Diseño, estandarización e implementación de una nueva técnica en Guatemala, para el diagnóstico rápido de hemocultivos positivos, utilizando la tecnología Maldi-tof / Design, standardization and implementation of a new technique in Guatemala, for the rapid diagnosis of positive blood cultures, using Maldi-tof technology

Las enfermedades infecciosas son un problema de salud que a pesar de los avances médicos siguen cobrando vi-das en todo el mundo; como las septicemias. La presente investigación tuvo por objetivo diseñar, estandarizar e implementar un protocolo inexistente en Guatemala, para el diagnóstico rutinario de hemocultivos positivos dentro de las instalaciones del Laboratorio Clínico del Hospital General San Juan de Dios, lugar en donde se encuentra el único espectrómetro de masas de tipo Maldi-tof (Matrix Assisted Laser Desorption Ionization-Time of flight-mass spectrometry).Se utilizaron 240 muestras de pacientes de los diferentes servicios. El diagnóstico se realizó compa-rando las identificaciones obtenidas a partir de cultivos microbiológicos puros con muestras directas de botellas con caldo BHI(Brain Heart Infusion).Los resultados de las dos metodologías fueron evaluados con el diseño estadístico "apareado o emparejado en grupo". La comparación no evidenció discordancia en las identificaciones; pero sí en los tiempos de respuesta. La reducción de tiempo fue de 42.9 h para bacterias Gram positivo, 45.0 h para bacterias Gram negativo y 126.2 h para levaduras, todos a favor de identificaciones a partir de muestras directas. Con esta investigación se pretende ofrecer una nueva alternativa que permitirá brindar un diagnóstico rápido, confiable y certero a la población guatemalteca. También permitirá reducir la morbimortalidad de los pacientes con septicemias, promover el ahorro de insumos hospitalarios, disminuir el tiempo de estancia hospitalaria, ahorrar el consumo de antibióticos innecesarios y contribuir indirectamente a combatir la resistencia antimicrobiana; un problema actual de gran importancia a nivel mundial.

Infectious diseases are a health problem that despite medical advances in terms of diagnosis continue to take lives worldwide, such is the case of sepsis. The purpose of this research was to design, standardize and implement a non-existent protocol in Guatemala, for the routine diagnosis of positive blood cultures, within the facilities of the clinical laboratory of the San Juan de Dios General Hospital; where the only Maldi-tof (Matrix Assisted Laser Desorp-tion Ionization-Time of flight-mass spectrometry) type mass spectrometer is located. For this, 240 samples of positive blood cultures were used, coming from patients of the different services. The microbiological diagnosis was made by comparing the identification data obtained from pure microbiological cultures and direct samples of BHI broth (Brain Heart Infusion) bottles. The results of the two methodologies were evaluated based on "paired or matched in groups" statistical design. The Maldi-tof technique did not show disagreement regarding identification between the two types of samples; but it did in the response time. The time reduction was 42.9 h for Gram positive bacteria, 45.0 h for Gram negative and 126.2 h for yeasts, supporting identification from direct samples. This research aims to provide a new diagnostic alternative that will allow access to fast, reliable, and accurate results for the Guatemalan population. It will also help to reduce e morbidity and mortality rates of patients with sepsis, to promote hospital supplies savings, decrease the patient length of stay, save unnecessary antibiotics and indirectly contribute to combating antimicrobial resistance; a critical problem faced by the world today.

Epidemiología y patrones de sensibilidad a los antimicrobianos de microorganismos aislados de hemocultivos en niños con leucemia aguda / Epidemiology and sensitivity patterns of antimicrobials in microorganisms isolated in blood cultures of children with acute leukemia

Las infecciones bacterianas son una de las principales causas de morbimortalidad en los niños con cáncer. Nuestro objetivo fue describir y comparar las características clínicas y los microorganismos causantes de bacteriemias con su sensibilidad antimicrobiana en niños con diagnóstico de LLA y LMA. Se realizó un estudio observacional, descriptivo entre julio-2016 y junio-2018. Se incluyeron todos los episodios de bacteriemia (EpB) en pacientes de 0 a 18 años con diagnóstico de LLA y LMA. Se documentaron datos epidemiológicos y demográficos de los pacientes y datos microbiológicos de los aislamientos de hemocultivos positivos. Se utilizó stata13. Se incluyeron 258 EpB en 167 pacientes; el 55% eran varones. La mediana de edad fue 81 meses (RIC 39-130). En 215 EpB (83%) se registró la presencia de algún tipo de catéter; neutropenia en 193 EpB (75%), neutropenia severa en 98/258 EpB (38%). Se pudo determinar el foco clínico en 152 EpB (59%). Ciento diez pacientes tenían LLA y 57 LMA. En LLA predominaron las enterobacterias, en LMA los cocos gram positivos. Se observó asociación entre LMA y estreptococos del grupo Viridans (p<0,01) y entre LLA y P.aeruginosa (p 0,01). Con respecto a la sensibilidad hubo 11% y 17% de bacilos negativos multirresistentes en LLA y LMA respectivamente. Todos los estafilococos coagulasa negativos fueron meticilino resistentes. La mayoría de los pacientes tenía algún tipo de catéter y neutropenia. Se observó un predominio de enterobacterias con bajos niveles de resistencia antibiótica. Estos resultados son importantes para conocer la epidemiología local y establecer tratamientos empíricos adecuados (AU)

Bacterial infections are one of the main causes of morbidity and mortality in children with cancer. Our aim was to describe and compare the clinical features and bacteremia-causing microorganisms together with their antimicrobial sensitivity in acute lymphocytic (ALL) and acute myelocytic leukemia (AML). A descriptive observational study was conducted between July 2016 and June 2018. All episodes of bacteremia (EpB) in patients between 0 and 18 years of age with ALL and AML were included. All epidemiological and demographic data of the patients and microbiological information of the isolates of the positive blood cultures were recorded. For statistical analysis stata13 was used. Overall 258 EpB in 167 patients were included; 55% were boys. Median age was 81 months (IQR 39-130). In 215 EpB (83%) some type of catheter was involved; neutropenia was observed in 193 EpB (75%) and severe neutropenia in 98/258 EpB (38%). A clinical focus could be determined in 152 EpB (59%). Of all patients, 110 had ALL and 57 AML. The predominant micro-organisms were enterobacteria in ALL and gram-positive cocci in AML. An association was observed between AML and the viridans group of streptococci (p<0.01) and between ALL and P. aeruginosa (p 0.01). Regarding sensitivity, there were 11% and 17% of multiresistant negative bacilli in ALL and AML, respectively. All coagulase-negative staphylococci weer methicillin resistant. The majority of patients had some type of catheter and neutropenia. Predominance of enterobacteria with low levels of resistance to antibiotics was observed. These results are important to understand the local epidemiology and establish adequate empirical therapies (AU)

Infections and antimicrobial resistance in an adult intensive care unit in a Brazilian hospital and the influence of drug resistance on the thirty-day mortality among patients with bloodstream infections

Abstract INTRODUCTION: The present study aimed to determine the incidence of health care-associated infections (HCAIs) and identify the main resistant microorganisms in intensive care unit (ICU) patients in a Brazilian university hospital. METHODS: A retrospective cohort study was conducted in a Brazilian teaching hospital between 2012 and 2014. RESULTS: Overall, 81.2% of the infections were acquired in the ICU. The most common resistant pathogenic phenotypes in all-site and bloodstream infections were oxacillin-resistant coagulase-negative staphylococci and carbapenem-resistant Acinetobacter spp. (89.9% and 87.4%; 80.6% and 70.0%), respectively. CONCLUSIONS: There is an urgent need to focus on HCAIs in ICUs in Brazil.

Microbiologic characteristics and antibiotic resistance rates of diabetic foot infections / Perfil microbiológico e de resistência bacteriana no pé diabético infectado

ABSTRACT Purpose: the purpose of this research was to identify the sociodemographic and microbiological characteristics and antibiotic resistance rates of patients with diabetic foot infections, hospitalized in an emergency reference center. Methods: it was an observational and transversal study. The sociodemographic data were collected by direct interview with the patients. During the surgical procedures, specimens of tissue of the infected foot lesions were biopsied to be cultured, and for bacterial resistance analysis. Results: the sample consisted of 105 patients. The majority of patierns were men, over 50 years of age, married and with low educational level. There was bacterial growth in 95 of the 105 tissue cultures. In each positive culture only one germ was isolated. There was a high prevalence of germs of the Enterobacteriaceae family (51,5%). Gram-negative germs were isolated in 60% of cultures and the most individually isolated germs were the Gram-positive cocci, Staphylococcus aureus (20%) and Enterococcus faecalis (17,9%). Regarding antibiotic resistance rates, a high frequency of Staphylococcus aureus resistant to methicillin (63,0%) and to ciprofloxacin (55,5%) was found; additionally, 43,5% of the Gram-negative isolated germs were resistant to ciprofloxacin. Conclusions: the majority of patients were men, over 50 years of age, married and with low educational level. The most prevalent isolated germs from the infected foot lesions were Gram-negative bacteria, resistant to ciprofloxacin, and the individually most isolated germ was the methicillin resistant Staphylococcus aureus.

RESUMO Objetivo: identificar o perfil sociodemográfico, microbiológico e de resistência bacteriana em pacientes com pé diabético infectado. Métodos: tratou-se de estudo observacional, transversal que avaliou os perfis sóciodemográfico e microbiológico de pacientes portadores de pé diabético infectado internados em Pronto Socorro de referência. Os dados sociodemográficos foram coletados por meio de entrevista. Foram colhidos, durante os procedimentos cirúrgicos, fragmentos de tecidos das lesões podais infectadas para realização de cultura/antibiograma. Resultados: a amostra foi composta por 105 pacientes. O perfil sociodemográfico mais prevalente foi o de pacientes do sexo masculino, acima dos 50 anos, casados e com baixa escolaridade. Das 105 amostras de fragmentos de tecidos colhidos para realização de cultura e antibiograma, 95 foram positivas, com crescimento de um único germe em cada um dos exames. Houve predomínio de germes da família Enterobacteriaceae (51,5%). Germes Gram-negativos foram isolados em 60,0% das culturas e os espécimes mais isolados individualmente foram os cocos Gram-positivos, Staphylococcus aureus (20,0%) e Enterococcus faecalis (17,9%). Considerando-se os perfis de resistência bacteriana, verificou-se alta taxa de Staphylococcus aureus resistente à meticilina (63,0%) e à ciprofloxacino (55,5%); verificou-se, também, que 43,5% dos germes Gram-negativos eram resistentes à ciprofloxacino. Conclusões: o perfil sociodemográfico majoritário, foi o de homens, com mais de 50 anos e com baixa escolaridade. Concluímos que os germes mais prevalentes nas lesões podais dos pacientes diabéticos foram os Gram-negativos, resistentes ao ciprofloxacino e que o germe mais isolado individualmente foi o Staphylococcus aureus resistente à meticilina.

Comparison of cerebrospinal fluid lactate with physical, cytological, and other biochemical characteristics as prognostic factors in acute bacterial meningitis / Comparação do lactato no líquido cefalorraquidiano com as características físicas, citológicas e outros marcadores bioquímicos, como fator prognostico nas meningites bacterianas agudas

ABSTRACT Bacterial meningitis (BM) is associated with a high morbidity and mortality. Cerebrospinal fluid (CSF) lactate may be used as a prognostic marker of this condition. We hypothesized that CSF lactate levels would remain elevated in participants who died of acute BM compared with those who recovered from this disease. Objective: To evaluate the potential use of lactate and other CSF biomarkers as prognostic markers of acute BM outcome. Methods: This retrospective, longitudinal study evaluated dynamic CSF biomarkers in 223 CSF samples from 49 patients who fulfilled the inclusion criteria of acute BM, with bacteria identified by CSF culturing. The participants were grouped according to outcome: death (n = 9; 18.37%) and survival (n = 40; 81.63%). All participants received appropriate antibiotic treatment. Results: In the logistic regression model, lactate concentration in the final CSF sample, xanthochromia, and CSF glucose variation between the first and last CSF samples were predictors of a poor outcome (death). In contrast, decrease in CSF white blood cell count and CSF percentage of neutrophils, increase in the percentage of lymphocytes, and normalization of the CSF lactate concentration in the last CSF sample were predictors of a good prognosis. Conclusion: The study confirmed the initial hypothesis. The longitudinal analysis of CSF lactate is an important predictor of prognosis in acute BM.

RESUMO As meningites bacterianas (MB) estão associadas à alta morbidade e mortalidade. O lactato no líquido cefalorraquidiano (LCR) pode ser usado como biomarcador de prognóstico nas MB. A hipótese desse estudo é que os níveis de lactato no LCR se mantém elevados entre pacientes com MB aguda que evoluem para óbito, ao contrário do que ocorre em pacientes com bom prognóstico. Objetivo: Avaliar o uso potencial do lactato e outros marcadores no LCR como indicador de prognóstico na MB aguda. Métodos: Foi realizado um estudo retrospectivo longitudinal da dinâmica dos biomarcadores bioquímicos, celulares e físicos no LCR. Foram analisadas 223 amostras de 49 pacientes com MB aguda com bactérias identificadas por cultura do LCR. Os participantes foram divididos em dois grupos de acordo com o desfecho: óbito (n = 9; 18,37%) e não óbito (n = 40; 81,63%). Todos os participantes receberam antibioticoterapia adequada. Resultados: No modelo de regressão logística, as variáveis que diferiram significativamente entre os dois grupos foram concentração de lactato na amostra final de LCR, xantocromia e variação da concentração de glicose entre a primeira e a última amostra de LCR. A alteração desses fatores indicou desfechos negativos (óbito), enquanto a diminuição do número de leucócitos e da porcentagem de neutrófilos, assim como a normalização da concentração de lactato no LCR foram preditores de bom prognóstico. Conclusão: O estudo confirmou a hipótese inicial. A análise longitudinal do lactato no LCR é um importante preditor de prognóstico na MB aguda.

Microbiological analysis of contact lens cases: impact of the hospital environment / Análise microbiológica de estojos de lentes de contato: impacto do ambiente nosocomial

ABSTRACT Purpose: The aim of this study was to analyze the bacterial and fungal microbiota found in contact lens cases among two groups of patients to correlate the data on the habits of contact lens users and to evaluate whether there is a difference in the culture results between users of ridged and nonridged contact lens cases. Methods: Two groups (35 patients per group) were included, consisting of hospital workers and those who had not visited a hospital in the past 30 days, and a questionnaire regarding epidemiological data and habits related to contact lens and lens case use was administered. In addition, 140 samples collected from the right and left compartments of each lens case by swabbing the bottom of the wells were tested using bacterioscopy as well as fungal and bacterial cultures via computerized identification of the species. Results: No fungal growth was identified in any of the 70 contact lens cases; however, bacteria were found in 39 cases, and there was no statistical difference between the groups. Most bacteria (>85%) were gram-negative bacilli. Contamination inone compartment of the contact lens case elevated the risk of contamination of the other side (>80%). Moreover, contamination was statistically higher in the ridged cases than in nonridged cases (p=0.0149). Conclusion: The types of bacteria contaminating the cases are generally not seen in eye diseases associated with contact lens use, suggesting that other decisive variables are involved in eye infection from a contaminated lens or case. Fungal contamination of contact lens cases appears to be an exception. Ridged cases are commonly used by contact lens wearers and present a potential risk to eye health. In addition, the results of bacterial tests between hospital workers and those who did not visit a hospital were not significantly different.

RESUMO Objetivo: O objetivo deste trabalho foi analisar a microbiota bacteriana e fúngica encontrada em estojos de lentes de contato em dois grupos, correlacionar os dados sobre os hábitos de uso de lentes de contato e avaliar se há diferença na positividade das culturas entre os usuários estojos de lentes de contato com ranhuras e sem ranhuras. Métodos: Dois grupos foram formados, trabalhadores do hospital e pessoas que não visitaram o hospital (35 indivíduos por grupo), e um questionário foi aplicado sobre dados epidemiológicos e hábitos relacionados ao uso de lentes de contato e estojos de lentes. Além disso, 140 amostras, coletadas do compartimento direito e esquerdo de cada estojo de lente, esfregando o fundo dos mesmos, foram testadas por bacterioscopia e por culturas de fungos e bactérias, com identificação computadorizada da espécie. Resultados: Não houve crescimento fúngico em nenhum dos 70 estojos de lentes de contato, porém bactérias foram encontradas em 39; não houve diferença estatística entre os grupos. A maioria das bactérias (>85%) eram bacilos gram-negativos. Quando um compartimento estava contaminado, o risco de contaminação do outro compartimento era elevado (>80%). A contaminação foi estatisticamente maior nos estojos com ranhuras (p=0,0149). Conclusão: A contaminação dos estojos parece ocorrer por bactérias que, em geral, não são encontradas em doenças oculares associadas ao uso de lentes de contato, sugerindo que existem outras variáveis decisivas nas infecções oculares de uma lente ou estojo contaminado. Contaminação de estojos de lentes de contato com fungos parece ser uma exceção. O uso de estojos com ranhuras é uma prática comum e apresenta um risco potencial à saúde ocular. Não foram encontradas diferenças significativas nos resultados dos testes bacterianos entre trabalhadores hospitalares e pessoas que não visitaram o hospital.

Bacteriology of peritonsillar abscess: the changing trend and predisposing factors / Bacteriologia do abscesso peritonsilar: tendência de mudança e fatores predisponentes

Abstract Introduction: Peritonsillar abscess is the most common deep neck infection. The infectious microorganism may be different according to clinical factors. Objective: To identify the major causative pathogen of peritonsillar abscess and investigate the relationship between the causative pathogen, host clinical factors, and hospitalization duration. Methods: This retrospective study included 415 hospitalized patients diagnosed with peritonsillar abscess who were admitted to a tertiary medical center from June 1990 to June 2013. We collected data by chart review and analyzed variables such as demographic characteristics, underlying systemic disease, smoking, alcoholism, betel nut chewing, bacteriology, and hospitalization duration. Results: A total of 168 patients had positive results for pathogen isolation. Streptococcus viridans (28.57%) and Klebsiella pneumoniae (23.21%) were the most common microorganisms identified through pus culturing. The isolation rate of anaerobes increased to 49.35% in the recent 6 years (p = 0.048). Common anaerobes were Prevotella and Fusobacterium spp. The identification of K. pneumoniae increased among elderly patients (age > 65 years) with an odds ratio (OR) of 2.76 (p = 0.03), and decreased in the hot season (mean temperature > 26 °C) (OR = 0.49, p = 0.04). No specific microorganism was associated with prolonged hospital stay. Conclusion: The most common pathogen identified through pus culturing was S. viridans, followed by K. pneumoniae. The identification of anaerobes was shown to increase in recent years. The antibiotics initially selected should be effective against both aerobes and anaerobes. Bacterial identification may be associated with host clinical factors and environmental factors.

Resumo Introdução: O Abscesso Peritonsilar é a infecção cervical profunda mais comum. O microrganismo infeccioso pode ser diferente de acordo com os fatores clínicos. Objetivo: Identificar o principal agente causador do abscesso peritonsilar e investigar a relação entre o patógeno causador, os fatores clínicos do hospedeiro e a duração da hospitalização. Método: Este estudo retrospectivo incluiu 415 pacientes hospitalizados diagnosticados com abscesso peritonsilar que foram internados em um centro médico terciário de junho de 1990 a junho de 2013. Coletamos dados através da análise dos arquivos médicos dos pacientes e analisamos variáveis como características demográficas, doença sistêmica subjacente, tabagismo, alcoolismo, hábito de mascar noz de betel, bacteriologia e duração da hospitalização. Resultados: Um total de 168 pacientes apresentaram resultados positivos para isolamento de patógenos. Streptococcus viridans (28,57%) e Klebsiella pneumoniae (23,21%) foram os microrganismos mais comuns identificados pela cultura da secreção. A taxa de isolamento de anaeróbios aumentou para 49,35% nos últimos 6 anos (p = 0,048). Os anaeróbios comuns foram Prevotella e Fusobacterium spp. A identificação de K. pneumoniae aumentou em pacientes idosos (idade > 65 anos) com razão de chances (Odds Ratio - OR) de 2,76 (p = 0,03) e diminuiu na estação do calor (temperatura média > 26 °C) (OR = 0,49, p = 0,04). Nenhum microrganismo específico foi associado à hospitalização prolongada. Conclusão: O patógeno mais comumente identificado através da cultura de secreção foi S. viridans, seguido por K. pneumoniae. A identificação de anaeróbios mostrou ter aumentado nos últimos anos. Os antibióticos selecionados inicialmente devem ser efetivos contra aeróbios e anaeróbios. A identificação bacteriana pode estar associada a fatores clínicos e fatores ambientais do hospedeiro.

Epidemiology of diabetic foot infections in a reference tertiary hospital in India

Abstract Introduction The present study attempts to examine the microbial profile and antibiotic susceptibility of diabetic foot infections in the intensive care unit of a tertiary referral centre for diabetic foot. As part of the study, we also attempted to find the prevalence of blaNDM-like gene among carbapenem-resistant gram negative infections. Methodology A prospective study of 261 patients with diabetic foot infections was performed during the period between January 2014 and June 2014. Results A total of 289 isolates were obtained from 178 tissue samples from 261 patients, 156 (59.7%) males and 105 (40.2%) females, with a mean age of 58 years (-15 years), having diabetic foot infection. No growth was seen in thirty eight (17.6%) tissue samples. Out of the total samples, 44.3% were monomicrobial and 55.7% were polymicrobial. Gram negative pathogens were predominant (58.5%). Seven of the total isolates were fungal; 0.7% showed pure fungal growth and 1.7% were mixed, grown along with some bacteria. The most frequently isolated bacteria were Staphylococcus aureus (26.9%), followed by Pseudomonas aeruginosa (20.9%). Of the 58.5% gram negative pathogens, 16.5% were Enterobacteriaceae resistant to carbapenems. Among these isolates, 4 (25%) were positive for blaNDM-like gene. Among the rest, 18.6% were carbapenem-resistant Pseudomonas, among which 4 (36.3%) were blaNDM. Among the Staphylococci, 23.7% were methicillin-resistant Staphylococcus aureus. Conclusions Our results support the recent view that gram negative organisms, depending on the geographical location, may be predominant in DFIs. There is an increase in multidrug-resistant pathogens, especially carbapenem resistance and this is creeping rapidly. We need to be more judicious while using empiric antibiotics.

Microorganismos aislados de hemocultivos en niños con cáncer y neutropenia febril de alto riesgo en cinco hospitales de Santiago, Chile, período 2012-2015 / Microorganisms isolated from blood cultures in children with cancer and high-risk febrile neutropenia from five hospitals in Santiago, Chile, 2012-2015

Resumen Antecedentes: Los microorganismos aislados de hemocultivos (HC) en pacientes con neutropenia febril (NF) varían en el tiempo, siendo necesaria su vigilancia para orientar una terapia empírica adecuada. Objetivo: Identificar microorganismos aislados de HC y su perfil de resistencia (R) a antimicrobianos en niños con cáncer y NF de alto riesgo. Método: Estudio prospectivo, multicéntrico de episodios de NF de alto riesgo en pacientes bajo 18 años de edad, de cinco hospitales en Santiago de Chile, 2012-2015. Análisis de HC positivos. Resultados: Se analizaron 206 microorganismos en 185 episodios de NF de alto riesgo con HC positivos. Los aislados principales fueron bacilos gramnegativos (BGN) (46,6%) y cocáceas grampositivas (CGP) (45,1%) y los microorganismos más frecuentes Escherichia coli (22,8%), Staphylococcus coagulasa negativa (18,0%) y Klebsiella spp (16,5%). En resistencia (R) a antimicrobianos destaca: E. coli y Klebsiella spp 4,2 y 67,6% R a cefalosporinas de tercera generación (cefotaxima/ceftriaxona) respectivamente, 10,6 y 40,6% R a ciprofloxacina y 2,1 y 26,5% a amikacina, respectivamente. S. coagulasa negativa y S. aureus 86,4% y 22,2% R a oxacilina, Streptococcus grupo viridans 71% R a penicilina. Discusión: Este estudio actualiza la etiología y el perfil de R de microorganismos aislados en HC de niños con cáncer y NF de alto riesgo, herramienta esencial para el adecuado manejo de estos pacientes.

Background: Microorganisms isolated from blood cultures (BC) in patients with febrile neutropenia (NF) vary over time, requiring systematic monitoring to guide appropriate empirical therapy. Aim: To identify microorganisms isolated from BC and their antimicrobial resistance profile in children with cancer and high risk NF. Method: Prospective, multicenter study. The analysis included episodes of high-risk FN with positive BC in children under 18 years of age treated in five hospitals in Santiago, Chile, 2012-2015. Results: A total of 206 microorganisms were analyzed in 185 episodes of high-risk FN. The main isolates were Gram negative bacilli (46.6%) and Gram positive cocci (45.1%) and the most frequent microorganisms were Escherichia coli (22.8%), coagulase negative Staphylococcus (18.0%) and Klebsiella spp. (16.5%). Escherichia coli and Klebsiella spp showed 4.2% and 67.6% resistance to third generation cephalosporins (cefotaxime/ceftriaxone), 10.6% and 40.6% resistance to fluoroquinolones (ciprofloxacin) and 2.1% and 26.5% to amikacin, respectively. Coagulase negative Staphylococcus and Staphylococcus aureus had 86.4% and 22.2% resistance to oxacillin, Streptococcus viridans group had 71% resistance to penicillin. Discussion: This study updates the etiology and resistance profile of microorganisms isolated in BC from children with cancer and high risk FN, an essential tool for the adequate management of these patients.

Prevalencia y perfil de susceptibilidad antimicrobiana en bacterias aisladas de úlceras crónicas infectadas en adultos / Prevalence and susceptibility pattern of bacteria isolated from infected chronic wounds in adult patients

Resumen Introducción: Las úlceras crónicas son un problema de salud pública, agravándose por infecciones bacterianas causadas principalmente por agentes resistentes. Objetivo: Estudiar prevalencia y perfil de susceptibilidad en bacterias aisladas de úlceras crónicas en pacientes adultos. Pacientes y Métodos: Pacientes atendidos en la Fundación Instituto Nacional de Heridas entre mayo y julio de 2014, con úlceras crónicas en extremidades inferiores con signos inflamatorios clínicos. Las muestras fueron cultivadas en aerobiosis y anaerobiosis y para la identificación bacteriana se empleó el sistema de galerías API (Biomerieux). La susceptibilidad in vitro se evaluó según el método de Kirby Bauer. Resultados: Se reclutaron 73 pacientes, entre quienes 46 presentaron úlceras infectadas, diagnosticándose 33 úlceras venosas con predominio de infección polimicrobiana y 10 úlceras de pie diabético con predominio de infección monomicrobiana (p ≤ 0,05). Se aislaron 68 cepas de los 46 pacientes con úlcera infectada. Las enterobacterias predominaron en infección monomicrobiana (p ≤ 0,05) y los demás grupos bacterianos fueron levemente más frecuentes en infección polimicrobiana. La especie prevalente fue Staphylococcus aureus (24%) seguida de Pseudomonas aeruginosa (18%). Cincuenta cepas (77%) presentaron resistencia a uno o más antibacterianos. Destacamos resistencia de S. aureus a ciprofloxacina (50%) y cefoxitina (37,5%) identificándose así resistencia a meticilina en la comunidad (SARM-AC), siendo todas sensibles a cotrimoxazol. Las enterobacterias presentaron resistencia a sensibilidad a amikacina (95,5%), P. aeruginosa evidenció resistencia a ciprofloxacina (33,3%) con alta sensibilidad a gentamicina (91,7%) y amikacina (83,3%), mientras Acinetobacter spp presentó resistencia a ciprofloxacina y ceftazidima en 60%, con 100% de sensibilidad a imipenem. Streptococcus β hemolítico presentó 50% de resistencia a clindamicina y penicilina. Conclusión: Estos datos entregan información epidemiológica de infecciones de úlceras crónicas, representando un apoyo al diagnóstico, tratamiento y manejo de esta patología.

Background: Chronic wounds are considered a public health problem that may be complicated by bacterial infections, mainly caused by resistant strains. Aim: To study the bacteria prevalence and antimicrobial susceptibility in samples from adult patients with chronic wounds. Methods: Patients treated at National Institute of Wounds Foundation between May and July 2014, with chronic ulcers in lower extremities with clinical inflammatory signs were recluted. Samples were cultured in aerobic and anaerobic atmosphere and species identification was performed by API (Biomerieux) galleries. The in vitro susceptibility was evaluated according to the Kirby Bauer method. Results: From 73 patients, 46 had infected wounds most of them were venous ulcers (33) with prevalence in polymicrobial infections and 10 with foot-diabetes ulcers with prevalence in monomicrobial infections (p ≤ 0.05). Sixty-eight strains were isolated and Enterobacteriaceae were predominant in monomicrobial infection (p ≤ 0.05) and the other groups were slightly higher in polymicrobial infection. The main species were Staphylococcus aureus (24%) followed by P. aeruginosa (18%). Fifty strains (77%) were resistant or multi-resistance. We emphasize resistance of S. aureus to ciprofloxacin (50%) and cefoxitin (37.5%), thus identifying resistance to methicillin in the community (CA-SAMR), all of which are sensitive to cotrimoxazole. Enterobacteria showed sensitivity to amikacin (95.5%), P. aeruginosa showed resistance to ciprofloxacin (33.3%) with high sensitivity to gentamicin (91.7%) and amikacin (83.3%), while Acinetobacter spp showed resistance to ciprofloxacin and ceftazidime in 60%, with 100% sensitivity to imipenem. 50% Streptococcus β hemolytic showed resistance to clindamycin and penicillin. Conclusion: These data provide epidemiological information on chronic wound infections, representing support for diagnosis, treatment and management of this pathology.

Impacto das mudanças da microbiologia na peritonite bacteriana espontânea em três diferentes períodos ao longo de 17 anos / Impact of microbiological changes on spontaneous bacterial peritonitis in three different periods over 17 years

ABSTRACT BACKGROUND: Spontaneous bacterial peritonitis is a serious complication in cirrhotic patients, and changes in the microbiological characteristics reported in the last years are impacting the choice of antibiotic used for treatment. OBJECTIVE: The aim of the present study is to evaluate the changes in the epidemiology and bacterial resistance of the germs causing spontaneous bacterial peritonitis over three different periods over 17 years. METHODS: All cirrhotic patients with spontaneous bacterial peritonitis and positive culture of ascites fluid were retrospectively studied in a reference Hospital in Southern Brazil. Three periods were ramdomly evaluated: 1997-1998, 2002-2003 and 2014-2015. The most frequent infecting organisms and the sensitivity in vitro to antibiotics were registered. RESULTS: In the first period (1997-1998) there were 33 cases, the most common were: E. coli in 13 (36.11%), Staphylococcus coagulase-negative in 6 (16.66%), K. pneumoniae in 5 (13.88%), S. aureus in 4 (11.11%) and S. faecalis in 3 (8.33%). In the second period (2002-2003), there were 43 cases, the most frequent were: Staphylococus coagulase-negative in 16 (35.55%), S. aureus in 8 (17.77%), E. coli in 7 (15.55%) and K. pneumoniae in 3 (6.66%). In the third period (2014-2015) there were 58 cases (seven with two bacteria), the most frequent were: E. coli in 15 (23.1%), S. viridans in 12 (18.5%), K. pneumoniae in 10 (15.4%) and E. faecium 5 (7.7%). No one was using antibiotic prophylaxis. Considering all staphylococci, the prevalence increased to rates of the order of 50% in the second period, with a reduction in the third period evaluated. Likewise, the prevalence of resistant E. coli increased, reaching 14%. CONCLUSION: There was a modification of the bacterial population causing spontaneous bacterial peritonitis, with high frequency of gram-positive organisms, as well as an increase in the resistance to the traditionally recommended antibiotics. This study suggests a probable imminent inclusion of a drug against gram-positive organisms in the empiric treatment of spontaneous bacterial peritonitis.

RESUMO CONTEXTO: A peritonite bacteriana espontânea é uma complicação séria em pacientes cirróticos e as alterações nas características microbiológicas relatadas nos últimos anos podem afetar a escolha do antibiótico utilizado no tratamento. OBJETIVO: Os objetivos do presente estudo são avaliar as mudanças na epidemiologia e perfil de resistência bacteriana dos germes causadores de peritonite bacteriana espontânea em três períodos diferentes ao longo de 17 anos. MÉTODOS: Todos os pacientes cirróticos com peritonite bacteriana espontânea e cultura positiva de fluido ascítico foram estudados retrospectivamente em um hospital de referência no Sul do Brasil. Foram avaliados três diferentes períodos selecionados de forma randômica: 1997-1998, 2002-2003 e 2014-2015. Os organismos infecciosos mais frequentes e a sensibilidade in vitro a antibióticos foram registados. RESULTADOS: No primeiro período (1997-1998) houve 33 casos; os mais comuns foram: E. coli em 13 (36,1%), Staphylococcus coagulase-negativo em 6 (16,7%), K. pneumoniae em 5 (13,9%), S. aureus em 4 (11,1%) e S. faecalis em 3 (8,3%). No segundo período (2002-2003), houve 43 casos, os mais frequentes foram: Staphylococus coagulase-negativo em 16 (35,5%), S. aureus em 8 (17,8%), E. coli em 7 (15,5%) e K. pneumoniae em 3 (6,7%). No terceiro período (2014-2015), houve 58 casos (sete com duas bactérias), os mais frequentes foram: E. coli em 15 (23,1%), S. viridans em 12 (18,5%), K. pneumoniae em 10 (15,4%) e E. faecium 5 (7,7%). Nenhum paciente estava usando profilaxia antibiótica. Quando considerados todos os estafilococos, a prevalência aumentou para taxas da ordem de 50% no segundo período, apresentando redução no terceiro período avaliado. Do mesmo modo, a prevalência de E coli resistente aumentou, chegando a 14%. CONCLUSÃO: Houve modificação da população bacteriana causadora de peritonite bacteriana espontânea, com alta frequência de organismos gram-positivos, bem como aumento da resistência aos antibióticos tradicionalmente recomendados. Este estudo sugere uma provável inclusão iminente de um medicamento contra organismos gram-positivos no tratamento empírico da peritonite bacteriana espontânea.

Efficacy of removal of cariogenic bacteria and carious dentin by ablation using different modes of Er: YAG lasers

The primary objective of this in vitro study was to evaluate the efficiency of removal of cariogenic bacteria and carious dentin by ablation using two lasers: fluorescence-feedback controlled (FFC) Er:YAG laser and different pulses of Er:YAG laser based on variable square pulse technology (VSPt). The secondary objective was to measure the temperature during laser ablation of carious tissue. Seventy-two extracted human molars were used in this study. Sixty teeth with carious dentin were randomly divided into four experimental groups according to the treatment for caries removal: group 1: 400 µs (FFC group); group 2: super short pulse (SSP group, 50 µs pulse); group 3: medium short pulse (MSP group, 100 µs pulse); group 4: short pulse (SP group, 300 µs pulse) and one positive control group with no treatment. Twelve teeth without carious lesion were used as a negative control group. After caries removal, swabs were taken with cotton pellets and real-time PCR analysis was performed. During caries ablation, a thermal infrared camera was used to measure the temperature changes. In all experimental groups, specimens were free of bacterial contamination after the treatment. In the SSP, MSP and SP groups, temperatures measured during caries ablation were significantly higher compared to temperatures in the FFC group (P<0.001). In this in vitro study, laser treatment for removal of carious dentin and cariogenic bacteria was an efficient treatment modality without causing excessive temperatures that might adversely affect pulp vitality.

Sepsis neonatal tardía nosocomial en una unidad de terapia intensiva: agentes etiológicos y localización más frecuente / Late onset neonatal sepsis in an intensive care neonatal unit: etiological agents and most frequent location

Resumen Introducción: La sepsis neonatal nosocomial (SNN) es una entidad frecuente en las unidades de cuidados intensivos, donde causa una gran morbimortalidad. La ubicación más frecuente es bacteriemia, seguido de neumonía asociada a ventilador mecánico y vía urinaria. Objetivo: Conocer la etiología y localización más frecuente de la infección en el SNN. Población, Material y Métodos: Estudio retrospectivo, de prevalencias de enero a diciembre de 2015, realizado en la Unidad de Cuidados Intensivos Neonatal de un hospital de alta complejidad. Fueron incluidos todos los neonatos. Resultados: Se incluyeron 70 pacientes, se analizaron 88 episodios de SNN. La localización más frecuente fue sangre 40% de los casos, seguido de orina y aspirado traqueal en 25% respectivamente. Los microorganismos más frecuentemente aislados fueron Staphylococcus de diferentes tipos, seguido de Acinetobacter baumannii multi-resistente. La afectación del SNC fue de 32%. La mortalidad fue de 34%, elevándose a 50% ante un segundo episodio de SNN. La terapia empírica de elección fue vancomicina y carbapenem, ajustándose a antibiograma. Conclusiones: La infección más frecuente fue la bacteremia, principalmente por Staphylococcus resistentes a meticilina. La afectación del SNC fue elevada, lo mismo que la mortalidad.

Introduction: Nosocomial neonatal sepsis (NNS) is a frequent entity in intensive care units, causing great morbidity and mortality. The most frequent site is blood, followed by lungs and urine. Objective: To know the etiology and most frequent localization of infection in the NNS. Population, Material and Methods: Cross sectional study, from January to December 2015, performed in a teaching hospital. All newborns infants were included. Results: 70 patients were included, 88 episodes of NNS were analyzed. The most frequent localization was bacteremia in 40% of cases, followed by urinary tract infection and VAP in 25% respectively. The bacteria most frequently isolated were staphylococci of different types, followed by multiresistant Acinetobacter. The CNS involvement was 32%. Mortality was 34%, rising up to 50% with a second episode of NNS. The empirical therapy of choice was vancomycin and carbapenem, adjusting to antibiogram. Conclusions: The most frequent infection was bacteremia, mainly by staphylococci resistant to methicillin. CNS involvement was elevated, as well as mortality.

Epidemiología de las infecciones urinarias asociadas a catéter y no asociadas a catéter en un hospital universitario de tercer nivel / Nosocomial urinary tract infection: an analysis beyond urinary catheterization

Resumen Introducción: Las infecciones urinarias asociadas a la atención de la salud (ITU-AAS) representan un importante problema sanitario, siendo poco conocidas sus características cuando no están asociadas a cateterización urinaria u ocurren fuera de unidades de cuidados intensivos (UCI). Objetivos: Determinar las características de los pacientes con ITU-AAS, etiología y susceptibilidad antimicrobiana de las mismas, tanto asociadas a catéter (ITU-C) como no asociadas a catéter (ITU-noC), en UCI y en sala general. Materiales y Métodos: Se realizó un estudio analítico retrospectivo de corte transversal entre 2009 y 2013 en un hospital universitario de tercer nivel. Se identificaron todos los episodios de ITU-AAS, diferenciándolas en ITU-C e ITU-noC. Resultados: Se incluyeron 253 episodios de ITU-AAS, siendo más frecuentes las ITU-C (60,9%) respecto a ITU-noC. Un 37,4% de ITU-noC y 59,7% de ITU-C ocurrieron en UCI. Los microorganismos aislados más frecuentemente fueron Escherichia coli, Klebsiella pneumoniae y Enterococcus sp. El 19% de los bacilos gramnegativos fueron productores de β-lactamasa de espectro extendido, siendo su frecuencia similar en ambos grupos. Conclusión: Las co-morbilidades de los pacientes con ITU-AAS, los agentes etiológicos responsables y sus correspondientes espectros de sensibilidad, fueron similares en los grupos de ITU-C e ITU-noC, tanto en sala general como en UCI.

Introduction: Nosocomially acquired urinary tract infections (NAUTI) represent an important public health issue, but its characteristics when they are not catheter associated (CA-UTI) or when they take place outside intensive care units (ICU) are poorly understood. Objectives: To determine the patients' characteristics, etiology and antimicrobial susceptibility of NAUTI, both CA-UTI and no CA-UTI, in general ward and ICU. Methods: We conducted a retrospective analytic cross-sectional study, between 2009 and 2013, in a third level universitary hospital. All NAUTI episodes were identified, classifying them as CA-UTI and no CA-UTI. Results: We included 253 episodes of NAUTI, being CA-UTI (60,9%) more frequent than no CA-UTI. A 37,4% of no CA-UTI and 59,7% of CA-UTI were identified in ICU. The most frequently isolated microorganisms were Escherichia coli, Klebsiella pneumoniae and Enterococcus sp. A 19% of extended spectrum betalactamase producing gram negative bacilli were found, without differences between groups. Conclusion: Patients's comorbidities, microorganisms associated to NAUTI and its antimicrobial susceptibility were similar in CA-UTI and no CA-UTI, as in general ward and ICU.

Endocarditis infecciosa asociada a catéter de hemodiálisis: hallazgos clínicos y ecocardiográficos / Infective endocarditis associated with hemodialysis catheters: clinical and ehocardiographic findings

Resumen: Hallazgos clínicos y ecocardiográficos en pacientes con endocarditis infecciosa (E.I.) asociada a catéter de hemodiálisis (CHD) fueron comparados con sujetos controles con E.I. "habitual". Pacientes y métodos: Del total de registros ecocardiográficos de una Clínica privada de Antofagasta entre 2009 y 2014, 4 pacientes presentaban E.I. asociada CHD (E.I.-CHD) y 16 otro tipo de E.I. (controles). Se compararon ambos grupos clínicamente y en las distintas modalidades de ecografía, para evaluar el aporte de cada una de ellas en el diagnóstico, manejo y comprensión del mecanismo de producción de la E.I. Resultados: El periodo del inicio de los síntomas hasta la hospitalización y el comprendido entre ésta hasta el fallecimiento fue variable, con tendencia a fallecimiento más precoz en el grupo E.I.-CHD (promedio 14,6 vs 20,6 días en el grupo control). La edad en E.I.-CHD fue mayor (65 versus 62.2 años), con mayor incidencia de las 3 comorbilidades más frecuentes: hipertensión arterial (100% versus 56,25%), diabetes mellitus (75% versus 50%) e insuficiencia cardíaca (75% versus 31,25%). La mortalidad fue 18.75% en el grupo control y 75% en la E.I.-CHD. En los pacientes con E.I.-CHD se aisló: Cándida (50%), Bacilos gram negativo (Stenotrophomonas maltophilia) (25%) y SAMR (25%) mientras que en el grupo control fueron aislados Enterococcus faecalis (25%), Streptococcus viridans (12.5%), Streptococcus spp (6.25%), Staphylococcus aureus (6.25%), Streptococcus grupo C (6.25%), Abiotrophia defectiva (6.25%) y Streptococcus pneumoniae (6.25). En 31.25% de los casos los hemocultivos fue-ron negativos. La localización más frecuente de las vegetaciones en los pacientes con E.I.-CHD correspondió a la pared de AD, sitio de impacto del jet del CHD, en un 100%, seguida por CHD 50%, tricúspide 25% y aórtica 25%. En los controles las localizaciones fueron 75% en válvula aórtica y 25% en válvula mitral. En el grupo de E.I.-CHD, la mitad presentó disfunción sistólica e insuficiencia valvular, mientras que en el grupo control fue predominante la insuficiencia valvular (62,5%) seguida por la perforación de velo (25%). Conclusión: En las E.I.-CHD se aislaron gérmenes asociados a un peor pronóstico (hongos o bacterias atípicas), con altísima mortalidad. La localización principal de las vegetaciones fue en la pared de la aurícula derecha (AD), alrededor de la desembocadura de la vena cava inferior (VCI), sitio de impacto del jet del CHD, y en el tercio distal del catéter. Clinical and echocardiographic findings in patients with infective endocarditis (I.E.) associated to the presence of hemodialysis catheters (HDC) were compared to those in subjects with other types of I.E.

Abstracts: Methods: Between 2009 and 2014 an echocardiographic diagnosis of I.E. was established in 4 subjects with a hemodialysis catheter in place and 16 patients had a common variety of I.E. (controls). Clinical and echocardiographic findings, including echocardiographic modalities were compared between groups. Results: Time from onset of symptoms and time to patient death were shorter in I.E.-HDC patients compared to controls (mean 14.6 vs 20.6 days, respectively. I.E. -HDC patients tended to be older (65.0 vs 62.2 years old). The incidence of main comorbidities was higher in I.E.-HDC: hypertension (100% vs 56.2%), diabetes (75 vs 59%) and heart failure (75% vs 31.2%), respectively. Mortality was much higher in I.E-HDC (74% vs 18%). Infective agents also differed between groups: I.E.-HDC was associate to C albicans (50%), Gram negative rods (Stenotrophomonas maltophilia) (25%) y SAMR (25%). In contrast, the agents involved in controls were E faecalis (25%), S viridans (12.5%), S. group C (6.25%), S aureus (6,25%), group C Streptococcus (6.25%), Abiotrophic defectiva (6.25%) and S pneumoniae (6.25%). Overall, blood cultures were negative in 31.2% patients. Among patients with I.E.-HDC vegetations were most commonly found at the right atrial wall (100%), on the catheter (50%), at the tricuspid valve (25%) and at the aortic valve (25%). In non I.E.-HDC, vegetations were located at the aortic valve (75%) and the mitral valve (25%). Half the patients with I.E.- HDC patients presented ventricular dysfunction and valvular regurgitation while control patients had predominantly valvular insufficiency (62.5%) or leaflet perforation (25%). Conclusion: Mortality in I.E.-HDC patients was very high, associated to the presence of aggressive microbial or fungal agents. Vegetations were most commonly located at the right atrial wall, around de junction with the inferior vena cava and on the catheter itself.

Etiología y resistencia a antimicrobianos de la infección no complicada del tracto urinario / Etiology and antimicrobial resistance of uncomplicated urinary tract infections

La infección urinaria no complicada en mujeres es un motivo frecuente de consulta e indicación de antimicrobianos. El objetivo de este estudio fue definir etiología y resistencia a antimicrobianos en episodios de infección urinaria no complicada. Este estudio prospectivo incluyó mujeres premenopáusicas no embarazadas, con infección urinaria no complicada, que consultaron en un hospital público y tres centros privados de las ciudades de Buenos Aires y La Plata (2011-2013). La edad media de 138 pacientes con infección confirmada por urocultivo fue 28 años. El diagnóstico fue cistitis en 97 (70%) y pielonefritis en 41 (30%). Las frecuencias de los microorganismos aislados fueron: Escherichia coli 97 (70%), Staphylococcus saprophyticus 24 (17%), Proteus spp. 10 (7%), Klebsiella spp. 5 (4%), Enterococcus spp. 1 (0.7%) y Pseudomonas aeruginosa 1 (0.7%). Las frecuencias de resistencia a antimicrobianos fueron: ampicilina-sulbactam 51 (37%), cefalexina 39 (28%), trimetoprima/sulfametoxazol 31 (22%), nitrofurantoína 17 (12%), gentamicina 10 (7%) y ciprofloxacina 7 (5%). La frecuencia de resistencia a ampicilina-sulbactam, trimetoprima/sulfametoxazol y cefalexina es mayor que las previamente publicadas en Argentina, lo que limita su recomendación para el tratamiento empírico. Una mejor comprensión de la etiología y la susceptibilidad antimicrobiana local permite el diseño de pautas más adecuadas para el tratamiento empírico.

Uncomplicated urinary tract infections rank among the most frequent bacterial infections in women in the outpatient setting and represent a major cause of antimicrobial prescription. The aims of this study were to assess frequencies and antimicrobial resistance of current uropathogens causing uncomplicated urinary tract infection. In a prospective multicenter study, patients were recruited in ambulatory settings of four participating hospitals between June 2011 and December 2013. We analyzed 138 patients that met clinical and bacteriological diagnostic criteria. The mean age was 28 years. Cystitis was defined in 70% (n: 97) and pyelonephritis in 30% (n: 41). Frequencies of isolated microorganisms were: Escherichia coli 70% (n: 97), Staphylococcus saprophyticus 17% (n: 24), Proteus spp. 7% (n: 10), Klebsiella spp. 4% (n: 5), Enterococcus spp. and Pseudomonas aeruginosa 1 (0.7%) each. The antimicrobial resistance was: ampicillin-sulbactam 37% (n: 51) cephalexin 28% (n: 39), trimethoprim/sulfamethoxazole 22% (n: 31), nitrofurantoin 12% (n: 17), gentamicin 7% (n: 10) and ciprofloxacin 5% (n: 7). The levels of resistance found for ampicillin-sulbactam, trimethoprim/sulfamethoxazole and cephalexin were higher than those previously reported in Argentina. A better knowledge of the etiology and local antimicrobial susceptibility allows the design of more adequate guidelines for empirical treatment.

Direct identification from positive blood broth culture by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS)

ABSTRACT Bloodstream infections (BSIs) are among the most concerning bacterial infections. They are one of the leading causes of morbidity and mortality, and occur in 30-70% of critical care patients. The prompt identification of the causative microorganism can help choosing the appropriate antimicrobial therapy that will lead to better clinical outcomes. Blood culture is one of the most relevant tests for microbiological diagnosis of bacterial infections. The introduction of the MALDI-TOF microbiological diagnosis significantly decreased the time of identifying microorganisms. However, it depends on the growth on solid culture medium. In this study, 538 bottles of positive blood cultures were evaluated to test the accuracy of an in house modified protocol. The study sample consisted of 198 Gram-negative and 350 Gram-positive bacteria. In all, 460 (83.94%) species were identified based on the direct plate findings. The protocol allowed the identification of 185/198 (93.43%) of the Gram-negative bacteria, including aerobes, anaerobes, and non-fermenters, and 275/350 (78.85%) of the Gram-positive bacteria. The proposed method has the potential to provide accurate results in comparison to the traditional method with the potential to reduce the turnaround time for the results and optimize antimicrobial therapy in BSI.

Changes in the conjunctival bacterial flora of patients hospitalized in an intensive care unit / Mudanças na flora bacteriana conjuntival de pacientes internados em unidade de terapia intensiva

ABSTRACT Purpose: To identify the changes in aerobic conjunctival bacterial flora and to correlate culture results with physical health and the duration of patients' hospitalization in an intensive care unit (ICU). Methods: Patients hospitalized in the ICU were included in this study. Conjunctival cultures from all patients were obtained using a standard technique on days 1, 3, 7, and 14. Swabs were plated on nonselective (blood agar) and enriched (chocolate agar) media within one hour. Visible colonies were isolated, and standard microbiological techniques were used to identify the bacteria. The frequency, identity, and correlation of culture results with patients' physical findings and the duration of hospitalization were determined. Results: We obtained 478 cultures (day 1, 270; day 3, 156; day 7, 36; and day 14, 16) from 135 patients; 288 (60.2%) cultures were positive, and 331 microorganisms were isolated. The most frequently isolated microorganism from the cultures was coagulase-negative Staphylococcus species (n=210/331, 63.5%), and the others were Corynebacterium diphtheriae (n=52/331, 15.7%), S. aureus (n=26/331, 7.9%), gram-negative bacilli other than Pseudomonas (n=14/331, 4.2%), Neisseria species (n=8/331, 2.4%), Pseudomonas aeruginosa (n=6/331, 1.8%), Haemophilus influenzae (n=7/331, 2.1%), Acinetobacter species (n=6/331, 1.8%), and Streptococcus species (n=2/331, 0.6%). The frequency of positive cultures significantly increased (p<0.03) with time. Conclusions: Prolonged hospitalization significantly predisposes to bacterial colonization. The colonization rate of S. aureus and Neisseria spp. increased significantly after one week.

RESUMO Objetivo: Identificar as mudanças na flora bacteriana aeróbia da conjuntiva e correlacionar os resultados da cultura com o estado de saúde física e a duração da hospitalização em pacientes em uma unidade de terapia intensiva (UTI). Método: Pacientes que estavam na UTI foram incluídos neste estudo. Culturas conjuntivais foram obtidas nos dias 1, 3, 7 e 14 de todos os pacientes com uma técnica normalizada. Zaragatoas foram semeadas em placas não seletivas (ágar sangue) e enriquecidas (ágar chocolate) dentro de uma hora. Colônias visíveis foram separadas, isoladas, e identificadas utilizando técnicas microbiológicas convencionais. A frequência, identificação e correlação da cultura resulta com achados físicos e a duração da hospitalização foram determinados. Resultados: Um total de 478 culturas (no primeiro dia 270, terceiro dia 156, sétimo dia 36 e dia catorze 16 culturas) foram obtidas de 135 pacientes hospitalizados durante o estudo. Duzentos e oitenta e oito (60,2% de todas as culturas obtidas) culturas foram positivas. Trezentos e trinta e um microrganismos foram isolados a partir dessas culturas. Em todos os grupos, o microrganismo mais frequentemente isolado foi o Staphylococcus species coagulase negativo (n=210/331, 63,5% de todos os microrganismos isolados). Outras bactérias isoladas foram Corynebacterium diphteriae (n=52/331, 15,7%), Staphylococcus aureus (n=26/331, 7,9%), bacilos Gram-negativos que não sejam Pseudomonas (n=14/331, 4,2%), Neisseria species (n=8/331, 2,4%), Pseudomonas aeruginosa (n=6/331, 1,8%), Haemophilus influenzae (n=7/331, 2,1%), Acinetobacter species (n=6/331, 1,8%), e Streptococcus species (n=2/331, 0,6%). Como o tempo de hospitalização prolongada, a positividade em culturas aumentou significativamente (p<0,03). Conclusões: hospitalização prolongada predispõe significativamente a frequência de colonização bacteriana. A taxa de colonização de S. aureus e Neisseria spp. aumentou significativamente depois de uma semana.

Septic arthritis of the knee: clinical and laboratory comparison of groups with different etiologies

OBJECTIVES: To clinically and epidemiologically characterize a population diagnosed with and treated for septic arthritis of the knee, to evaluate the treatment results and to analyze the differences between patients with positive and negative culture results, patients with Gram-positive and Gram-negative bacterial isolates and patients with S. aureus- and non-S. aureus-related infections. METHODS: One hundred and five patients with septic knee arthritis were included in this study. The clinical and epidemiological data were evaluated. Statistical analysis was performed to compare patients with and without an isolated causative agent, patients with Gram-positive and Gram-negative pathogens and patients with S. aureus-related and non S. aureus-related infections. RESULTS: Causative agents were isolated in 81 patients. Gram-positive bacteria were isolated in 65 patients and Gram-negative bacteria were isolated in 16 patients. The most commonly isolated bacterium was S. aureus. Comparing cases with an isolated pathogen to cases without an isolated pathogen, no differences between the studied variables were found except for the longer hospital stays of patients in whom an etiological agent was identified. When comparing Gram-positive bacteria with Gram-negative bacteria, patients with Gram-positive-related infections exhibited higher leukocyte counts. Patients with S. aureus-related infections were more frequently associated with healthcare-related environmental encounters. CONCLUSION: S. aureus is the most common pathogen of septic knee arthritis. Major differences were not observed between infections with isolated and non-isolated pathogens and between infections with Gram-positive and Gram-negative bacteria. S. aureus infections were more likely to be associated with a prior healthcare environment exposure.

Secondary bacterial isolates from previously untreated Buruli ulcer lesions and their antibiotic susceptibility patterns in Southern Nigeria

Abstract INTRODUCTION: Mycolactones, secreted by Mycobacterium ulcerans, were previously believed to prevent super infection in Buruli ulcer lesions. However, little is known about secondary bacterial infections in these lesions. This study evaluated contaminating bacterial flora and their antibiotic susceptibility patterns in cases of previously untreated Buruli ulcer disease from three states in Southern Nigeria. METHODS A prospective analysis was conducted between January and June of 2015 using wound swabs from eligible patients with Buruli ulcer disease, confirmed by quantitative-polymerase chain reaction, with active ulcers. Microbiological analyses including isolation of bacteria, species identification of isolates, and drug susceptibility tests were performed. RESULTS Of 51 patients, 27 (52.9%) were female. One or more bacterial species of clinical importance was isolated from each patient. A total of 17 different microbial species were isolated; 76.4% were Gram-negative and 23.6% were Gram-positive isolates. The most common bacterial species detected was Staphylococcus aureus (24%), followed by Aeromonas hydrophila (13%), Pseudomonas aeruginosa (13%), and Klebsiella pneumoniae (11%). Drug susceptibility tests showed a particularly high frequency of resistance to commonly used antimicrobials in Nigeria for Staphylococcus aureus. CONCLUSIONS Super bacterial infections occur in Buruli ulcer lesions in Nigeria, and these infections are associated with high rates of resistance to commonly used antibiotics in the country.