Ventilator-associated pneumonia: incidence, microbial etiology and antimicrobial resistance profile / Pneumonia associada à ventilação mecânica: incidência, etiologia microbiana e perfil de resistência antimicrobiana / Neumonía asociada a ventilador: incidencia, etiología microbiana y perfil de resistencia antimicrobiana

Background and Objectives: Infections caused by multi-drug resistant microorganisms have a great clinical and economic impact. The present study proposed to determine and assess ventilator-associated pneumonia (VAP) incidence in an Intensive Care Unit (ICU), to establish the profile of hospitalized patients and to determine the frequency of microorganisms isolated as well as their antimicrobial resistance profile. Methods: A descriptive, documental study, with a quantitative approach, carried out at a teaching hospital. Participants were all individuals admitted to the General ICU who developed VAP in 2018 and 2019. Results: During the study, 146 patients were diagnosed with VAP, with an incidence of 23.66/1000 patient-days on mechanical ventilation. The median age of patients was 52.5 years and most of them were man. One hundred and eight microorganisms were isolated in cultures, the majority being gram-negative bacteria. Non-fermenting bacteria were the most frequent (n=46; 42.6%), followed by enterobacteria (n=42; 38.9%). Staphylococcus aureus was the most frequent microorganism among gram-positive (n=17; 15.7%). The most frequent multi-drug resistant bacteria were Acinetobacter baumannii and Enterobacter spp. No microorganism showed colistin and vancomycin resistance. Patients infected with multi-drug resistant bacteria were hospitalized longer when compared to other patients. Conclusions: VAP incidence was high. The knowledge of the etiologic agents of VAP and their antimicrobial resistance profile is fundamental to support the elaboration of institutional treatment protocols as well as assist in empirical antibiotic therapy.(AU)

Justificativa e Objetivos: As infecções causadas por microrganismos multirresistentes têm grande impacto clínico e econômico. O presente estudo propôs determinar e avaliar a incidência de pneumonia associada à ventilação mecânica (PAV) em uma Unidade de Terapia Intensiva (UTI), estabelecer o perfil dos pacientes internados e determinar a frequência de microrganismos isolados, bem como seu perfil de resistência antimicrobiana. Métodos: Estudo descritivo, documental, com abordagem quantitativa, realizado em um hospital universitário. Participaram todos os indivíduos admitidos na UTI Geral que desenvolveram PAV em 2018 e 2019. Resultados: Durante o estudo, 146 pacientes foram diagnosticados com PAV, com incidência de 23,66/1000 pacientes-dia em ventilação mecânica. A idade mediana dos pacientes foi de 52,5 anos e a maioria era do sexo masculino. Cento e oito microrganismos foram isolados em culturas, sendo a maioria bactérias gram-negativas. As bactérias não fermentadoras foram as mais frequentes (n=46; 42,6%), seguidas das enterobactérias (n=42; 38,9%). Staphylococcus aureus foi o microrganismo mais frequente entre os Gram-positivos (n=17; 15,7%). As bactérias multirresistentes mais frequentes foram Acinetobacter baumannii e Enterobacter spp. Nenhum microrganismo apresentou resistência à colistina e vancomicina. Pacientes infectados com bactérias multirresistentes ficaram mais tempo internados quando comparados a outros pacientes. Conclusões: A incidência de PAV foi alta. O conhecimento dos agentes etiológicos da PAV e seu perfil de resistência antimicrobiana é fundamental para subsidiar a elaboração de protocolos institucionais de tratamento, bem como auxiliar na antibioticoterapia empírica.(AU)

Justificación y Objetivos: Las infecciones causadas por microorganismos multirresistentes tienen un gran impacto clínico y económico. El presente estudio se propuso determinar y evaluar la incidencia de neumonía asociada a ventilación mecánica (NAV) en una Unidad de Cuidados Intensivos (UCI), establecer el perfil de pacientes hospitalizados y determinar la frecuencia de microorganismos aislados así como su perfil de resistencia antimicrobiana. Métodos: Estudio descriptivo, documental, con abordaje cuantitativo, realizado en un hospital escuela. Participaron todas las personas ingresadas en UCI General que desarrollaron NAV en 2018 y 2019. Resultados: Durante el estudio, 146 pacientes fueron diagnosticados con NAV, con una incidencia de 23,66/1000 pacientes-día en ventilación mecánica. La mediana de edad de los pacientes fue de 52,5 años y la mayoría eran hombres. Se aislaron 108 microorganismos en cultivos, siendo la mayoría bacterias gramnegativas. Las bacterias no fermentadoras fueron las más frecuentes (n=46; 42,6%), seguidas de las enterobacterias (n=42; 38,9%). Staphylococcus aureus fue el microorganismo más frecuente entre los grampositivos (n=17; 15,7%). Las bacterias multirresistentes más frecuentes fueron Acinetobacter baumannii y Enterobacter spp. Ningún microorganismo mostró resistencia a colistina y vancomicina. Los pacientes infectados con bacterias multirresistentes fueron hospitalizados por más tiempo en comparación con otros pacientes. Conclusiones: La incidencia de NAV fue alta. El conocimiento de los agentes etiológicos de la VAP y su perfil de resistencia a los antimicrobianos es fundamental para apoyar la elaboración de protocolos de tratamiento institucionales, así como para ayudar en la terapia antibiótica empírica.(AU)

Temporal evolution of polymyxin B-resistant Klebsiella pneumoniae clones recovered from blood cultures in a teaching hospital during a 7-year period.

The polymyxins have become one of the last resorts to treat serious infections caused by KPC-2-producing Klebsiella pneumoniae worldwide. However, the increase of polymyxin consumption has favored the emergence of resistance to these compounds. In this study, we observed an increase in polymyxin B resistance rates from 0 to 30.6% among 224 K. pneumoniae isolates recovered from blood cultures between 2009 and 2015. Only gentamicin, tigecycline and fosfomycin remained active against the polymyxin B-resistant K. pneumoniae (PMB-R-KPN) isolates, which were classified as extensively drug-resistant (XDR; 83.3%), multidrug-resistant (MDR; 13.9%), or pan-drug resistant (2.8%). Most PMB-R-KPN clones belonged to CC258 (ST11, ST258, ST340, and ST437). A C7/ST258 XDR clone carrying distinct resistance determinants (blaSHV-11, blaTEM-1, blaCTX-M-15, blaCTX-M-14, blaKPC-2, and rmtB-1) was introduced in 2014. Twelve of 36 PMB-R-KPN isolates showed disruption of mgrB. No mcr-1-positive isolate was found. The rapid detection of PMB-R-KPN isolates allied to implementation of effective infection control measures are of crucial importance to avoid the dissemination of high-risk PMB-R-KPN clones.

The polymyxin B-induced transcriptomic response of a clinical, multidrug-resistant Klebsiella pneumoniae involves multiple regulatory elements and intracellular targets.

BACKGROUND: The emergence of multidrug-resistant Klebsiella pneumoniae is a major public health concern. Many K. pneumoniae infections can only be treated when resorting to last-line drugs such as polymyxin B (PB). However, resistance to this antibiotic is also observed, although insufficient information is described on its mode of action as well as the mechanisms used by resistant bacteria to evade its effects. We aimed to study PB resistance and the influence of abiotic stresses in a clinical K. pneumoniae strain using whole transcriptome profiling. RESULTS: We sequenced 12 cDNA libraries of K. pneumoniae Kp13 bacteria, from two biological replicates of the original strain Kp13 (Kp13) and five derivative strains: induced high-level PB resistance in acidic pH (Kp13pH), magnesium deprivation (Kp13Mg), high concentrations of calcium (Kp13Ca) and iron (Kp13Fe), and a control condition with PB (Kp13PolB). Our results show the involvement of multiple regulatory loci that differentially respond to each condition as well as a shared gene expression response elicited by PB treatment, and indicate the participation of two-regulatory components such as ArcA-ArcB, which could be involved in re-routing the K. pneumoniae metabolism following PB treatment. Modules of co-expressed genes could be determined, which correlated to growth in acid stress and PB exposure. We hypothesize that polymyxin B induces metabolic shifts in K. pneumoniae that could relate to surviving against the action of this antibiotic. CONCLUSIONS: We obtained whole transcriptome data for K. pneumoniae under different environmental conditions and PB treatment. Our results supports the notion that the K. pneumoniae response to PB exposure goes beyond damaged membrane reconstruction and involves recruitment of multiple gene modules and intracellular targets.

Evaluation of adherence, hemagglutination, and presence of genes codifying for virulence factors of Acinetobacter baumannii causing urinary tract infection

Acinetobacter baumannii is a strictly aerobic bacterium which causes severe infections, however its pathogenic characteristics are not well defined. Thirteen A. baumannii strains isolated from urine of hospitalized and nonhospitalized patients with different ages were investigated for the presence of virulence factors. The isolates belonged to biotypes 2, 6, and 9 and were sensitive to imipenem. The majority of them showed resistance to amikacin, ceftazidime, ceftriaxone, ciprofloxacin, gentamicin, norfloxacin, and trimethoprim-sulfamethoxazole. None of A. baumannii strains presented genes codifying for 17 different virulence factors previously described in uropathogenic Escherichia coli, when tested by polymerase chain reaction (PCR). Nine isolates agglutinated human group AB erythrocytes, in presence of mannose, but none of them agglutinated group O erythrocytes. Adherence to polystyrene was observed in 7 isolates, and this result did not correlate with that obtained in hemagglutination assay. All the isolates were able to grow in iron-limiting conditions, showing that A. baumannii produces some type of siderophore. However, the genes iutA and fyuA, from iron uptake system of E. coli and Yersinia sp., respectively, were not present in the isolates, suggesting the presence of a different type of siderophore. The fimbriae of A. baumannii strains that mediates the adherence are possibly mannose-resistant, eventhough the mechanism of adherence to human epithelial cells still remains to be elucidated.

Evaluation of adherence, hemagglutination, and presence of genes codifying for virulence factors of Acinetobacter baumannii causing urinary tract infection.

Acinetobacter baumannii is a strictly aerobic bacterium which causes severe infections, however its pathogenic characteristics are not well defined. Thirteen A. baumannii strains isolated from urine of hospitalized and nonhospitalized patients with different ages were investigated for the presence of virulence factors. The isolates belonged to biotypes 2, 6, and 9 and were sensitive to imipenem. The majority of them showed resistance to amikacin, ceftazidime, ceftriaxone, ciprofloxacin, gentamicin, norfloxacin, and trimethoprim-sulfamethoxazole. None of A. baumannii strains presented genes codifying for 17 different virulence factors previously described in uropathogenic Escherichia coli, when tested by polymerase chain reaction (PCR). Nine isolates agglutinated human group AB erythrocytes, in presence of mannose, but none of them agglutinated group O erythrocytes. Adherence to polystyrene was observed in 7 isolates, and this result did not correlate with that obtained in hemagglutination assay. All the isolates were able to grow in iron-limiting conditions, showing that A. baumannii produces some type of siderophore. However, the genes iutA and fyuA, from iron uptake system of E. coli and Yersinia sp., respectively, were not present in the isolates, suggesting the presence of a different type of siderophore. The fimbriae of A. baumannii strains that mediates the adherence are possibly mannose-resistant, even though the mechanism of adherence to human epithelial cells still remains to be elucidated.

A questäo da alimentaçäo na comunidade, um estudo através da metodologia da problematizaçäo / The feed's question in the comunity: a study through the problematization's metodology

Baseado nas evidências negativas que o ensino passivotradicional apresenta, surge como alternativa de tranformaçäo pedagógica, o Projeto Especial de Ensino - PEEPIN, desenvolvido pelo Centro de Ciências de Saúde (C.C.S.) - UEL, que elabora o processo de aprendizagem a partir da Metodologia da Problematizaçäo. Este artigo visa a descriçäo de um grupo de estudo (e trabalho) deste Projeto. Deste modo, o tema alimentaçäo foi abordado como maneira do nosso grupo entrar em contato com a realidade e a partir dos problemas apresentados pela populaçäo, desenvolvermos hipóteses e métodos de soluçäo para estes. O principal objetivo do grupo era proporcionar melhorias nos padröes alimentares através da conscientizaçäo da comunidade, com uma dieta que interfira o mínimo possível nos hábitos alimentares da populaçäo. Como objetivos indiretos, destacamos a integraçäo e desenvolvimento em equipe multidisciplinar, o amadurecimento ético e humanístico e o despertar do espírito crítico responsável logo no início da formaçäo profissional