistance phenotype, while amikacin resistance was less common (16 samples, or 24.7%). The mortality rates at 14 and 30 days were 32.3% and 36.9%, respectively. In a multivariate Cox regression analysis, prompt appropriate antibiotic administration within three days was associated with a better outcome (Adjusted Hazard Ratio [aHR]: 0.33; 95% Confidence Interval [CI]: 0.14-0.76; p = 0.01), whereas hypotension at presentation (aHR: 3.88; 95% CI: 1.40-10.74; p = 0.01) and concurrent IFD (aHR: 2.97; 95% CI: 1.20-7.37; p = 0.02) were independently associated with death within 30 days. Additionally, a favorable correlation between combination therapy and overall survival was found (aHR: 0.18; 95%CI: 0.06-0.56; p = 0.002). In conclusion, 30-day mortality CRKp-BSI was elevated and most of the isolates were polymyxin B resistant. Early appropriate antimicrobial treatment and the use of combination therapy were linked to a better outcome.

Asunto(s)

Bacteriemia , Enterobacteriaceae Resistentes a los Carbapenémicos , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Infecciones por Klebsiella , Humanos , Klebsiella pneumoniae , Estudios Retrospectivos , Polimixina B/uso terapéutico , Brasil/epidemiología , Infecciones por Klebsiella/microbiología , Antibacterianos/uso terapéutico , Bacteriemia/microbiología , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/tratamiento farmacológico , Carbapenémicos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Factores de Riesgo

RESUMEN

INTRODUCCIÓN: Las bacteriemias por Enterobacterales productores de carbapenemasa KPC (EPC-KPC) presentan una mortalidad elevada y opciones terapéuticas limitadas. OBJETIVOS: Describir y comparar la evolución de los pacientes con bacteriemia por EPC-KPC tratados con ceftazidima/avibactam (CA) frente a otros antimicrobianos (OA). PACIENTES Y MÉTODOS: Estudio prospectivo y retrospectivo de casos y controles. Se incluyeron pacientes adultos con bacteriemia por EPC-KPC, con una proporción entre casos tratados con CA y controles tratados con OA. de 1:2. Se analizaron variables clínicas, epidemiológicas y de evolución. RESULTADOS: Se incluyeron 48 pacientes (16 CA y 32 OA). Los casos se encontraban más frecuentemente neutropénicos (50 vs.16%, p = 0,012); asimismo, presentaron medianas de score de APACHE II más altas y de score de Pitt más bajas. El 65% de la cohorte total presentó un foco clínico y Klebsiellapneumoniae fue el microorganismo más frecuentemente aislado. Los casos recibieron una mayor proporción de tratamiento antimicrobiano empírico adecuado (81 vs. 53%, p = 0,05). La antibioterapia dirigida en casos y controles fue combinada en 38 y 91%, p = 0,009. Los casos presentaron menor mortalidad al día 7 y al día 30 relacionada a infección (0 vs. 22%, p = 0,04 y 0 vs. 34%, p = 0,008). Solo los controles desarrollaron shock, ingresaron a la unidad de cuidados intensivos y presentaron bacteriemia de brecha. CONCLUSIÓN: CA mostró beneficio clínico frente a OA para el tratamiento de pacientes con bacteriemia por EPC-KPC.

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BACKGROUND: KPC-producing Enterobacterales bacteremia (KPCCPE) is associated with a high mortality rate and limited therapeutic options. AIM: To describe and compare the outcome of patients with KPC-CPE bacteremia treated with ceftazidime/avibactam (CA) versus other antibiotics (OA). METHODS: Prospective and retrospective cases and control study performed in adult patients with KPC-CPE bacteremia, with a 1:2 ratio between cases treated with CA. and controls treated with OA. Clinical, epidemiological, and outcome variables were analyzed. RESULTS: Forty-eight patients (16 CA and 32 OA) were included. Cases were more frequently neutropenic (50 vs. 16%, p = 0.012), presented higher median APACHE II score and lower Pitt score. Of the total cohort, 65% had a clinical source, and Klebsiella pneumoniae was the most frequently isolated microorganism. Cases received more adequate empirical antibiotic treatment (81 vs. 53%, p = 0.05). Targeted antibiotic therapy in cases and controls was combined in 38 and 91%, p = 0.009. Cases had a lower 7-day mortality and 30-day infection-related mortality (0 vs. 22%, p = 0.04 and 0 vs. 34%, p = 0.008). Only controls developed shock, were admitted to the intensive care unit, and had breakthrough bacteremia. CONCLUSION: CA. showed clinical benefit over OA in the treatment of patients with EPC-KPC bacteremia.

Asunto(s)

Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Ceftazidima/uso terapéutico , Bacteriemia/tratamiento farmacológico , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Compuestos de Azabiciclo/uso terapéutico , Antibacterianos/uso terapéutico , Proteínas Bacterianas , beta-Lactamasas , Estudios de Casos y Controles , Ceftazidima/administración & dosificación , Evolución Clínica , Estudios Prospectivos , Bacteriemia/microbiología , Bacteriemia/mortalidad , Combinación de Medicamentos , Enterobacteriaceae/aislamiento & purificación , Enterobacteriaceae/efectos de los fármacos , Infecciones por Enterobacteriaceae/mortalidad , Compuestos de Azabiciclo/administración & dosificación , Inhibidores de beta-Lactamasas , Antibacterianos/administración & dosificación