RESUMO Introdução: O complexo Acinetobacter calcoaceticus-baumannii (ABC) inclui cinco espécies, sendo A. baumannii a mais importante clinicamente por carrear muitos mecanismos de resistência aos carbapenêmicos, sobretudo as oxacilinases. Objetivos: Os objetivos deste estudo foram identificar as espécies do complexo ABC, avaliar o perfil de suscetibilidade e investigar a presença de oxacilinases em isolados resistentes aos carbapenêmicos provenientes de quatro estados brasileiros. Métodos: No período do estudo, foram coletados 92 isolados do Rio Grande do Sul (RS), do Rio de Janeiro (RJ), do Paraná (PR) e de São Paulo (SP). Os isolados foram identificados por matrix-assisted laser desorption ionization-time of fight mass spectrometry (MALDI-TOF MS) e sequenciamento do gene gyrB. A avaliação da suscetibilidade foi realizada por disco-difusão e microdiluição de caldo. A presença de oxacilinases foi realizada por reação em cadeia da polimerase (PCR) multiplex in house. Resultados: Noventa e um (99%) isolados foram identificados como A. baumannii por MALDI-TOF e pelo sequenciamento. A maioria dos isolados (56; 61%) apresentou resistência aos seis agentes antimicrobianos testados. Três isolados foram resistentes à polimixina B [concentração inibitória mínima (CIM) ≥ 4 µg/ml). Oitenta (87%) isolados foram positivos para OXA-23 e 12, (13%) para OXA-24. Conclusão: Nossos resultados confirmam a disseminação do gene blaOXA-23 no Brasil e sugerem a recente emergência e disseminação do gene blaOXA-24, uma vez que ele foi identificado em três dos quatro estados amostrados.

ABSTRACT Introduction: The Acinetobacter calcoaceticus-baumannii (ABC) complex includes five species, and the A. baumannii is the most important of them because it carries mechanisms of carbapenems resistance, especially the oxacillinases. Objectives: The objectives of this study were to identify the species of the ABC complex, to evaluate the susceptibility profile and to investigate the presence of oxacillinases in carbapenems-resistant isolates from four Brazilian States. Methods: In the study period, 92 isolates from Rio Grande do Sul (RS), Rio de Janeiro (RJ), Paraná (PR) and São Paulo (SP) were collected. The isolates were identified by matrix-assisted laser desorption ionization-time of fight mass spectrometry (MALDI-TOF MS) and sequencing of gyrB gene. Evaluation of susceptibility was performed by disk diffusion and broth microdilution. The presence of oxacillinases was performed by in-house multiplex polymerase chain reaction (PCR). Results: Ninety-one (99%) isolates were identified as A. baumannii by MALDI-TOF and sequencing. The majority of isolates (56; 61%) showed resistance to the six antimicrobial agents tested. Three isolates were resistant to polymyxin B [minimum inhibitory concentration (MIC) ≥ 4 µg/ml). Eighty (87%) isolates were positive to OXA-23-like, and twelve (13%) isolates to OXA-24-like. Conclusion: Our findings confirm the knowledge about the dissemination of the blaOXA-23 gene in Brazil and suggest the recent emergence and spread of blaOXA-24 gene, since it was identified in three of the four sampled states.

BACKGROUND Mycobacterium abscessus complex (MABC) includes species with high resistance rates among mycobacterial pathogens. In fact, MABC infections may not respond to clarithromycin treatment, which has historically been very effective against MABC infection. Molecular markers have been proposed to detect both acquired (rrl polymorphisms) and inducible (erm(41) polymorphisms) clarithromycin resistance in MABC isolates. OBJECTIVES This study aimed to evaluate the susceptibility profile and molecular markers of clarithromycin resistance in MABC. METHODS The clarithromycin susceptibility profile was determined by broth microdilution with reads on days 3, 5, 7 and 14. Mutations in the rrl and erm(41) genes were evaluated by polymerase chain reaction (PCR) using specific primers, followed by sequencing. FINDINGS A total of 14 M. abscessus subsp. abscessus isolates and 28 M. abscessus subsp. massiliense isolates were evaluated, and clarithromycin resistance was observed in all isolates for up to three days of incubation. None of the 42 isolates exhibited a point mutation in the rrl gene, while all the isolates had a T28 polymorphism in the erm(41) gene. Moreover, all 28 M. abscessus subsp. massiliense isolates had a deletion in the erm(41) gene. MAIN CONCLUSIONS While all the MABC isolates exhibited acquired clarithromycin resistance, no isolates exhibited a point mutation in the rrl gene in this study. The M. abscessus subsp. massiliense isolates demonstrated clarithromycin resistance, which is an uncommon phenotype. The molecular data for the rrl and erm(41) genes were not consistent with the phenotypic test results of clarithromycin susceptibility, indicating a lack of correlation between molecular clarithromycin resistance markers for both acquired and inducible resistance.

Abstract INTRODUCTION: Group B Streptococcus (GBS), a source of neonatal infection, colonizes the gastrointestinal and genitourinary tracts of pregnant women. Routine screening for maternal GBS in late pregnancy and consequent intrapartum antibiotic prophylaxis have reduced the incidence of early-onset GBS neonatal infection. The aim of this study was to evaluate the performance of PCR, compared to culture (gold standard), in GBS colonization screening of pregnant women, and to establish the prevalence of GBS colonization among this population. METHODS: Vaginal introitus and perianal samples were collected from 204 pregnant women, between the 35th and 37th weeks of pregnancy, at the Obstetrics and Gynecology Unit of the University of Caxias do Sul General Hospital between June 2008 and September 2009. All samples were cultured after enrichment in a selective medium and then assayed by culture and PCR methods. RESULTS: The culture and PCR methods yielded detection rates of vaginal/perianal GBS colonization of 22.5% and 26%, respectively (sensitivity 100%; specificity 95.6%; positive and negative predictive values 86.8% and 100%, respectively). A higher prevalence of GBS colonization was detected in the combined vaginal and perianal samples by both culture and PCR assay analyses. CONCLUSIONS: PCR is a faster and more efficient method for GBS screening, allowing for optimal identification of women who should receive intrapartum antibiotic prophylaxis to prevent newborn infection.

Abstract Acinetobacter baumannii is widely recognized as an important pathogen associated with nosocomial infections. The treatment of these infections is often difficult due to the acquisition of resistance genes. A. baumannii presents a high genetic plasticity which allows the accumulation of these resistance determinants leading to multidrug resistance. It is highlighted the importance of the horizontal transfer of resistance genes, through mobile genetic elements and its relationship with increased incidence of multidrug resistant A. baumannii in hospitals. Considering that resistance to carbapenems is very important from the clinical and epidemiological point of view, the aim of this article is to present an overview of the current knowledge about genetic elements related to carbapenem resistance in A. baumannii such as integrons, transposons, resistance islands and insertion sequences.

Introduction This study reports the pediatric epidemiology of respiratory syncytial virus (RSV), influenza (IF), parainfluenza (PIV), and adenovirus (ADV) at Hospital de Clínicas de Porto Alegre. Methods Cases of infection, hospitalizations in intensive care units (ICUs), nosocomial infections, and lethality rates were collected from 2007 to 2010. Results RSV accounted for most nosocomial infections. Intensive care units admission rates for ADV and RSV infections were highest in 2007 and 2010. During 2008-2009, H1N1 and ADV had the highest ICU admission rates. ADV had the highest fatality rate during 2007-2009. Conclusions Each virus exhibited distinct behavior, causing hospitalization, outbreaks, or lethality.

INTRODUÇÃO: Hospitais no mundo todo têm apresentado surtos de Acinetobacter sp. multirresistentes. A disseminação destes isolados com uma variedade cada vez maior de genes de resistência torna difícil o tratamento destas infecções e seu controle dentro do ambiente hospitalar. Este trabalho teve como objetivo avaliar a ocorrência e disseminação de isolados de Acinetobacter sp. multirresistentes e identificar genes de resistência adquirida. MÉTODOS: Foram avaliados 274 isolados clínicos de Acinetobacter sp. obtidos de cinco hospitais da Cidade de Porto Alegre, RS, Brasil. Avaliamos o perfil de suscetibilidade a antimicrobianos, genes de resistência adquirida das classes B e D de Ambler e realizamos a tipificação molecular dos isolados utilizando a técnica de enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). RESULTADOS: Encontramos uma alta (68%) porcentagem de isolados de Acinetobacter sp. multirresistentes e 69% dos isolados apresentaram resistência aos carbapenêmicos. Foram identificados 84% de isolados pertencentes a espécie A. baumannii, pois apresentaram o gene blaOXA-51. Em 62% dos isolados, foi detectado o gene blaOXA-23, sendo que 98% destes isolados foram resistentes aos carbapenêmicos. Através da tipificação molecular pela técnica de ERIC-PCR identificamos clones de Acinetobacter sp. disseminados entre quatro dos hospitais analisados e nos anos de 2006 e 2007. CONCLUSÕES: Os dados obtidos indicam a disseminação de isolados de Acinetobacter sp. entre hospitais assim como sua permanência no ambiente hospitalar após um ano.

INTRODUCTION: Hospitals around the world have presented multiresistant Acinetobacter sp. outbreaks. The spread of these isolates that harbor an increasing variety of resistance genes makes the treatment of these infections and their control within the hospital environment more difficult. This study aimed to evaluate the occurrence and dissemination of Acinetobacter sp. multiresistant isolates and to identify acquired resistance genes. METHODS: We analyzed 274 clinical isolates of Acinetobacter sp. from five hospitals in Porto Alegre, RS, Brazil. We evaluated the susceptibility to antimicrobial, acquired resistance genes from Ambler's classes B and D, and performed molecular typing of the isolates using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) technique. RESULTS: A high (68%) percentage of multiresistant isolates of Acinetobacter sp. was observed, and 69% were resistant to carbapenems. We identified 84% of isolates belonging to species A. baumannii because they presented the gene blaOXA-51. The gene blaOXA-23 was detected in 62% of the isolates, and among these, 98% were resistant to carbapenems. Using the ERIC-PCR technique, we identified clones of Acinetobacter sp. spread among the four hospitals analyzed during the sampling period. CONCLUSIONS: The data indicate the dissemination of Acinetobacter sp. isolates among hospitals and their permanence in the hospital after one year.

INTRODUÇÃO: Staphylococcus aureus resistentes à meticilina associados à comunidade (CA-MRSA) têm emergido como patógeno em indivíduos sem os tradicionais fatores de risco. MATERIAIS E MÉTODOS: Carreamento nasal de MRSA foi avaliado em indivíduos atendidos em unidade básica de saúde. RESULTADOS: 336 indivíduos foram incluídos: 136 foram testados somente para MRSA e 200 para qualquer S. aureus. Nenhum MRSA foi encontrado nos 336 indivíduos e 23 (11.5%) de 200 eram colonizados por S. aureus. DISCUSSÃO: Baixas taxas de prevalência têm sido encontradas em indivíduos não-hospitalizados, entretanto a vigilância de MRSA é encorajada para o monitoramento da epidemiologia clínica e molecular do CA- MRSA.

INTRODUCTION: Community-associated methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a pathogen in individuals without traditional risk factors. MATERIAL AND METHODS: MRSA nasal carriage was assessed in individuals consulting at a Primary Health Unit in Brazil. RESULTS: A total of 336 individuals were included: 136 were tested only for MRSA and 200 for any S. aureus. No MRSA was found among the 336 individuals and 23 (11.5%) of 200 were colonized by S. aureus. DISCUSSION: Low prevalence rates have been found in non-hospitalized individuals, but MRSA surveillance should be encouraged to monitor clinical and molecular epidemiology of CA- MRSA.

Streptococcus agalactiae or group B Streptococcus (GBS) is one of the most important causal agents of serious neonatal infections. Numerous assays have been evaluated for GBS screening in order to validate a fast and efficient method. The aim of this study was to compare the culture technique (established as the gold standard) with the molecular method of polymerase chain reaction (PCR) with specific primers (atr gene). Two hundred and sixty-three samples were analyzed. Vaginal samples were collected, according to the Centers for Disease Control and Prevention (CDC) recommendations, from women over 35 weeks of pregnancy at Hospital de Clínicas de Porto Alegre (HCPA). Two different extraction methods were tested in all samples collected. PCR technique yielded 71 (26.99%) positive results. Sensitivity and specificity for PCR were 100% and 86.88%, respectively. PCR demonstrated a shorter turnaround time than the culture. The molecular methodology proved to be a useful screening for GBS, allowing effective treatment to be initiated in shorter time to prevent newborn infection.

Biofilm production is an important mechanism that allows microbes to escape host defences and antimicrobial therapy. Vancomycin has been used largely for the treatment of methicillin-resistant staphylococcal infections. Here, we determined the minimal inhibitory concentration (MIC) and minimal biofilm eradication concentration (MBEC) for 82 Staphylococcus species isolated from central venous catheters (CVC). Our results showed that the 41 strong and moderate-biofilm-producing isolates presented a higher MBEC/MIC ratio for vancomycin than the 24 weak-biofilm-producing isolates, illustrating the importance of biofilm production ability and the difficulty in treating biofilm-related infections. The MBEC was significantly higher in moderate-biofilm-producing isolates than in weak-biofilm-producing isolates (p < 0.001) and in strong-biofilm-producing isolates than in weak-biofilm-producing isolates (p = 0.001). The correlation between the MIC and the MBEC was poor. Based on our results, we recommend that bacterial biofilms be suspected in all cases of CVC infection.

INTRODUCTION: Resistance to macrolides, lincosamides and streptogramins B (MLS B antibiotics) in staphylococci may be due to modification in ribosomal target methylase encoded by erm genes. The expression of MLS B resistance lead to three phenotypes, namely constitutive resistance (cMLS B), inducible resistance (iMLS B), and resistance only to macrolides and streptogramins B (MS B). The iMLS B resistance is the most difficult to detect in the clinical laboratory. OBJECTIVE: This study investigated the expression of MLS B resistance and the prevalence of the erm genes among 152 clinical isolates of Staphylococcus aureus and coagulase-negative Staphylococcus (CNS) from Hospital de Clínicas de Porto Alegre. METHODS: Primary MLS B resistance was detected by the disk diffusion method. Isolates with iMLS B phenotype were tested by double-disk induction method. All isolates were tested by a genotypic assay, PCR with specific primers. RESULTS: A total of 46.7% of staphylococci were positive for cMLS B; 3.3% for iMLS B and 3.3% for MS B. One or more erm genes were present in 50.1% of isolates. The gene ermA was detected in 49 isolates, ermC in 29 and ermB in 3. CONCLUSION: The prevalence of the ermA, ermB and ermC genes were 29.6%, 17.1% and 0.66% respectively, and constitutive resistance was the most frequent as compared to the other two phenotypes.

This study evaluated the clonal spread of carbapenem-resistant P. aeruginosa producing SPM-1 type metallo-β-lactamase (MBL), at the university hospital of Florianópolis, Santa Catarina, Brazil, compared to an epidemic clone previously reported, as well as strains collected in other three Brazilian states. Among the isolates, 17 (62%) were clonal and highly related to strains from other regions of Brazil. Six clonal strains harbored the blaSPM-1 gene. The finding of a unique SPM-1 producer clone suggests that its dissemination has contributed to the high resistance to carbapenems in Brazilian hospitals

RACIONAL: Infecções são a causa principal de morbimortalidade em pacientes submetidos a transplantes hepáticos. OBJETIVO: Avaliar as principais características destas infecções em pacientes de um hospital universitário do sul do Brasil. MÉTODO: Uma coorte retrospectiva foi conduzida com os 55 pacientes transplantados hepáticos adultos cuja cirurgia foi realizada entre 1996 e 2000 no Hospital de Clínicas de Porto Alegre, RS, todos aos eventos infecciosos que ocorreram nesta população foram registrados. RESULTADOS: Uma ou mais infecções (média 2,1 episódios) foram diagnosticadas em 47 pacientes, o período de maior ocorrência destas foi o primeiro mês após a cirurgia. As infecções mais comuns foram: bacteremias, infecções intra-abdominais e pneumonias, a etiologia mais freqüente foi bacteriana, sendo os germes mais comuns os estafilicocos (em particular o S. aureus) e a E. coli. A taxa de mortalidade associada a infecções foi elevada: 17 óbitos de todos observados na coorte (27 no total). Os fatores de risco para infecção estatisticamente significantes foram: reoperação, diabetes, estenose de via biliar e classificação de Child-Pugh elevada. CONCLUSÃO: As infecções continuam sendo grave ameaça aos pacientes transplantados hepáticos e intenso esforço, que envolve o conhecimento da epidemiologia microbiológica, pesquisa e acompanhamento dos pacientes deve ser empregado, para prevenir e tratar de forma adequada estas complicações.

BACKGROUND: Infections after liver transplantations are the most important cause of morbi-mortality. In this study, we assessed the main characteristics of these infections in a southern Brazilian university hospital. METHODS: We conducted a retrospective cohort with 55 patients who underwent orthotopic liver transplantation between 1996 and 2000 in the "Hospital de Clínicas de Porto Alegre", Porto Alegre, RS, Brazil, to characterize the infections that occurred in the group. RESULTS: One or more infections (average 2.10) were diagnosed in 47 patients, especially during the first month after transplantation. The most common were bacteremia, intra-abdominal infections and pneumonia, predominantly with bacteria, especially Staphylococcus sp (and particularly S. aureus) and E. coli. The mortality rate attributed to infections was high: 17 cases of all deaths (total 27 deaths). Significant risk factors for infections included reoperation, diabetes, biliary stenosis and higher Child-Pugh scores. CONCLUSION: Infections remain a severe threat in liver transplant patients, and special efforts should be made to prevent and manage them correctly.

Descrevemos a ocorrência dos genes de metalo-beta-lactamases (MBL) blaSPM-1 e blaIMP-1 em isolados clínicos de Pseudomonas aeruginosa resistentes ao imipenem e/ou ceftazidima obtidos em três hospitais universitários de Porto Alegre, Brasil. A produção de MBL foi observada através de técnica fenotípica e os genes foram detectados pelo método de PCR.

We described the ocurrence of metallo-beta-lactamases (MBL) genes blaSPM-1 and blaIMP-1 in clinical isolates of Pseudomonas aeruginosa resistant to imipenem and/or ceftazidime obtained from three universitary hospitals in the city of Porto Alegre, Brazil. The MBL production was screened by phenotypic test and the genes were detected by PCR.

Bloodstream infections caused by yeast, Candida spp, are quite important clinically and epidemiologically due to a high mortality rate and an increasing number of non-albicans species with a more resistant (differentiated susceptibility) profile. We examined species prevalence and susceptibility profile for fluconazole and the risk for nosocomial infections by Candida spp at the Hospital de Clínicas de Porto Alegre, a general tertiary care hospital in southern Brazilian, through a retrospective study, beginning with positive cultures of hospitalized patients. The distribution by species in 131 documented episodes was as follows: Candida albicans (45%), C. parapsilosis (24.4%), C. tropicalis (15.3%), C. glabrata (6.9%), C. krusei (4.6%) and 3.8% other species (C. pelicullosa, C. guilliermondii, C. lusitaniae and C. kefyr). The vast majority of samples (121- 92.4%) were susceptible to fluconazole; the resistant or dose-dependent sensitive samples included only C. krusei and C. glabrata. Blood diseases (leukemia, lymphoma), or neoplasias (solid tumors), were found in 35.0% of the candidemia episodes. We noted the previous use of antibiotics in 128 (97.7%) patients, with 79.7% using three or more antibiotics before the candidemia episode. Other risk factors included a central venous catheter in 94 (71.8%) and abdominal surgery in 32 (24.4%) patients. The overall mortality rate was 51.9%, which varied according to the underlying disease. We found that C. albicans was the most prevalent species, although the non-albicans species predominated. However, in vitro resistance to fluconazole was detected only among the species (C. glabrata and C. krusei) that tend to be resistant to the azolic compounds. Previous use of antibiotic and the use of a central venous catheter were the main risk factors among patients with candidemia.