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BACKGROUND: We examined whether the time to positivity (TTP) and growth and detection plot graph (GDPG) created by the automated blood culture system can be used to determine the bacterial load in bacteremic patients and its potential association correlation with disease severity. METHODS: Known bacterial inocula were injected into the blood culture bottles. The GDPGs for the specific inocula were downloaded and plotted. A cohort of 30 consecutive clinical cultures positive for S. aureus and E. coli was identified. Bacterial load was determined by comparing the GDPG with the "standard" curves. Variables associated with disease severity were compared across 3 bacterial load categories (< 100, 100-1000, > 1000 CFU/mL). RESULTS: S. aureus growth was sensitive to the blood volume obtained whereas E. coli growth was less so. A 12-hour delay in sample transfer to the microbiology laboratory resulted in a decrease in TTP by 2-3 h. Mean TTP was 15 and 10 h for S. aureus and E. coli, respectively, which correlates with > 1000 CFU/mL and 500-1000 CFU/ml. For S. aureus, patients with a bacterial load > 100 CFU/mL had a higher mortality rate, (OR for death = 9.7, 95% CI 1.6-59, p = 0.01). Bacterial load > 1000 CFU/mL had an odds ratio of 6.4 (95% CI1.2-35, p = 0.03) to predict an endovascular source. For E. coli bacteremia, we did not find any correlations with disease severity. CONCLUSION: GDPG retrieved from the automated blood culture system can be used to estimate bacterial load. S.aureus bacterial load, but not E.coli, was associated with clinical outcome.
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OBJECTIVES: Bacteroides fragilis is the most frequent cause of anaerobic bacteraemia. Although recent data suggest a rise in antimicrobial resistance (AMR) of this and other anaerobic bacteria, surveillance remains limited due to a lack of both data availability and comparability. However, a newly introduced standardised method for antimicrobial susceptibility testing (AST) of anaerobic bacteria has made larger scale surveillance possible for the first time. The aim of this study was to investigate phenotypic AMR of Bacteroides fragilis isolates from bacteraemia across Europe in 2022. METHODS: In a multicentre approach, clinical microbiology laboratories in Europe were invited to contribute results of AST for Bacteroides fragilis blood culture isolates (including only the first isolate per patient and year). AST of a selection of four antibiotics was performed locally by participating laboratories in a prospective or retrospective manner, using the new EUCAST disc diffusion method on fastidious anaerobe agar (FAA-HB). RESULTS: A total of 16 European countries reported antimicrobial susceptibilities in 449 unique isolates of Bacteroides fragilis from blood cultures in 2022. Clindamycin demonstrated the highest resistance rates (20.9%, range 0 - 63.6%), followed by piperacillin-tazobactam (11.1%, 0-54.5%), meropenem (13.4%, 0-45.5%), and metronidazole (1.8%, 0-20.0%), all with wide variation between countries. CONCLUSION: Considering that the mean resistance rates across Europe were higher than expected for three of the four anti-anaerobic antibiotics under surveillance, both local AST of clinically relevant isolates of Bacteroides fragilis and continued surveillance on an international level is warranted.
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BACKGROUND: Antimicrobial resistance is common in Nocardia species but data regarding the molecular mechanisms beyond their resistance traits are limited. Our study aimed to determine the species distribution, the antimicrobial susceptibility profiles, and investigate the associations between the resistance traits and their genotypic determinants. METHODS: The study included 138 clinical strains of Nocardia from nine Israeli microbiology laboratories. MIC values of 12 antimicrobial agents were determined using broth microdilution. WGS was performed on 129 isolates of the eight predominant species. Bioinformatic analysis included phylogeny and determination of antimicrobial resistance genes and mutations. RESULTS: Among the isolates, Nocardia cyriacigeorgica was the most common species (36%), followed by Nocardia farcinica (16%), Nocardia wallacei (13%), Nocardia abscessus (9%) and Nocardia brasiliensis (8%). Linezolid was active against all isolates, followed by trimethoprim/sulfamethoxazole (93%) and amikacin (91%). Resistance to other antibiotics was species-specific, often associated with the presence of resistance genes or mutations: (1) aph(2â³) in N. farcinica and N. wallacei (resistance to tobramycin); (ii) blaAST-1 in N. cyriacigeorgica and Nocardia neocaledoniensis (resistance to amoxicillin/clavulanate); (iii) blaFAR-1 in N. farcinica (resistance to ceftriaxone); (iv) Ser83Ala substitution in the gyrA gene in four species (resistance to ciprofloxacin); and (v) the 16S rRNA m1A1408 methyltransferase in N. wallacei isolates (correlating with amikacin resistance). CONCLUSIONS: Our study provides a comprehensive understanding of Nocardia species diversity, antibiotic resistance patterns, and the molecular basis of antimicrobial resistance. Resistance appears to follow species-related patterns, suggesting a lesser role for de novo evolution or transmission of antimicrobial resistance.
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Antiinfecciosos , Nocardiosis , Nocardia , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Amicacina , ARN Ribosómico 16S/genética , Nocardiosis/tratamiento farmacológico , Nocardiosis/microbiología , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Bacteriana/genética , Nocardia/genética , Antiinfecciosos/farmacologíaRESUMEN
BACKGROUND: NDM-producing Acinetobacter baumannii (NDMAb) were reported sporadically worldwide but little is known about the transmission, epidemiology and clinical features of NDMAb-infected patients. The goals of this study were to characterize (1) the epidemiology and clinical features of NDMAb-infected patients; (2) the microbiological and molecular features of NDMAb isolates and (3) the transmission networks of NDMAb within healthcare facilities. METHODS: The study was conducted at the Tel-Aviv Sourasky, Rambam and Sha'are-Zedek Medical centers (TASMC, RMC and SZMC, respectively) in Israel. All cases detected between January 2018 and July 2019 were included. Phylogenetic analysis was based on core genome SNP distances. Clonal transmission was defined according to molecular (≤ 5 SNP) and epidemiological criteria (overlapping hospital stay). NDMAb cases were compared at a ratio of 1:2 with non-NDM carbapenem-resistant A. baumannii (CRAb) cases. RESULTS: The study included 54 NDMAb-positive out of 857 CRAb patients, including 6/179 (3.3%) in TASMC, 18/441 (4.0%) in SZMC and 30/237 (12.6%) in RMC. Patients infected by NDMAb had similar clinical features and risk factors as patients with non-NDM CRAb. The length-of-stay was higher in NDMAb cases (48.5 days vs. 36 days, respectively, p = 0.097) and the in-hospital mortality was similarly high in both groups. Most isolates (41/54, 76%) were first detected from surveillance culture. The majority of isolates harbored the blaNDM-2 gene allele (n = 33), followed by the blaNDM-1 (n = 20) allele and the blaNDM-4 allele (n = 1). The majority of isolates were related within the ST level to other isolates in SZMC and RMC: 17/18 and 27/30 isolates, respectfully. The common ST's were the blaNDM-1 harboring ST-2 (n = 3) and ST-107 (n = 8) in SZMC and the blaNDM-2 harboring ST-103 in SZMC (n = 6) and in RMC (n = 27). All blaNDM alleles were located within a conserved mobile genetic environment flanked by the ISAb125 and IS91 family transposon. Clonal transmission was identified in most hospital-acquired cases in RMC and SZMC. CONCLUSION: NDMAb constitutes a minor part of CRAb cases and are clinically similar to non-NDM CRAb. Transmission of NDMAb occurs mostly by clonal spread.
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Acinetobacter baumannii , Humanos , Israel/epidemiología , Acinetobacter baumannii/genética , Filogenia , Alelos , Carbapenémicos/farmacologíaRESUMEN
As a result of the increasing use of sensitive nucleic acid amplification tests, Kingella kingae is being recognized as a common pathogen of early childhood, causing medical conditions ranging from asymptomatic oropharyngeal colonization to bacteremia, osteoarthritis, and life-threatening endocarditis. However, the genomic determinants associated with the different clinical outcomes are unknown. Employing whole-genome sequencing, we studied 125 international K. kingae isolates derived from 23 healthy carriers and 102 patients with invasive infections, including bacteremia (n = 23), osteoarthritis (n = 61), and endocarditis (n = 18). We compared their genomic structures and contents to identify genomic determinants associated with the different clinical conditions. The mean genome size of the strains was 2,024,228 bp, and the pangenome comprised 4,026 predicted genes, of which 1,460 (36.3%) were core genes shared by >99% of the isolates. No single gene discriminated between carried and invasive strains; however, 43 genes were significantly more frequent in invasive isolates, compared to asymptomatically carried organisms, and a few showed a significant differential distribution among isolates from skeletal system infections, bacteremia, and endocarditis. The gene encoding the iron-regulated protein FrpC was uniformly absent in all 18 endocarditis-associated strains but was present in one-third of other invasive isolates. Similar to other members of the Neisseriaceae family, the K. kingae differences in invasiveness and tropism for specific body tissues appear to depend on combinations of multiple virulence-associated determinants that are widely distributed throughout the genome. The potential role of the absence of the FrpC protein in the pathogenesis of endocardial invasion deserves further investigation. IMPORTANCE The wide range of clinical severities exhibited by invasive Kingella kingae infections strongly suggests that isolates differ in their genomic contents, and strains associated with life-threatening endocarditis may harbor distinct genomic determinants that result in cardiac tropism and severe tissue damage. The results of the present study show that no single gene discriminated between asymptomatically carried isolates and invasive strains. However, 43 putative genes were significantly more frequent among invasive isolates than among pharyngeal colonizers. In addition, several genes displayed a significant differential distribution among isolates from bacteremia, skeletal system infections, and endocarditis, suggesting that the virulence and tissue tropism of K. kingae are multifactorial and polygenic, depending on changes in the allele content and genomic organization. Further analysis of these putative genes may identify genomic determinants of the invasiveness of K. kingae and its affinity for specific body tissues and potential targets for a future protective vaccine.
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Bacteriemia , Endocarditis , Kingella kingae , Humanos , Preescolar , Kingella kingae/genética , Virulencia/genética , Factores de Virulencia/genética , Bacteriemia/patologíaRESUMEN
BACKGROUND: Blood culture contamination is associated with health care costs and potential patient harm. Diversion of the initial blood specimen reduces blood culture contamination. We report results of the "real-life" clinical implementation of this technique. METHODS: Following an educational campaign, use of a dedicated diversion tube was recommended prior to all blood cultures. Blood culture sets taken from adults using a diversion tube were defined as "diversion sets," those without, "non-diversion" sets. Blood culture contamination and true positive rates were compared for diversion and nondiversion sets and to nondiversion historical controls. A secondary analysis investigated efficacy of diversion by patient age. RESULTS: Out of 20,107 blood culture sets drawn, the diversion group included 12,774 (60.5%) and the nondiversion group 8,333 (39.5%) sets. The historical control group included 32,472 sets. Comparing nondiversion to diversion, contamination decreased by 31% (5.5% [461/8333] to 3.8% [489/12744], P < .0001]. Contamination was also 12% lower in diversion than historical controls [3.8% (489/12744) vs 4.3% (1,396/33,174) P = .02)]. The rate of true bacteremia was similar. In older patients, contamination rate was higher, and the relative reduction associated with diversion decreased (54.3% amongst 20-40-year-olds vs 14.5% amongst >80-year-olds). CONCLUSIONS: Use of a diversion tube in the ED reduced blood culture contamination in this large real life observational study. Efficacy decreased with increasing age, which requires further investigation.
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Bacteriemia , Recolección de Muestras de Sangre , Adulto , Humanos , Anciano , Cultivo de Sangre/métodos , Mejoramiento de la Calidad , Bacteriemia/prevención & control , Costos de la Atención en Salud , Contaminación de EquiposRESUMEN
OBJECTIVES: NDM-producing Enterobacterales (NDME) account for 34.9% of new carbapenemase-producing Enterobacterales cases in Israeli hospitals. The goals of this study were to characterize the genomic composition of NDME isolates and mobile genetic elements (MGEs) and to identify NDME transmission events (TEs). METHODS: The study was conducted at the Tel-Aviv Sourasky, Rambam and Sha'are-Zedek Medical Centers (TASMC, RMC and SZMC, respectively). All NDME isolates detected between January 2018 and July 2019 were included.Phylogenetic analysis was based on core-genome SNP distances. Core-genome distance of ≤5 SNPs between isolates from patients with overlapping hospitalization periods was suggestive of a potential TE. MGEs were classified by comparison of the blaNDM gene flanking regions. RESULTS: The study included 212 NDME isolates from 203 patients, including 104 isolates from TASMC, 30 isolates from RMC and 78 isolates from SZMC. The majority of isolates (nâ=â157; 74%) harboured the blaNDM-1 gene, followed by the blaNDM-5 (nâ=â48) and blaNDM-15 genes (nâ=â7). The most common NDME species were Klebsiella pneumoniae (nâ=â67), Escherichia coli (nâ=â65) and Enterobacter cloacae (nâ=â45), all showing a highly diverse clonal structure. Most blaNDM-1-harbouring isolates (134/157; 85%) were divided into nine different MGE modules, variably distributed across species and hospitals.The numbers of post-admission acquisition cases (nâ=â118) that could be linked to other cases by both molecular and epidemiological criteria were 13/58 (24.2%), 3/48 (6.3%) and 4/12 (33.3%) in TASMC, SZMC and RMC, respectively. CONCLUSIONS: The study depicted a complex and diverse population structure, suggesting that NDME had not spread via clonal expansion.
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Antibacterianos , beta-Lactamasas , Humanos , Filogenia , Israel/epidemiología , beta-Lactamasas/genética , Proteínas Bacterianas/genética , Hospitales , Klebsiella pneumoniae/genética , Escherichia coli/genética , Pruebas de Sensibilidad Microbiana , PlásmidosRESUMEN
Introduction. Non-typhoidal Salmonella (NTS) bacteremia can cause significant morbidity and mortality. There is high incidence of Salmonellosis in the Middle East, including Israel, but there is a paucity of data on the clinical and epidemiological features of children in comparison to adults.Hypothesis/Gap Statement. Previous studies describing the differences between paediatric and adult populations with Salmonella bacteremia are sparse.Aim. This study's aim was to describe the differences between adults and children with NTS bacteremia.Methodology. All records of patients with NTS bacteremia between 1 January 1998 and 31 July 2020 were reviewed. Data regarding clinical manifestations and laboratory results were extracted from the medical records; records of children (aged <18 years) were compared with those of adults.Results. Records for 137 cases of Salmonella bacteremia (69 adults and 68 children, aged 2 days to 98 years) were reviewed. Seventy nine (58â%) patients had concomitant gastrointestinal symptoms. Fifty-eight (84â%) adults and 13 (19â%) children had underlying conditions (P<0.001). Eighteen patients died, none of whom was a child. Over the study period, most of the children (n=46, 67â%) but only five adults were discharged from the emergency department on their first visit to the ED.Conclusions. The main characteristics of NTS bacteremia in children compared to adults, are higher rates of prior discharge from emergency department, higher rate of gastrointestinal symptoms and better prognosis.
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Bacteriemia , Intoxicación Alimentaria por Salmonella , Infecciones por Salmonella , Fiebre Tifoidea , Adulto , Bacteriemia/epidemiología , Niño , Humanos , Lactante , Salmonella , Infecciones por Salmonella/epidemiologíaRESUMEN
BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) is an important cause of nosocomial infections. Active surveillance for CRAB carriage to identify and isolate colonized patients is used to reduce transmission. OBJECTIVES: To assess the rate and risks of clinical infection among CRAB-carrier and non-carrier patients. METHODS: Hospitalized patients from whom CRAB screening-cultures were obtained between January and June 2018 were identified retrospectively. All CRAB-carriers were compared to a convenient sample of non-carriers and were followed to detect development of CRAB clinical infection during admission. RESULTS: We compared 115 CRAB carriers to 166 non-carriers. The median age in the study group was 76 years (IQR 71-87) vs. 65 years (55-79) in the non-carriers group (P < 0.001). Residence in a nursing facility, debilitated state, and admission to medical wards vs. intensive care units were more frequent among CRAB-carriers (P < 0.001). Mechanically ventilated patients included 51 CRAB carriers (44%) and 102 non-carriers (61%). Clinical infection developed in 49 patients (17%), primarily CRAB pneumonia. Of the CRAB-carriers and non-carriers, 26/115 (23%) and 23/166 (14%), respectively, developed a clinical infection (P = 0.05). One-third of the ventilated patients were infected. Debilitated state and antibiotic treatment during hospitalization were linked to higher infection rates (P = 0.01). Adjusted analysis showed that mechanical ventilation and CRAB colonization were strongly associated with clinical infection (P < 0.05). CONCLUSIONS: The rate of CRAB infection among carriers was high. Mechanical ventilation and CRAB colonization were associated with CRAB clinical infection, primarily pneumonia.
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Infecciones por Acinetobacter , Acinetobacter baumannii , Infección Hospitalaria , Neumonía , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/epidemiología , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Infección Hospitalaria/epidemiología , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana , Neumonía/tratamiento farmacológico , Estudios Retrospectivos , Factores de RiesgoRESUMEN
OBJECTIVE: Environmental surface sampling in healthcare settings is not routinely recommended. There are several methods for environmental surface sampling, however the yield of these methods is not well defined. The aim of the present study is to compare two methods of environmental surface sampling, to characterize the neonatal intensive care unit (NICU) flora, compare it with rates of infection and colonization and correlate it with the workload. DESIGN AND SETTING: First, the yield of the swab and the gauze-pad methods were compared. Then, longitudinal surveillance of environmental surface sampling was performed over 6 months,once weekly, from pre-specified locations in the NICU. Samples were streaked onto selective media and bacterial colonies were identified using matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF). RESULTS: The number of colonies isolated using the gauze pad method was significantly higher compared with the swab method. Overall, 87 bacterial species of 30 different bacterial genera were identified on the NICU environmental surfaces. Of these, 18% species were potential pathogens, and the other represent skin and environmental flora. In 20% of clinical cultures and in 60% of colonization cultures, the pathogen was isolated from the infant's environment as well. The number of bacteria in environmental cultures was negatively correlated with nurse/patient ratio in the day prior to the culture. CONCLUSION: The gauze pad method for environmental sampling is robust and readily available. The NICU flora is very diverse and is closely related with the infants' flora, therefore it may serve as a reservoir for potential pathogens.
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Bacterias/clasificación , Infección Hospitalaria/epidemiología , Monitoreo del Ambiente/métodos , Contaminación de Equipos/estadística & datos numéricos , Bacterias/genética , Bacterias/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Estudios Longitudinales , FilogeniaRESUMEN
Multi-drug-resistant (MDR) Enterobacteriaceae pose a global threat to hospitalized patients. We report a series of colistin-resistant Klebsiella pneumoniae blood isolates from Israel and explore their resistance mechanisms using whole genome sequencing (WGS). Patients with colistin-resistant K. pneumoniae bloodstream infection (BSI) were identified during the period between 2006 and 2018. Demographic and clinical data were collected, and antibiotic susceptibility testing (AST) was performed using three commercial platforms. Long and short read sequencing were performed on a PacBio RS II (Pacific Biosciences) and an Illumina Miseq (Illumina), respectively. Thirteen patients with colistin-resistant K. pneumoniae BSI were identified, and seven isolates from seven different patients were successfully revived. Patient records indicated that five of the patients were previously treated with colistin. AST indicated that six of the seven isolates were colistin resistant and four of these isolates were resistant to carbapenems. WGS assigned the isolates to four distinct clusters that corresponded to in silico-derived multi-locus sequence types (MLST). Three isolates carried blaKPC-3 on two different plasmids and one carried blaOXA-48 on a novel IncL/M plasmid. All colistin-resistant isolates carried a variety of different mutations that inactivated the mgrB gene. We report the first comprehensive analysis of a series of colistin-resistant K. pneumoniae from Israel. A diverse set of isolates were obtained and colistin resistance was found to be attributed to different mechanisms that ablated the mgrB gene. Notably, carbapenemase genes were identified in four isolates and were carried on novel plasmids.
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Bacteriemia , Colistina , Infecciones por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Proteínas Bacterianas/genética , Colistina/farmacología , Colistina/uso terapéutico , Farmacorresistencia Bacteriana/genética , Humanos , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Mutación , Plásmidos/genética , beta-Lactamasas/genéticaRESUMEN
The phylogenetic relatedness of Candida dubliniensis and C. albicans may lead to misidentification of C. dubliniensis and underestimation of its clinical significance. We evaluated the performance of VITEK-MS in identifying C. dubliniensis isolates following growth on different culture media. Correct identification was documented in 98% of the isolates grown on blood agar media whereas only 44% were correctly identified from SDA or CHROMagar. The use of non-manufacturer validated media for identifying C. dubliniensis with VITEK-MS, may result in misidentification of these isolates as C. albicans. This finding calls for reassessing the accuracy of fungal isolates identification in local workflows using non-validated culture media.
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Agar/química , Candida/aislamiento & purificación , Medios de Cultivo/normas , Técnicas de Tipificación Micológica/normas , Sangre , Candida/genética , Candida/crecimiento & desarrollo , Candida albicans/genética , Candida albicans/crecimiento & desarrollo , ADN de Hongos/genética , Humanos , FilogeniaRESUMEN
OBJECTIVES: Nontuberculous mycobacteria (NTM) infections pose a diagnostic challenge in peritoneal dialysis (PD) patients. In this study, we sought to identify findings that are suggestive of NTM infection in PD adult patients. METHODS: All patients with NTM exit-site infection (ESI) with/without tunnel infection and peritonitis identified during the last decade in eight medical centers in Israel were included. Clinical, microbiological, and outcome data were collected and analyzed. RESULTS: Thirty patients were identified; 16 had ESI (53%) and 14 had peritonitis (47%). Median age was 65 years (interquartile range 52-76). Abdominal pain and cloudy PD fluid were reported in all patients with peritonitis, whereas exit-site discharge and granulation tissue were common in patients with ESI. Fourteen patients (47%) had negative cultures prior NTM diagnosis, and isolation of diphtheroids or Corynebacterium spp. was reported in 9 of 30 patients (30%). Antimicrobial treatment prior to diagnosis was documented in 13 of 30 patients (43%). Delayed diagnosis was frequent. Treatment regimens and duration of therapy varied widely. In 26 of 30 (87%) patients, catheter was removed and 19 of 30 patients (63%) required permanent transition to hemodialysis. Two patients with peritonitis (2 of 14, 14%) and seven with ESI (7 of 16, 44%) were eligible for continuation of PD. CONCLUSIONS: Culture negative peritonitis, isolation of diphtheroids or Corynebacterium spp., previous exposure to antibiotics, and/or a refractory infection should all prompt consideration of PD-related NTM infection and timely workup. Catheter removal is recommended aside prolonged antimicrobial therapy. In select patients with ESI, continuation of PD may be feasible.
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Infecciones por Mycobacterium no Tuberculosas , Diálisis Peritoneal , Peritonitis , Adulto , Anciano , Antibacterianos/uso terapéutico , Humanos , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/etiología , Micobacterias no Tuberculosas , Diálisis Peritoneal/efectos adversos , Peritonitis/diagnóstico , Peritonitis/epidemiología , Peritonitis/etiologíaRESUMEN
BACKGROUND: Sinorhizobium meliloti is a phytobacterium found in the root nodules of plants, where it is involved in fixing nitrogen for delivery to the roots in exchange for a photosynthate carbon source. There have been no reported cases of S. meliloti infection in humans. We conducted a retrospective review of clinical records and diagnostic tests. CASE DESCRIPTION: An 81-year-old woman who presented to the emergency department with a 1-day history of progressive decline in her level of consciousness following a head injury and deep scalp laceration. Her medical history was significant for a ventriculoperitoneal shunt due to normal pressure hydrocephalus. Imaging studies revealed hydrocephalus and a tear in the shunt catheter. Cerebrospinal fluid analysis was not suggestive for meningitis. Cerebrospinal fluid culture revealed an unfamiliar organism, identified as S. meliloti following sequencing of its entire genome, which was considered a contaminant. The patient subsequently developed peritonitis, and the same pathogen was detected in the peritoneal fluid, suggesting distal shunt infection. Symptoms resolved after shunt removal and antibiotic treatment. Thorough history taking revealed that the patient had fallen and struck her head against a flowerpot. CONCLUSIONS: S. meliloti is a phytopathogen that should not be easily disregarded as a contaminant when isolated from human sterile fluids or tissues. Aggressive management including removal of infected hardware, if present, is required to ensure resolution of infection. It emphasizes the importance of thorough history taking.
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Infecciones Bacterianas/microbiología , Infecciones por Bacterias Gramnegativas/microbiología , Raíces de Plantas/microbiología , Sinorhizobium meliloti , Anciano de 80 o más Años , Antibacterianos , Líquido Ascítico/microbiología , Infecciones Bacterianas/líquido cefalorraquídeo , Remoción de Dispositivos , Femenino , Infecciones por Bacterias Gramnegativas/líquido cefalorraquídeo , Humanos , Hidrocefalia/complicaciones , Derivación Ventriculoperitoneal/efectos adversosRESUMEN
Our aim was to evaluate the performance of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), routinely used in the microbiology laboratory for bacterial identification, for bacterial typing in the setting of extended spectrum beta-lactamase producing Klebsiella pneumoniae (ESBL-KP) outbreak in the neonatal intensive care unit (NICU). Isolates from a 2011 outbreak in the NICU were retrieved from frozen stocks and analyzed by MALDI-TOF. The MALDI typing was compared with core genome multilocus sequence typing (cg-MLST). MALDI typing divided the 33 outbreak isolates into 2 clones: sequence type (ST)-290 and 405. These results were in complete agreement with cg-MLST results. The differentiation of the outbreak isolates into two clones correlated with the patients' location in the NICU, but also with their place of residence.Conclusion: Here, we show that MALDI-TOF MS, which has been integrated into the microbiology laboratory workflow for microbial species identification, can be secondarily used for epidemiological typing at no added cost. What is Known: ⢠Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is now routinely used in the microbiology laboratory for bacterial identification What is New: ⢠MALDI typing was used for outbreak investigation in the NICU and divided the outbreak isolates into two clones ⢠MALDI-TOF MS may be secondarily used for epidemiological typing at no added cost.
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Unidades de Cuidado Intensivo Neonatal , Infecciones por Klebsiella , Klebsiella pneumoniae , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Brotes de Enfermedades , Humanos , Recién Nacido , Infecciones por Klebsiella/diagnóstico , Klebsiella pneumoniae/genética , Tipificación de Secuencias MultilocusRESUMEN
BACKGROUND: Measures for the prevention of postsurgical infections include issuing special scrubs for the operating room (OR) and prohibiting walking out of the OR complex wearing these scrubs. The aim of this study was to provide further data on bacterial contamination of surgical scrubs. METHODS: Specimens were collected at the entrance to the OR from surgical scrubs worn by surgeons. Participants completed a questionnaire regarding the times, places, and activities in which they were involved during the time interval they were wearing the scrubs. RESULTS: Among the 133 surgeons who participated, the median colony-forming unit (CFU) count was higher (39 CFU/plate) for their scrubs than for clean scrubs worn by the control group (3 CFU/plate; nâ¯=â¯11; P < .001), but there was no significant difference between the study and control groups in the rate of carriage of pathogenic bacteria (13% and 9%, respectively). The majority of the bacteria isolated were considered commensals. Fifty-five (41%) of the surgeons stated that before sampling they took part in medical activities, and 45 (34%) participated in non-medical activities. Practicing these activities was associated with a higher number of CFUs compared to not being involved in such activities (P < .05). CONCLUSIONS: Our data show that, even in less than optimal situations when scrubs are worn outside the OR, surgical scrubs are contaminated with a low bacterial load and only a small number of pathogenic bacteria.
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Bacterias/aislamiento & purificación , Contaminación de Equipos/estadística & datos numéricos , Quirófanos , Vestimenta Quirúrgica/microbiología , Carga Bacteriana/métodos , Humanos , CirujanosRESUMEN
Bacillus cereus isolates causing an outbreak in the neonatal intensive care unit were investigated using whole-genome sequencing. The outbreak coincided with construction work performed adjacent to the neonatal intensive care unit and ceased after strict sealing of the construction area. We found the outbreak to be polyclonal, however, the clonality did not correlate with the virulence in vivo. Genotypically similar isolates were associated with both lethal/severe infection and colonization/environmental contamination. Environmental bacterial load may be a major determinant of infection, especially in high-risk patients. Clinicians should be alert to unusual increase in B. cereus isolations from clinical cultures to facilitate early recognition and investigations of Bacillus outbreaks and pseudo-outbreaks. The integration of genomics into the classical infectious disease work can augment our understanding of pathogen transmission and virulence, and can rapidly assist our response to unusual disease trends.
Asunto(s)
Bacillus cereus/genética , Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Infecciones por Bacterias Grampositivas/epidemiología , Unidades de Cuidado Intensivo Neonatal , Antibacterianos/uso terapéutico , Bacillus cereus/clasificación , Bacteriemia/tratamiento farmacológico , Bacteriemia/epidemiología , Técnicas de Tipificación Bacteriana , Encéfalo/diagnóstico por imagen , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Femenino , Genoma Bacteriano , Genotipo , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Humanos , Recién Nacido , Israel/epidemiología , Tipificación de Secuencias Multilocus , Análisis de Secuencia de ADN , Secuenciación Completa del GenomaRESUMEN
OBJECTIVES: False positive blood cultures result from contamination, consuming laboratory resources and causing unnecessary antibiotic treatment and prolonged hospital stay. Skin disinfection reduces contamination; however, bacteria colonizing human skin are also found in tissues deep into the skin surface. A diversion device diverts the initial 1-2 mL of blood to remove any potentially contaminated skin plug. This study investigates the effect of the device on culture contamination in hospitalized patients. METHODS: In this prospective controlled pragmatic study, blood cultures were obtained using an initial specimen diversion device, either via integrated needle or attachment to a newly placed intravenous catheter. Cultures taken using standard methods served as the control. RESULTS: Six hundred seventy-one blood cultures were obtained. Two hundred seven cultures were taken using an initial specimen diversion device, with 2 (1.0%) contaminated cultures. Four hundred sixty-four cultures were taken without the device, with 24 (5.2%) contaminated cultures (P < .008). No significant difference was shown in the rate of true-positive cultures. CONCLUSIONS: The use of a diversion device was associated with reduced culture contamination in hospitalized patients over a 6-month period, without concomitant reduction in true-positive cultures. This intervention may result in a reduction in costs, antibiotic use, and duration of hospital stay.
Asunto(s)
Cultivo de Sangre , Contaminación de Equipos/prevención & control , Flebotomía/instrumentación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Contaminación de Equipos/estadística & datos numéricos , Reacciones Falso Positivas , Femenino , Humanos , Pacientes Internos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: Following a fatal intensive care unit (ICU) outbreak of carbapenem-resistant Acinetobacter baumanii (CRAB) in 2015, an aggressive infection control intervention was instituted. We outline the intervention and long-term changes in the incidence and prevalence of CRAB. METHODS: The infection control intervention included unit closure (3 days), environmental cleaning, hand hygiene interventions, and environmental culturing. CRAB acquisition and prevalence and colistin use were compared for the 1 year before and 2 years after the intervention. RESULTS: Following the intervention, ICU CRAB acquisition decreased significantly from 54.6 (preintervention) to 1.9 (year 1) to 5.6 cases (year 2)/1000 admissions (p < 0.01 for comparisons with preintervention period.). Unexpectedly, ICU CRAB admission prevalence also decreased from 56.5 to 5.8 to 13 cases/1000 admissions (p < 0.001) despite the infection control intervention's being directed at the ICU alone. In parallel, hospital CRAB prevalence decreased from 4.4 to 2.4 to 2.5 cases/1000 admissions (p < 0.001), possibly as a result of decreased discharge of CRAB carriers from the ICU to the wards (58.5 to 1.9 to 7.4 cases/1000 admissions; p < 0.001). ICU colistin consumption decreased from 200 to 132 to 75 defined daily dose (DDD)/1000 patient-days (p < 0.05). Hospital colistin consumption decreased from 21.2 to 19.4 to 14.1 DDD/1000 patient-days (p < 0.05). CONCLUSIONS: The ICU infection control intervention was highly effective, long-lasting, and associated with a decrease in last-line antibiotic use. The intervention was associated with the unexpected finding that hospital CRAB prevalence also decreased.
Asunto(s)
Infecciones por Acinetobacter/tratamiento farmacológico , Farmacorresistencia Microbiana/efectos de los fármacos , Control de Infecciones/métodos , APACHE , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/patogenicidad , Adulto , Anciano , Anciano de 80 o más Años , Carbapenémicos/administración & dosificación , Carbapenémicos/uso terapéutico , Infección Hospitalaria/etiología , Infección Hospitalaria/prevención & control , Brotes de Enfermedades/prevención & control , Femenino , Humanos , Unidades de Cuidados Intensivos/organización & administración , Unidades de Cuidados Intensivos/estadística & datos numéricos , Israel , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Streptococcus gordonii is an infrequent cause of infective endocarditis (IE); associated spondylodiskitis has not yet been described in the literature. PURPOSE: We describe 2 patients who presented with new-onset, severe back pain; blood cultures revealed S. gordonii bacteremia, which led to the diagnosis of spondylodiskitis and IE. We review our 2-decade experience with S. gordonii bacteremia to describe the clinical and epidemiological characteristics of these patients. RESULTS: In our hospital over the last 20 years (1998-2017), a total of 15 patients with S. gordonii bacteremia were diagnosed, including 11 men and 4 women, and the mean age was 65 ± 22 (range 23-95). The most common diagnosis was IE (9 patients), spondylodiskitis (the presented 2 patients, who in addition were diagnosed with endocarditis), necrotizing fasciitis (1), sternitis (1), septic arthritis (1) and pneumonia (1). The 11 patients with IE were treated with penicillin ± gentamicin, or ceftriaxone for 6 weeks, 5 required valve surgery and 10/11 (91%) attained complete cure. The 2 patients with diskitis required 2-3 months of intravenous antibiotics to achieve complete cure. CONCLUSION: Spondylodiskitis was the presenting symptom of 2/11 (18%) patients with S. gordonii endocarditis. Spondylodiskitis should probably be looked for in patients diagnosed with S. gordonii endocarditis and back pain as duration of antibiotic treatment to achieve complete cure may be considerably longer.