Clinical presentation and microbiological characteristics of community-acquired Staphylococcus aureus bacteraemia at a tertiary hospital in Costa Rica.

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.

Cephalotin Versus Dicloxacillin for the Treatment of Methicillin-Susceptible Staphylococcus aureus Bacteraemia: A Retrospective Cohort Study.

BACKGROUND: First-line treatments for methicillin-susceptible S. aureus (MSSA) bacteraemia are nafcillin, oxacillin, or cefazolin. Regional shortages of these antibiotics force clinicians to use other options like dicloxacillin and cephalotin. This study aims to describe and compare the safety and efficacy of cephalotin and dicloxacillin for the treatment of MSSA bacteraemia. METHODS: This retrospective study was conducted in a referral centre in Mexico City. We identified MSSA isolates in blood cultures from 1 January 2012 to 31 December 2022. Patients ≥ 18 years of age, with a first episode of MSSA bacteraemia, who received cephalotin or dicloxacillin as the definitive antibiotic treatment, were included. The primary outcome was in-hospital all-cause mortality. RESULTS: We included 202 patients, of which 48% (97/202) received cephalotin as the definitive therapy and 52% (105/202) received dicloxacillin. In-hospital all-cause mortality was 20.7% (42/202). There were no differences in all-cause in-hospital mortality between patients receiving cephalotin or dicloxacillin (20% vs. 21%, p = 0.43), nor in 30-day all-cause mortality (14% vs. 18%, p = 0.57) or 90-day all-cause mortality (24% vs. 22%, p = 0.82). No severe adverse reactions were associated with either antibiotic. CONCLUSIONS: Cephalotin and dicloxacillin were equally effective for treating MSSA bacteraemia, and both showed an adequate safety profile.

Effect of bloodstream infection on survival in COVID-19 patients admitted to an intensive care unit in Colombia: a matched cohort analysis.

Aim: To determine the impact of bloodstream infection (BSI) and other risk factors for mortality in patients with COVID-19 admitted to the intensive care unit (ICU). Methods: A retrospective cohort was carried out at the Hospital Universitario Nacional (HUN) between March 29 and December 19, 2020. Patients with COVID-19 admitted to the Intensive Care Unit (ICU) were paired 1:4 in two groups, one with BSI and the other without, according to hospital stay and the month of admission. The primary outcome was mortality at 28 days. A Cox proportional hazards model was used to estimate differences in mortality risk. Results: 456 patients were identified and 320 were included in the final cohort, 18% (n = 59) in the BSI group and 82% (n = 261) in the control group. 125 (39%) patients died, 30 (51%) in the BSI group and 95 (36%) in the control group (P = 0.040). BSI was associated with an increased risk of in-hospital mortality at 28 days, [HR] 1.77 (95% CI: 1.03-3.02; P = 0.037). Invasive mechanical ventilation (IMV) and age were associated with increased mortality risk. Some months of the year of the hospital stay were associated with a reduced risk of mortality. There was no difference in mortality between inappropriate and appropriate empirical antimicrobial use. Conclusion: BSI in patients with COVID-19 in ICU increases in-hospital mortality to 28 days. Other risk factors for mortality were IMV and age.

Bacteremia following different oral procedures: Systematic review and meta-analysis.

To evaluate the timing, duration and incidence of bacteremia following invasive dental procedures (IDPs) or activities of daily living (ADL). Eight databases were searched for randomized (RCTs) and nonrandomized controlled trials (nRCTs) evaluating bacteremia before and after IDPs or ADL in healthy individuals. The risk of bias was assessed by RoB 2.0 and ROBINS-I. For the meta-analysis, the primary outcomes were the timing and duration of bacteremia. The secondary outcome was the incidence of bacteremia, measuring the proportion of patients with bacteremia within 5 min after the end of the procedure compared with baseline. We included 64 nRCTs and 25 RCTs. Peak bacteremia occurred within 5 min after the procedure and then decreased over time. Dental extractions showed the highest incidence of bacteremia (62%-66%), followed by scaling and root planing (SRP) (44%-36%) and oral health procedures (OHP) (e.g., dental prophylaxis and dental probing without SRP) (27%-28%). Other ADL (flossing and chewing) (16%) and toothbrushing (8%-26%) resulted in bacteremia as well. The majority of studies had some concerns RCTs or moderate risk of bias nRCTs. Dental extractions, SRP and OHP, are associated with the highest frequency of bacteremia. Toothbrushing, flossing, and chewing also caused bacteremia in lower frequency.

Utilidad del modelo 5MPB-Toledo para predecir bacteriemia en el paciente anciano / Usefulness of the 5MPB-Toledo model to predict bacteremia in the elderly patient

Resumen Objetivo: Analizar la utilidad del modelo predictivo de bacteriemia (5MPB-Toledo) en los mayores de 65 años atendidos por infección en el servicio de urgencias (SU). Material y Método: Estudio observacional prospectivo y multicéntrico de los hemocultivos (HC) obtenidos en pacientes mayores de 65 años atendidos por infección en 66 SU españoles desde el 1 de diciembre de 2019 hasta el 30 de abril de 2020. Se analizó la capacidad predictiva del modelo con el área bajo la curva (ABC) de la característica operativa del receptor (COR) y se calculó el rendimiento diagnóstico de los puntos de corte (PC) del modelo elegido con los cálculos de la sensibilidad, la especificidad, el valor predictivo positivo y el valor predictivo negativo. Resultados: Se incluyeron 2.401 episodios de HC extraídos. De ellos, se consideró como bacteriemia verdadera a 579 (24,11%) y como HC negativo a 1.822 (75,89%). Entre los negativos, 138 (5,74%) se consideraron contaminados. Se categorizó a los pacientes en bajo (0-2 puntos), moderado (3-5 puntos) y alto (6-8 puntos) riesgo, con una probabilidad de bacteriemia de 1,2%, 18,1% y 80,7%, respectivamente. El ABC-COR del modelo tras remuestreo fue de 0,908 (IC 95%: 0,897-0,924). El rendimiento diagnóstico del modelo, considerando un PC ≥ 5 puntos, obtiene una sensibilidad de 94% (IC 95%:92-96), especificidad de 77% (IC 95%:76-79) y un valor predictivo negativo de 97% (IC 95%:96-98). Conclusión: El modelo 5MPB-Toledo es de utilidad para predecir bacteriemia en los mayores de 65 años atendidos en el SU por un episodio de infección.

Abstract Objective: To analyse a risk score to predict bacteremia (MPB5-Toledo) in the patients aged older 65 years seen in the emergency departments (ED) due to infections. Patients and Methods: Prospective and multicenter observational cohort study of the blood cultures (BC) ordered in 66 Spanish ED for patients aged older 65 years seen from December 1, 2019, to April 30, 2020. The predictive ability of the model was analyzed with the area under the Receiver Operating Characteristic curve (AUC-ROC). The prognostic performance for true bacteremia was calculated with the cut-off values chosen for getting the sensitivity, specificity, positive predictive value and negative predictive value. Results: A total of 2.401 blood samples wered cultured. True cases of bacteremia were confirmed in 579 (24.11%). The remaining 1.822 cultures (75.89%) wered negative. And, 138 (5.74%) were judged to be contaminated. Low risk for bacteremia was indicated by a score of 0 to 2 points, intermediate risk by 3 to 5 points, and high risk by 6 to 8 points. Bacteremia in these 3 risk groups was predicted for 1.2%, 18.1%, and 80.7%, respectively. The model´s area under the receiver ope rating characteristic curve was 0.908 (95% CI, 0.897-0.924). The prognostic performance with a model´s cut-off value of ≥ 5 points achieved 94% (95% CI: 92-96) sensitivity, 77% (95% CI: 76-79) specificity, and negative predictive value of 97% (95% CI: 96-98). Conclusion: The 5MPB-Toledo score is useful for predicting bacteremia in the patients aged older 65 years seen in the emergency departments due to infections.

Risk factors and outcomes associated with vancomycin-resistant Enterococcus faecium and ampicillin-resistant Enterococcus faecalis bacteraemia: A 10-year study in a tertiary-care centre in Mexico City.

OBJECTIVES: We sought to identify risk factors associated with vancomycin-resistant Enterococcus faecium (VRE) and ampicillin-resistant Enterococcus faecalis (ARE) bacteraemia, predictors of 30-day mortality, and 90-day recurrence-free survival according to resistance. METHODS: We evaluated clinical records of patients with E. faecalis and E. faecium bacteraemia (2007-2017). We performed bivariate and multivariate logistic regression analyses to identify factors associated with VRE and ARE bacteraemia and predictors of 30-day mortality. A Kaplan-Meier estimate of 90-day recurrence-free survival was done. RESULTS: We identified 192 and 147 E. faecium and E. faecalis bacteraemia episodes, respectively, of which 55.7% of E. faecium were VRE (94% vanA) and 12.2% of E. faecalis were ARE. Factors related to VRE bacteraemia were previous hospitalisation (aOR, 80.18, 95% CI 1.81-634), history of central venous catheter (aOR, 11.15, 95% CI 2.48-50.2) and endotracheal cannula use (aOR, 17.91, 95% CI 1.22-262.82). There was higher attributable mortality to VRE (28%, 95% CI 14-68%; P < 0.001) and ARE (10%, 95% CI 0.1-36%; P = 0.58) compared with their susceptible counterparts. APACHE II (aOR, 1.45, 95% CI 1.26-1.66) and history of chemotherapy (aOR, 3.52, 95% CI 1.09-11.39) were predictors of E. faecium bacteraemia 30-day mortality. We could not recognise any factor related to ARE bacteraemia or E. faecalis 30-day mortality. CONCLUSION: History of hospitalisation and invasive device use were related to VRE bacteraemia. APACHE II and history of chemotherapy were predictors of mortality. We could not identify factors related to ARE or predictors of mortality.

Staphylococcus cohnii endocarditis in native valve.

We present a first case of Staphylococcus cohnii endocarditis in an 80-year-old patient with a history of valve regurgitation. Endocarditis by this organism has not been reported previously. The patient declined treatment and died a few days later. When present, S. cohnii endocarditis has a poor prognosis as a result of associated comorbidities and the infection itself.

Clostridium ramosum rapidly identified by MALDI-TOF MS. A rare gram-variable agent of bacteraemia.

Clostridium ramosum is an enteric anaerobic, endospore-forming, gram-positive rod with a low GC content that is rarely associated with disease in humans. We present a case of C. ramosum bacteraemia. To the best of our knowledge, this is the second case of C. ramosum bacteraemia in an elderly patient presenting with fever, abdominal pain and bilious emesis. We highlight the Gram stain variability, the lack of visualization of spores and the atypical morphology of the colonies that showed C. ramosum in a polymicrobial presentation that initially appeared to show monomicrobial bacteraemia. The microorganism was rapidly identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). We present a comprehensive literature review of 32 cases of clinical infections by C. ramosum in which we describe, if available, sex, age, clinical symptoms, predisposing conditions, other organisms present in the blood culture, other samples with C. ramosum , identification methodology, treatment and outcome.

Outbreaks of severe myositis in cultured white sturgeon (Acipenser transmontanus L.) associated with Streptococcus iniae.

Outbreaks of an infectious disease affecting cultured white sturgeon (Acipenser transmontanus) were investigated. Clinical signs included erratic swimming, arching of the back and mortality. Necropsy findings included poorly demarcated yellow to dark-red and friable lesions in the epaxial muscle, ulcerative skin lesions and haemorrhages in the swim bladder and coelomic wall. Histological evaluation revealed areas of necrotizing and heterophilic myositis with aggregates of bacterial cocci. The lumen of blood vessels in the dermis, under ulcerated areas, and in the posterior kidney, was occluded by fibrin thrombi. Aggregates of Gram-positive cocci were observed in the muscle lesions and within the fibrin thrombi in the dermis and kidney. Genetically homogeneous Streptococcus iniae strains were recovered from affected fish from different outbreaks. The isolates shared high degree of similarity at gene locus (gyrB) with previously characterized S. iniae from cultured fish in California, confirming the emergence of this particular strain of S. iniae in US aquaculture.

Bacteremia in pediatric patients with hematopoietic stem cell transplantation.

BACKGROUND: This study aimed to describe the incidence, microbiological profile, and risk factors associated with bacteremia in pediatric patients with hematopoietic stem cell transplantation (HSCT). METHODS: A retrospective cohort study was performed on patients under 18 years old who underwent HSCT due to any indication, between January 2012 and January 2017. The patient data were collected from the first 100 days post-HSCT. Bacteremia was defined as the isolation of bacteria from at least one blood culture. The relation between bacteremia and associated risk factors was evaluated using univariate and multivariate analysis. RESULTS: We enrolled a total of 111 pediatric patients who received HSCT during the period of study. The total number of patients who developed at least one episode of bacteremia was 46 (41.4%), and the total number of bacteremia episodes was 62. Rectal swabs were performed in 44 patients to detect prior colonization and this showed that 25% of them were positive, the main pathogen isolated being carbapenem-resistant enterobacteriaceae. The Gram-negative bacteria cases accounted for 60% of 62 events. The main Gram-negative bacteria isolated were Klebsiella pneumoniae and Escherichia coli and the majority were resistant strains. The mortality rate on day +100 for the whole cohort was 18% (n=20). Regarding the patients with bacteremia, the mortality rate on day +100 was 30% (n=14), and the cause of death was related to infection in 10 of them. We did not find any statistically significant risk factor for the development of bacteremia. CONCLUSION: Bacteremia is common after HSCT, and there is a high frequency of resistant Gram-negative infections which is related to high mortality.

Predictors of multidrug-resistant Pseudomonas aeruginosa in neutropenic patients with bloodstream infection.

OBJECTIVES: To assess risk factors for multidrug-resistant Pseudomonas aeruginosa (MDR-PA) infection in neutropenic patients. METHODS: Single-centre retrospective analysis of consecutive bloodstream infection (BSI) episodes (2004-2017, Barcelona). Two multivariate regression models were used at BSI diagnosis and P. aeruginosa detection. Significant predictors were used to establish rules for stratifying patients according to MDR-PA BSI risk. RESULTS: Of 661 Gram-negative BSI episodes, 190 (28.7%) were caused by P. aeruginosa (70 MDR-PA). Independent factors associated with MDR-PA among Gram-negative organisms were haematological malignancy (OR 3.30; 95% CI 1.15-9.50), pulmonary source of infection (OR 7.85; 95% CI 3.32-18.56), nosocomial-acquired BSI (OR 3.52; 95% CI 1.74-7.09), previous antipseudomonal cephalosporin (OR 13.66; 95% CI 6.64-28.10) and piperacillin/tazobactam (OR 2.42; 95% CI 1.04-5.63), and BSI occurring during ceftriaxone (OR 4.27; 95% CI 1.15-15.83). Once P. aeruginosa was identified as the BSI aetiological pathogen, nosocomial acquisition (OR 7.13; 95% CI 2.87-17.67), haematological malignancy (OR 3.44; 95% CI 1.07-10.98), previous antipseudomonal cephalosporin (OR 3.82; 95% CI 1.42-10.22) and quinolones (OR 3.97; 95% CI 1.37-11.48), corticosteroids (OR 2.92; 95% CI 1.15-7.40), and BSI occurring during quinolone (OR 4.88; 95% CI 1.58-15.05) and ß-lactam other than ertapenem (OR 4.51; 95% CI 1.45-14.04) were independently associated with MDR-PA. Per regression coefficients, 1 point was assigned to each parameter, except for nosocomial-acquired BSI (3 points). In the second analysis, a score >3 points identified 60 (86.3%) out of 70 individuals with MDR-PA BSI and discarded 100 (84.2%) out of 120 with non-MDR-PA BSI. CONCLUSIONS: A simple score based on demographic and clinical factors allows stratification of individuals with bacteraemia according to their risk of MDR-PA BSI, and may help facilitate the use of rapid MDR-detection tools and improve early antibiotic appropriateness.

Time-kill curves of daptomycin and Monte Carlo simulation for the treatment of bacteraemia caused by Enterococcus faecium.

OBJECTIVES: The aim of this study was to investigate the effect of daptomycin against vancomycin-resistant Enterococcus faecium bacteraemia using computer modelling. METHODS: Data obtained in vitro from time-kill curves were evaluated by PK/PD modelling and Monte Carlo simulations to determine the logarithmic reduction in the number of colony-forming units (CFU)/mL over 18 days of daptomycin treatment at 6, 8, and 10 mg/kg doses every 24 or 48 h and with variations in creatinine clearance (CLCR) of 15-29, 30-49, and 50-100 mL/min/1.73 m2. Monte Carlo simulations were performed to evaluate the probability of target attainment (PTA) for an area under the unbound drug concentration-time curve/minimum inhibitory concentration (fAUC/MIC) > 36 at the same doses and CLCR. RESULTS: Static time-kill model was employed to investigate the antibacterial efficacy of constant daptomycin concentrations. The time-kill curve analysis was performed using mathematical modelling based on a Hill coefficient factor. There was an expressive reduction (> 2 Log CFU/mL) over 18 days of daptomycin treatment in 75th percentile of individuals with CLCR of 15-100 mL/min/1.73 m2) with daptomycin 6-10 mg/kg/day, except for daptomycin every 48 h. Using fAUC/MIC > 36, PTA was > 90% at MICs ≤ 2 µg/mL. CONCLUSIONS: Higher daptomycin doses were associated with higher mortality in time-kill curves. The simulations indicated that independent of the CLCR the therapeutic responses of VRE occur with doses of daptomycin ≥ 6 mg/kg/day and daptomycin every 48 h is insufficient to treat enterococcal bacteraemia.

Bilateral enucleation due to multi-bacterial fulminant endogenous panophthalmitis. / Enucleación bilateral por panoftalmitis endógena polimicrobiana fulminante.

The case is presented of a 62 year-old woman with a rapid, progressive bilateral decrease in visual acuity and panuveitis with orbital cellulitis. She was also in poor general condition, with emesis and fever. Septicaemia due to Klebsiella pneumoniae and bilateral endogenous panophthalmitis were diagnosed. The ocular infection quickly progressed to sclerokeratitis and bilateral perforation despite broad spectrum systemic antibiotic management, and eventually the patient required bilateral enucleation. Microbiological cultures of the surgical pieces identified Klebsiella pneumoniae and Candida magnoliae. To our knowledge, this is the third published case that required bilateral enucleation or evisceration due to endogenous panophthalmitis, and the first case of endogenous ocular infection caused by Candida magnoliae.

High prevalence of B2-ST131 clonal group among extended-spectrum ß-lactamase-producing Escherichia coli isolated from bloodstream infections in Quito, Ecuador.

OBJECTIVES: The purpose of this study was to describe the clonal relationships and phylogroups of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-Ec) isolated from patients with bacteraemia in three hospitals in Quito, Ecuador. METHODS: Between June 2013 and September 2014, a total of 4354 blood cultures were performed in three hospitals located in different areas of Quito. A BACTECTM system was used for blood culture, and the VITEK®2 system was used for species identification and in vitro antimicrobial susceptibility testing. The ESBL genotype, presence of the blaCTX-M, blaTEM and blaSHV genes, and the phylogenetic group of E. coli isolates was determined by PCR. Clonal groups were established by multilocus sequence typing (MLST). RESULTS: Of 929 blood cultures positive for Gram-negative bacilli, 181 (19.5%) were positive for E. coli, representing the most frequent bacteraemia isolates in each hospital. Of the 181 E. coli isolates, 57 (31.5%) were ESBL-Ec. The main sources of ESBL-Ec bacteraemia were urinary tract infection (40; 70.2%), biliary tract infection (10; 17.5%) and other infections (7; 12.3%). The majority of ESBL-Ec isolates (39; 68.4%) from the three hospitals belonged to the virulent phylogenetic group B2, of which 36/39 (92.3%) were ST131 and 33/36 (91.7%) carried the blaCTX-M-15 gene. CONCLUSION: These results provide knowledge of the phylogenetic relationships of E. coli from bacteraemia in Ecuadorian patients. ST131 has emerged in ESBL-Ec, representing an important public-health problem because this multiresistant clone is considered to be a vehicle for the propagation of antimicrobial resistance genes and is a highly virulent, well-adapted human pathogen.

Rates, predictors and mortality of community-onset bloodstream infections due to Pseudomonas aeruginosa: systematic review and meta-analysis.

BACKGROUND: Pseudomonas aeruginosa is mostly a nosocomial pathogen affecting predisposed patients. However, community-onset bloodstream infections (CO-BSI) caused by this organism are not exceptional. OBJECTIVES: To assess the predisposing factors for CO-BSI due to P. aeruginosa (CO-BSI-PA) and the impact in mortality of inappropriate empirical antimicrobial therapy. DATA SOURCE: A systematic literature search was performed in the Medline, Embase, Cochrane Library, Scopus and Web of Science databases. Study eligibility criteria and participants: Articles published between 1 January 2002 and 31 January 2018 reporting at least of 20 adult patients with CO-BSI due to P. aeruginosa were considered. INTERVENTION: Empiric antimicrobial therapy for CO-BSI-PA. METHODS: A systematic review and a meta-analysis were conducted for risk factors and to evaluate if inappropriate empiric antimicrobial therapy increased mortality in CO-BSI-PA using a Mantel-Haenszel effects model. RESULTS: Twelve studies assessing data of 1120 patients were included in the systematic review. Solid tumour (33.1%), haematologic malignancy (26.4%), neutropenia (31.7%) and previous antibiotic use (44.8%) were the most prevalent predisposing factors. Septic shock was present in 42.3% of cases, and 30-day crude mortality was 33.8%. Mortality in meta-analysis (four studies) was associated with septic shock at presentation (odds ratio, 22.31; 95% confidence interval, 3.52-141.35; p 0.001) and with inappropriate empiric antibiotic therapy (odds ratio, 1.83; 95% confidence interval, 1.12-2.98l p 0.02). CONCLUSIONS: CO-BSI-PA mostly occurred in patients with predisposing factors and had a 30-day mortality comparable to hospital-acquired cases. Inappropriate empirical antibiotic therapy was associated with increased mortality. Appropriate identification of patients at risk for CO-BSI-PA is needed for empirical treatment decisions.

Whole-genome analysis and description of an outbreak due to carbapenem-resistant Ochrobactrum anthropi causing pseudo-bacteraemias.

Ochrobactrum anthropi, a rare human pathogen, has been isolated predominantly from patients with catheter-related bacteraemia and rarely from other infections. In 2016, six cases of pseudo-bacteraemia caused by carbapenem-resistant O. anthropi isolates were recovered from an Argentinian hospital. The resistant phenotype exposed by the isolates caught our attention and led to an extensive epidemiologic investigation. Here we describe the characterization of a carbapenem-resistant O. anthropi outbreak whose probable cause was by contaminated collection tubes. The genome analysis of one strain revealed the presence of various resistant determinants. Among them, a metal-dependent hydrolase of the ß-lactamase superfamily I, phnP, was found. Lately the recovery of unusual multidrug-resistant pathogens in the clinical setting has increased, thus emphasizing the need to implement standardized infection control practice and epidemiologic investigation to identify the real cause of hospital outbreaks.

Correct Identification of Ochrobactrum anthropi From Blood Culture Using 16rRNA Sequencing: A First Case Report in an Immunocompromised Patient in Mexico.

The present report describes the misidentification of Brucella spp. from a positive blood culture using traditional microbiology tests. A molecular test identified the bacterium as Ochrobactrum anthropi. According to the information available, this report is the first to include this type of case in Mexico.

First case of bacteraemia due to Acinetobacter schindleri harbouring blaNDM-1 in an immunocompromised patient.

Clinically significant NDM-1-producing Acinetobacter schindleri has not yet been described in the literature. We report the first case of bacteraemia due to an A. schindleri strain harbouring blaNDM-1 recovered from an immunocompromised patient. Our report reinforces the fact that NDM-1 can easily be acquired by Acinetobacter species.

Cuantificación de citoquinas y su relación con la presencia de bacteriemia en leucemias agudas y neutropenia febril postquimioterapia / Quantification of cytokines and their relationship with the presence of bacteraemia in acute leukaemia and febrile neutropenia after chemotherapy

Resumen Objetivo: En pacientes con leucemia aguda y neutropenia febril, describir el comportamiento de varias citoquinas y su relación con la presencia de bacteriemia mediante la medición de interleuquinas1ß， 6, 8,10,12p70 y factor de necrosis tumoral (TNF) en cuatro tiempos. Métodos: Se almacenaron muestras de plasma obtenidas al momento del diagnóstico de la neutropenia, al inicio de la fiebre y a las 24 y 48 horas posteriores, las cuales se conservaron a -70 °C y luego se descongelaron para su procesamiento mediante citometría de flujo. Se utilizaron medianas junto con sus correspondientes medidas de dispersión. Resultados: No hubo ningún reporte de muerte al egreso. La tasa de hemocultivos positivos fue 25% similar a lo revisado en la literatura, con predominio del aislamiento de gérmenes Gram negativos. Las IL10 y 6 mostraron mayor porcentaje de variación durante el momento de la fiebre, comparando el grupo de bacteriémicos con el de no bacteriémicos. Las IL1, IL12p70 y TNFa arrojaron niveles séricos por debajo del límite de detección de la prueba. Conclusiones: Las citoquinas podrían cumplir un papel promisorio en el seguimiento de los pacientes neutropénicos febriles, dada la potencial asociación con presencia de bacteriemia, desenlace bien conocido como predictor de morbilidad y mortalidad en esta población. Sin embargo, se requieren más estudios con mayor población para definir una recomendación.

Abstract Objectives: To describe the properties of several cytokines and their relationship with the presence of bacteraemia by measuring interleukins1ß, 6, 8,10,12p70, and tumour necrosis factor (TNFa) at four different times in patients with acute leukaemia and febrile neutropenia. Methods: Plasma samples were obtained on diagnosis of neutropenia, at the onset of fever, and at 24 hours and 48 hours thereafter. They were stored at -70° C and then thawed for processing by flow cytometry. Medians were used along with their corresponding dispersion measurements. Results: There were no reports of death at discharge. The rate of positive blood cultures was 25%, which was similar to that reviewed in the literature, with predominance of the isolation of Gram negative bacteria. Interleukins 10 and 6 showed a higher percentage of variation during the time of fever on comparing the bacteraemia group with the non- bacteraemia group. IL1, IL12p70, and TNF a 士showed serum levels below the detection limit of the test. Conclusions: Cytokines could play a promising role in the monitoring of febrile neutropenic patients, given the potential association with the presence of bacteraemia, an outcome well known as a predictor of morbidity and mortality in this population. However, more studies with a larger population are required to define a clear recommendation in the management guidelines for febrile neutropenia after chemotherapy.

Influencia en la evolución de los pacientes con bacteriemia/candidemia de la participación activa del especialista clínico en Patología Infecciosa. Estudio de una cohorte prospectiva / The impact of Infectious Disease specialist active care on the outcome of patients with bacteraemia/candidemia. A prospective cohort study María Encarnación Hernández Contrerasa

Introducción: Nuestro objetivo es evaluar el impacto de la participación activa del especialista en Patología Infecciosa en el pronóstico de los enfermos con bacteriemia/candidemia. Pacientes y métodos: Estudio observacional, longitudinal y prospectivo de una cohorte de pacientes con bacteriemia/candidemia en un hospital de tercer nivel (2010-2011). Se analizaron los factores asociados con fracaso terapéutico (persistencia de la bacteriemia/candidemia o muerte relacionada) mediante análisis bivariante y multivariante. Resultados: Se valoraron un total de 324 episodios de bacteriemia/candidemia significativa, de los que en 252 pacientes (78%) el Servicio de Medicina Interna Infecciosas aplicó un sistema de participación activa (recomendación sobre el tratamiento antibiótico). La adquisición de la bacteriemia se consideró nosocomial o relacionada con cuidados sanitarios en 154 pacientes (47,5%) y comunitaria en 170 (52,5%). Los focos de infección más frecuentemente identificados fueron: urinario (31%), catéter vascular (14%), intraabdominal (12%) y desconocido (15%). El 31,6% era portador de sonda vesical y el 35,4%, de catéter venoso central. El 24% de los pacientes no presentaban fiebre (>38 °C) en el momento de cursar los hemocultivos. La bacteriemia fue persistente en 35 pacientes (11%). La mortalidad global fue del 17,4% y del 15% relacionada ("fracaso" terapéutico, 20%). Se asociaron a un mayor fracaso terapéutico el índice de Pitt ≥ 3 (OR 7,94), McCabe III (OR 3,11), uso previo de antibióticos (OR 2,93) y la ausencia de participación activa de los especialistas clínicos en Patología Infecciosa (OR 2,44). Conclusiones: En la cohorte de pacientes con bacteriemia/candidemia estudiada, la gravedad de la enfermedad de base, la gravedad al inicio, el uso previo de antibióticos y la ausencia de participación activa de los especialistas clínicos en Patología Infecciosa se asociaron a fracaso terapéutico.

Introduction: Our objective is to evaluate the impact of active care by an Infectious Diseases specialist (IDS) on the outcome of patients with bacteraemia/candidemia. Patients and methods: Observational, longitudinal and prospective study of a cohort of patients with bacteraemia/candidemia in a tertiary level hospital (2010-2011). Factors associated with treatment failure (persistent bacteraemia or related death) were analysed (bivariate and multivariate analysis). Results: A total of 324 episodes of bacteraemia were included, of which surveillance by IDS was implemented in 252 cases (78%). Acquisition was considered nosocomial or healthcare-related in 154 patients (47.5%) and community acquired in 170 (52.5%). More frequent sources of bacteraemia were urinary tract (31%), vascular catheter (14%), intra-abdominal (12%); and unknown (15%); 31.6% had a urinary catheter and 35.4% had a central venous catheter. When blood cultures were processed, 24% of patients had no fever (> 38 °C). Bacteraemia was persistent in 35 patients (11%). Overall mortality was 17.4% and 15% related (therapeutic "failure", 20%). Failure was associated with Pitt ≥ 3 (OR 7.94), McCabe III (OR 3.11), previous use of antibiotics (OR 2.93) and no active care by IDS (OR 2.44). Conclusions: In our study cohort, severity at presentation, underlying medical conditions, previous antibiotic use and no active Infectious Diseases specialist care were statistically associated with mortality or microbiological failure.