RESUMO Introdução: Estafilococos coagulase-negativos (ECN) estão entre os principais colonizantes de pele e mucosas, atuando como comensais. Apesar de apresentarem baixa virulência, podem causar infecções graves, principalmente quando são utilizados dispositivos invasivos, como cateteres. Como têm grande capacidade de formar biofilme, conseguem atingir rapidamente a corrente sanguínea, o que pode levar à septicemia. Objetivo: O objetivo principal foi comparar a identificação dos ECN entre duas metodologias automatizadas: fenotípica (VITEK® 2 Compact, bioMérieux) e espectrometria de massa (MALDI-TOF VITEK® MS, bioMérieux). Materiais e método: Foram analisados 133 isolados de ECN provenientes de amostras de hemoculturas, no período de setembro de 2015 a maio de 2016. Resultados: Todos os 133 isolados foram identificados no VITEK® 2 Compact como ECN, enquanto o VITEK MS não identificou sete amostras; houve incerteza entre três espécies em um isolado. Os dois equipamentos tiveram concordância de 92,8% (117/126), dos quais foram 56 Staphylococcus epidermidis, 34 Staphylococcus hominis ssp. hominis, 15 Staphylococcus haemolyticus, 10 Staphylococcus capitis, um Staphylococcus cohnii ssp. urealyticus e um Staphylococcus sciuri. Houve discordância em uma identificação de S. lugdunensis e S. aureus. Conclusão: Por meio da análise entre os dois equipamentos e com base em artigos científicos que comparam os métodos envolvidos neste estudo, foi possível observar a grande similaridade bioquímica entre as espécies de ECN, sendo esta a principal limitação do método fenotípico. O equipamento VITEK MS apresentou alta discriminação entre as espécies quando comparado com o método gold standard, além da facilidade e da agilidade da técnica.

ABSTRACT Introduction: In most clinical laboratories, coagulase-negative staphylococci (CNS) are classified through their biochemical characteristics using traditional and/or automated phenotypic methods. However, identification by phenotypic method is a great challenge despite the improvement in identification by automated systems in recent years. Objective: The main objective was to compare the identification of CNS between two automated methods: phenotypic (VITEK® 2 Compact, bioMérieux) and mass spectrometry (MALDI-TOF VITEK® MS, bioMérieux). Materials and method: 133 CNS isolates from whole blood samples from September 2015 to May 2016 were analyzed. Results: All the 133 isolates were identified by VITEK® 2 Compact as CNS, whereas VITEK MS did not identify seven, and there was uncertainty among three species in one isolate. The two devices had a concordance of 92.8% (117/126) of which: 56 Staphylococcus epidermidis, 34 Staphylococcus hominis ssp. hominis, 15 Staphylococcus haemolyticus, 10 Staphylococcus capitis, one Staphylococcus cohnii ssp. urealyticus and one Staphylococcus sciuri. There was disagreement in identification of S. lugdunensis and S. aureus. Conclusion: Through the analysis between the two devices and based on scientific articles comparing the methods involved in the study, it was possible to observe the great biochemical similarity among the coagulase-negative staphylococci species, this being the main limitation of the phenotypic method. The VITEK MS equipment showed high discrimination between species when compared to the gold standard method, besides being rapid and easy to use.

OBJETIVO: verificar a prevalência de estreptococo do grupo B (EGB) em gestantes no terceiro trimestre da gravidez e explorar os fatores potencialmente associados à colonização. MÉTODOS: uma amostra de 273 gestantes no terceiro trimestre da gravidez, provenientes do ambulatório de pré-natal do Hospital Universitário do Sul do Brasil, foi investigada. Culturas de amostra vaginal e anorretal foram obtidas e inoculadas em meio seletivo de Todd-Hewitt suplementado com 10 µg/ml de colistina e 15 µg/ml de ácido nalidíxico e posteriormente subcultivadas em ágar sangue de carneiro desfibrinado. Todas as colônias suspeitas foram submetidas ao teste de aglutinação para detecção do antígeno específico do grupo B. O teste de Camp foi utilizado para identificação do EGB das variedades não hemolíticas. Analisaram-se também os dados demográficos, socioeconômicos, reprodutivos e clínico-obstétricos. A razão de prevalência (RP) foi utilizada como medida de risco. Considerou-se como significante o intervalo de confiança no nível de 95% (alfa=0,05). RESULTADOS: a prevalência de colonização pelo EGB foi de 21,6% (59), sendo que 9,9% (27) das gestantes tiveram positividade em ambos os sítios, 6,95% (19) foram positivas somente no sítio vaginal e 4,75% (13) da amostra tiveram positividade apenas no sítio anal. A prevalência de EGB foi ligeiramente mais alta nas gestantes com idade inferior a 20 anos, naquelas com menor escolaridade e nas gestantes primíparas, e o dobro entre aquelas que não relataram aborto espontâneo, porém sem significância estatística. Não foi encontrada diferença na prevalência de EGB de acordo com história de doenças sexualmente transmissíveis e tabagismo. Quando os dados foram analisados conjuntamente, os fatores detectados como potencialmente associados à colonização pelo EGB foram: primíparas com mais de 30 anos (RP=1,55) e mulheres com mais de um parceiro sexual e freqüência de atividade sexual aumentada (55,6 vs 20,5%; p<0,05). CONCLUSÃO: confirma-se a necessidade rotineira de cultura para EGB em ambos os sítios (vaginal e anal) de todas as gestantes no terceiro trimestre de gestação.

PURPOSE: to determine the prevalence of group B Streptococcus (GBS) in pregnant women in the third trimester of pregnancy and explore the factors potentially associated with colonization. METHODS: a sample of 273 pregnant women in the third trimester of pregnancy, from the prenatal care center in Southern Brasil, was investigated. Vaginal and anorectal samples were collected and innoculated in Todd-Hewitt selective broth supplemented with 10 µg/mL colistin and 15 µg/mL nalidixic acid and afterwards cultured on defibrinated sheep blood agar plates. All suspected colonies were submitted to the agglutination test for detection of the specific group B antigen. The Camp test was used for GBS identification in non-hemolytic varieties. Demographic, socioeconomic, reproductive, and clinico-obstetric data were also analyzed. Prevalence ratio (PR) was used as risk measurement. Confidence interval was considered significant at the level of 95% (alpha=0.05). RESULTS: prevalence of Streptococcus (GBS) colonization amounted to 21.6% (59), 9.9% (27) of pregnant women showing positivity in both sites; vaginal site colonization was found in 6.95% (19) of the women and 4.75% (13) of the samples showed positivity only in the anal site. GBS prevalence was slightly higher in pregnant women under 20 years, in those with less schooling and in primiparae and was twice as high among those who did not reported spontaneous abortion, but with no statistical significance. No difference was found in GBS prevalence according to the history of sexually transmittted diseases and tabagism. When analyzed together, the factors detected as potentially associated with colonization by GBS were: primiparae over 30 years (PR=1.55) and women with more than one sexual partner and increased frequency of sexual activity (p<0.05) (55,6 vs 20.5%; p<0.05). No difference regarding prevalence was found to exist in relation to the history of sexually transmitted diseases, previous spontaneous abortion and tabagism. CONCLUSION: these results confirm the need for routine collection for GBS culture from both sites (vaginal and anal) in all pregnant women in the third trimester of pregnancy.

BACKGROUND: Pathogen frequency and resistance patterns may vary significantly from country to country and also in different hospitals within a country. Thus, regional surveillance programs are essential to guide empirical therapy and infection control measures. METHODS: Rank order of occurrence and antimicrobial susceptibility of pathogenic species causing bloodstream infections (BSI), lower respiratory tract infections (LRTI), wound or skin and soft tissue infections (WSSTI), and urinary tract infections (UTI) in hospitalized patients were determined by collecting consecutive isolates over a specified period of time, as part of the SENTRY Antimicrobial Resistance Surveillance Program (SENTRY). All isolates were tested by reference broth microdilution. RESULTS AND CONCLUSIONS: A total of 3,728 bacterial strains were obtained from January, 1997, to December, 1999, from 12 Brazilian hospitals located in 4 states. The largest number of isolates were obtained from patients with BSI (2,008), followed by LRTI (822 cases), UTI (468 cases), and WSSTI (430 cases). Staphylococcus aureus was the most frequently isolated pathogen in general (22.8% - 852 isolates), followed by E. coli (13.8% - 516 cases) and Pseudomonas aeruginosa (13.3% - 496 cases). Staphylococcus aureus was also the most common species isolated from BSI (23.6%) and WSSTI (45.8%), and P. aeruginosa was the most frequent species isolated from patients with LRTI (29.4%). The main bacterial resistance problems found in this study were: imipenem resistance among P. aeruginosa (69.8% susceptibility) and Acinetobacter spp. (88.1% susceptibility); ESBL production among K. pneumoniae (48.4%) and E. coli (8.9%); resistance to third generation cephalosporins among Enterobacter spp. (68.1% susceptible to ceftazidime) and oxacillin resistance among S. aureus (34.0%) and coagulase negative staphylococci (80.1%). Only the carbapenems (88.1% to 89.3% susceptibility) showed reasonable activity against the Acinetobacter spp. isolates evaluated.