Involvement of lipid microdomains in human endothelial cells infected by Streptococcus agalactiae type III belonging to the hypervirulent ST-17

BACKGROUND Streptococcus agalactiae capsular type III strains are a leading cause of invasive neonatal infections. Many pathogens have developed mechanisms to escape from host defense response using the host membrane microdomain machinery. Lipid rafts play an important role in a variety of cellular functions and the benefit provided by interaction with lipid rafts can vary from one pathogen to another. OBJECTIVES This study aims to evaluate the involvement of membrane microdomains during infection of human endothelial cell by S. agalactiae. METHODS The effects of cholesterol depletion and PI3K/AKT signaling pathway activation during S. agalactiae-human umbilical vein endothelial cells (HUVEC) interaction were analysed by pre-treatment with methyl-β-cyclodextrin (MβCD) or LY294002 inhibitors, immunofluorescence and immunoblot analysis. The involvement of lipid rafts was analysed by colocalisation of bacteria with flotillin-1 and caveolin-1 using fluorescence confocal microscopy. FINDINGS In this work, we demonstrated the importance of the integrity of lipid rafts microdomains and activation of PI3K/Akt pathway during invasion of S. agalactiae strain to HUVEC cells. Our results suggest the involvement of flotillin-1 and caveolin-1 during the invasion of S. agalactiae strain in HUVEC cells. CONCLUSIONS The collection of our results suggests that lipid microdomain affects the interaction of S. agalactiae type III belonging to the hypervirulent ST-17 with HUVEC cells through PI3K/Akt signaling pathway.

Susceptibility of Streptococcus agalactiae to erythromycin and clindamycin in pregnant women in the prenatal screening

Introduction: Group B streptococcus (GBS), or Streptococcus agalactiae, is a bacterium found in normal human microbiota. However, it may cause neonatal pneumonia, sepsis, and meningitis. Genital colonization in pregnant women is associated with a higher risk of preterm birth. The treatment of choice is antibiotic therapy with beta-lactams, but in the case of multidrug-resistance, erythromycin and clindamycin can be used. Methods: This study evaluated bacterial cultures in the period from 2014 to 2015 from a group of 29,875 pregnant women. GBS colonization and resistance to erythromycin and clindamycin were investigated. Results: Positive cultures were found in 26.8% and 26.1% of the samples in 2014 and 2015, respectively. Levels of resistance to erythromycin and clindamycin were, respectively, 2.4% and 5.5% in 2014 and 3.2% and 6.5% in 2015. Conclusion: The investigation of GBS colonization and the evaluation of GBS resistance to erythromycin and clindamycin are of extreme relevance, given the increasing incidence of bacterial resistance, risks of preterm birth. (AU)

Estudo retrospectivo sobre a prevalência de Streptococcus agalactiae em gestantes em um município do interior do Rio Grande do Sul, Brasil / Retrospective study on the prevalence of Streptococcus agalactiae among pregnant from a municipality in the state of Rio Grande do Sul, Brazil

Introdução: O Streptococcus agalactiae, também conhecido como estreptococo do grupo B (EGB), é uma bactéria pertencente à microbiota de seres humanos e encontra-se aderido às membranas das mucosas, colonizando principalmente os tratos gastrointestinal e geniturinário. Métodos: Trata-se de um estudo retrospectivo que envolveu a coleta de dados do Laboratório de Análises Clínicas de Veranópolis (RS), no período de abril de 2014 a fevereiro de 2017. Resultados: No período estudado, realizaram o exame no referido laboratório 109 gestantes que se encontravam a partir da 27ª semana de gestação, das quais 92 (84,4%) apresentaram resultado negativo e 17 (15,6%) apresentaram resultado positivo para S. agalactiae. Conclusão: Os resultados demonstram a importância de realizar a pesquisa de S. agalactiae antes do parto, para manter o recém-nascido e a mãe em segurança e sem complicações. (AU)

Introduction: Streptococcus agalactiae, also known as group B streptococcus (GBS), is a bacterium from the human microbiota that adheres to the mucous membranes, mainly colonizing the gastrointestinal and genitourinary tracts. Methods: This is a retrospective study involving the collection of data from the Laboratory of Clinical Analyzes of Veranópolis (RS), from April 2014 to February 2017. Results: During the study period, 109 pregnant women at the 27 weeks gestation or more were evaluated for S. agalactiae at the above mentioned laboratory, of which 92 (84.4%) were negative and 17 (15.6%) were positive for this bacteria. Conclusion: The results demonstrate the importance of performing screening for S. agalactiae before delivery to keep the newborn and the mother safe and without complications. (AU)

Transferência passiva de soro hiperimune anti-Streptococcus agalactiae e seu efeito profilático em tilápias-do-nilo infectadas experimentalmente: sobrevivência e títulos de anticorpos / Passive transfer of hyperimmune serum anti Streptococcus agalactiae and its prophylactic effect on Nile tilapia experimentally infected

A bactéria Streptococcus agalactiae é um potente agente causador de surtos por doenças bacterianas em peixes. O estresse provocado pelo manejo zootécnico e pela má qualidade ambiental torna a tilápia susceptível às infecções por essa bactéria. O objetivo do presente trabalho foi avaliar a resistência de tilápias-do-nilo imunizadas com soro hiperimune anti-S. agalactiae, posteriormente desafiadas com cepa homóloga da mesma bactéria. Após determinação da DL 50 de S. agalactiae, 36 tilápias foram distribuídas em quatro aquários, dois para o grupo controle e dois para inoculação celomática para produção de anticorpos anti-S. agalactiae. No 21° e 28° dias, foi coletado sangue para obtenção de soro hiperimune utilizado na transferência passiva. Em seguida, 30 tilápias foram distribuídas em três aquários e submetidas a três tratamentos: GI: controle; GII: imunizadas com o soro inativado; GIII: imunizadas com soro ativo...

The Streptococcus agalactiae bacteria is a potent agent which causes outbreaks of bacterial diseases in fish. The stress caused by management and poor environmental quality makes tilapia susceptible to infections, including by bacterium. The aim of this study was to evaluate the resistance of the Nile tilapia immunized with hyperimmune serum against S. agalactiae subsequently challenged with homologous strain of the same bacteria. After determining the DL 50 of S. agalactiae, 36 tilapias were distributed in 4 aquariums, 2 for the control group and 2 for the group via coelomic, inoculated with the DL 50 for anti-S. agalactiae antibodies production. On the 21st and 28th day blood was collected for the obtainment of hiperimmune serum used in passive transference. Then, 30 tilapias were distributed in 3 aquariums submitted to 3 treatments (GI: control; GII: immunized with inactivated-serum; GIII: immunized with non-inactivated serum)...

Influence of temperature on streptococcus agalactiae infection in Nile tilapia / Influência da temperatura na infecção de tilápias do Nilo por Streptococcus agalactiae

Environmental changes affect fish homeostasis, turning them more susceptible to diseases. In Brazil, outbreaks of Streptococcus agalactiae infection have been reported in Nile tilapia when they are outside of their thermal comfort zone. This investigation evaluated mortality rate and which were the most infected organs at temperatures that naturally occurred in southern of Brazil. Forty Nile tilapia (Oreochromis niloticus) were infected with S. agalactiae and distributed in four groups (n=10) and each group was exposed to a different temperature: G1: 24°C, G2: 26°C, G3: 28°C, and G4: 32°C. Fish were monitored for 10 days. In this period, fish that presented irreversible clinical signs were sacrificed and samples of brain, liver, and kidney were collected for bacteriological and molecular analysis. Signs compatible with a streptococcal infection were observed in all groups. Highest mortality rates occurred at 24°C and 32°C. The brain was the most affected organ with the highest percentage of isolation of S. agalactiae by both methods of diagnosis. The results suggest that, as in mammals, temperatures that are further away from the comfort zone influence fish homeostasis, increasing susceptibility to bacterial infections.

Mudanças ambientais afetam a homeostase dos peixes, tornando-os mais suscetíveis a doenças. No Brasil, têm sido relatados surtos de infecção por Streptococcus agalactiae em tilápia do Nilo, principalmente quando se encontram fora da zona de conforto térmico. No presente trabalho, foi avaliada a taxa de mortalidade e determinado quais foram os órgãos mais afetados por essa bactéria em temperaturas que ocorrem naturalmente no Sul do Brasil. Quarenta tilápias-do-nilo (Oreochromis niloticus) foram infectadas por Streptococcus agalactiae e distribuídas em quatro grupos (n = 10), cada um deles submetidos a diferentes temperaturas: G1: 24°C, G2: 26°C, G3: 28°C e G4: 32°C. Os peixes foram monitorados durante 10 dias. Os peixes com sinais clínicos irreversíveis foram sacrificados e coletadas amostras de cérebro, fígado e rins para análise bacteriológica e molecular. Foram observados sinais compatíveis com infecção estreptocócica em todos os grupos. A taxa de mortalidade mais elevada ocorreu nos grupos mantidos nas temperaturas de 24°C e 32°C. O cérebro foi o órgão mais afetado, com a maior percentagem de isolamento de S. agalactiae pelos dois métodos de diagnóstico. Os resultados sugerem que, tal como nos mamíferos, temperaturas que estão mais afastadas da zona de conforto afetam significativamente a homeostase dos peixes, aumentando a sua susceptibilidade para infecções bacterianas.

Phenotypic and genotypic characterization of Streptococcus agalactiae in pregnant women: first study in a province of Argentina

Group B Streptococcus (GBS) is the leading cause of neonatal infections. Our purpose was to characterize GBS colonization in pregnant women, current serotypes, resistance phenotypes and genes associated with virulence. In Misiones, Argentina, there are no previous data on this topic. Vaginal-rectal swabs from 3125 pregnant women were studied between 2004 and 2010. GBS strains were identified by conventional and serological methods (Phadebact Strep B Test, ETC International, Bactus AB, Sweden). Serotypes were detected using Strep-B Latex (Statens Serum Institut, Denmark). Resistance phenotypes were determined by the double-disk test. Genes were studied by PCR. Maternal colonization was 9.38%. Resistance to erythromycin was 11.6%, and the constitutive phenotype was the predominant one. Serotype Ia was the most frequent, whereas serotypes IV, VI, VII and VIII were not detected. The lmb, bca and hylB genes were detected in more than 79% of the strains. In this study, the colonization rate with GBS and the serotype distribution were compared with studies reported in other areas of the country. The high resistance to erythromycin in Misiones justifies performing antibiotic susceptibility testing. The serotype distribution, the genes encoding putative virulence factors, and the patterns of resistance phenotypes of GBS may vary in different areas. They thus need to be evaluated in each place to devise strategies for prevention.

Optimización de metodologías de cribaje para la búsqueda de Streptococcus agalactiae en embarazadas / Optimization of screening methodologies for the detection of Streptococcus agalactiae in pregnant women

Streptococcus agalactiae es una causa importante de morbimortalidad en mujeres embarazadas y neonatos en todo el mundo. El objetivo del presente trabajo fue determinar la utilidad del medio cromogénico chromID Strepto B de bioMérieux para detectar S. agalactiae en embarazadas cuando la muestra es sembrada directamente en dicho medio o después del enriquecimiento en caldo de Todd Hewitt selectivo, opciones que se compararon con la metodología propuesta por el CDC . Se analizaron 1924 hisopados, 962 de introito vaginal y 962 rectales, correspondientes a 962 embarazadas entre la semana 35 y 37 de gestación, asistidas en distintos hospitales. Los hisopados se sembraron directamente en el medio chromID Strepto B (CR) y luego se colocaron en un caldo de Todd Hewitt selectivo, suplementado con 15 µg/ml de ácido nalidíxico y 10 µg/ml de colistina (CTH-sel). Luego de 24 h de incubación, se realizaron subcultivos en el medio CR y en agar con 5% de sangre de carnero (ASO). La prevalencia global de S. agalactiae fue de 17,4%. La sensibilidad, la especificidad y los valores predictivos positivo y negativo del subcultivo en CR del material desarrollado en el CTH -sel fueron 98,8%, 100%, 100% y 99,7% respectivamente, con una incubación de 48 h. Los valores correspondientes de la siembra directa fueron 57,8%, 100%, 100% y 90%. La sensibilidad del subcultivo en ASO del material desarrollado en el CTH -sel fue del 85%. Se destaca el excelente rendimiento del subcultivo en CR luego del enriquecimiento en caldo de Todd Hewitt selectivo en comparación con el método propuesto por el CDC.

Streptococcus agalactiae is a significant worldwide cause of morbidity and mortality in pregnant women and their newborn infants. The objective of this work was to determine the usefulness of bioMrieux chromogenic medium chromID Strepto B (CR) for detecting S. agalactiae in pregnant women from the selective Todd-Hewitt broth (sel-THB ) against the methods proposed by the CDC . A total of 1924 swabs were analyzed, 962 from vaginal introitus and 962 rectal, belonging to 962 women in weeks 35-37 of pregnancy. The swabs were directly seeded in CR. Both swabs were later placed in sel-THB with 15 µg/ml supplement of nalidixic acid and 10 µg/ml colistin. After 24 h of incubation, subcultures in CR medium and agar containing 5% sheep blood (SBA) were performed. The prevalence found was 17.4%. Sensitivity, specificity, positive and negative predictive values of sel-THB subcultures with CR supplement and 48 h incubation were: 98.8, 100, 100 and 99.7%, respectively. The corresponding values of direct harvest of the sample were 57.8, 100, 100, and 90%, respectively. Sensitivity of sel-THB in SBA was 85%. Sel-THB subculture performance in CR was outstanding in comparison with the method proposed by the CDC.

Papel de metaloproteases de Estreptococos do grupo B na interação, viabilidade celular e indução de apoptose e necrose em células endoteliais e epiteliais humanas / Role of metalloproteinases of Group B Streptococci in the interaction, cell viability and induction of apoptosis and necrosis in human epithelial and endothelial cells

Estreptococos do grupo B (EGB) é a principal causa de sepse e meningite neonatal e tem sido recentemente reconhecido como patógeno responsável por infecções invasivas em adultos imunocomprometidos (idosos ou portadores de doenças crônicas). Os EGB produzem inúmeras enzimas extracelulares, várias das quais interagem com o sistema imune do hospedeiro e são importantes durante a interação EGB-hospedeiro, bem como para o desenvolvimento da doença. Estudos anteriores mostraram que metaloproteases estão envolvidas em várias vias metabólicas em diferentes tipos celulares. Por esta razão, nós decidimos investigar o possível envolvimento de metaloproteases de EGB durante a interação celular e apoptose/necrose induzida pelo micro-organismo em células endoteliais da veia umbilical humana (HUVEC) e da linhagem de epitélio respiratório (A549). Tratamento de EGB com inibidores de metaloproteases (EDTA, EGTA e FEN) não induziu alterações no crescimento bacteriano, mas promoveu alterações na expressão de proteínas de superfície, capacidade adesiva e perfil de sobrevivência intracelular do patógeno. O EGB e o sobrenadante do crescimento bacteriano (meio condicionado; MC) promoveram a morte das células HUVEC e A549. Contudo, o tratamento com inibidores de metaloproteases restauraram a viabilidade celular induzida pelos EGB e o MC, sugerindo que metaloproteases bacteriana estão envolvidas no rompimento da barreira celular, promovendo a disseminação bacteriana. Este trabalho descreve pela primeira vez apoptose e necrose induzidas pelo EGB e MC em HUVEC e células A549 após 24h de incubação, respectivamente. Nós também observamos redução da pró-caspase-3 após infecção das HUVEC com EGB e MC, sugerindo ativação da caspase-3. Além disso, o aumento da expressão da proteína pró-apoptótica Bax e diminuição dos níveis da proteína anti-apoptótica Bcl-2 em HUVEC, demonstram o envolvimento do mecanismo apoptótico mitocondrial (via intrínseca). A melhor compreensão das bases molecular...

Group B streptococcus (GBS) is the leading cause of neonatal sepsis and meningitis and has recently been recognized as an increasingly common cause of invasive disease in immunocompromised adults (elderly or chronic diseases). GBS produces a number of extracellular enzymes, several of which interact with the host immune system and are important for the GBS- host interaction and for the development of disease. Previous studies showed that metalloproteases are involved in several metabolic pathways in different cellular types. For this reason, we decided to investigate the possible involvement of GBS metalloproteases during cell interaction and apoptosis/necrosis induced by microorganism in human umbilical vein endothelial cells (HUVEC) and epithelial respiratory cells line (A549). Treatment of GBS with metalloproteases inhibitors (EDTA, EGTA and PHEN) did not induce alteration on bacterial growth, but promoted changes in the expression of surface proteins, adhesive capacity and profile of intracellular survival of the pathogen. The GBS and supernatant of bacterial growth medium (conditioned medium; MC) promoted the death of HUVEC and A549 cells. However, the metalloproteases inhibitors treatment restored the cellular viability induced by GBS and MC, suggesting that GBS metalloproteases are involved in the disruption of cell barrier, promoting bacterial dissemination. This study describes for the first time apoptosis and necrosis induced by GBS and MC in HUVEC and A549 cells after 24h incubation, respectively. We also observe reduction of pro-caspase-3 after infection of HUVEC with GBS and MC, suggesting activation of caspase-3. Moreover, the over-expression of pro -apoptotic protein Bax and decrease of anti-apoptotic protein Bcl-2 levels in HUVEC show the involvement of mitochondrial apoptotic mechanism (intrinsic via). Enhanced understanding of the molecular basis of GBS pathogenesis may pinpoint novel bacterial and host molecules that can represent novel...

Particularites des infections invasives a streptocoque du groupe B de l'adulte

Une augmentation de l'incidence des infections invasives a streptocoque du groupe B (SGB) de l'adulte a ete notee dans plusieurs pays developpes. Tres peu de series decrivent la situation dans les pays en voie de developpement. Objectifs : Determiner les particularites epidemio-cliniques; les facteurs favorisants et les modalites evolutives de ce type d'infections observees dans un hopital tunisien.Methode : Analyse retrospective de 65 episodes suivis entre 1993 et 2007. Resultats : Le sex-ratio etait de 0;3 et la mediane des ages etait de 59 ans. Au moins un facteur favorisant etait note dans 73;8des patients. Ces facteurs etaient domines par le diabete et les infections urinaires recidivantes (25). Les urosepsis; les infections genitales et les bacteriemies sans foyer primitif evident dominaient les tableaux cliniques. Les infections etaient polymicrobiennes dans 13;9des cas. Tous les isolats de SGBetaient sensibles aux penicillines. L'evolution etait souvent favorable; 4;6des patients etaient decedes et 7;7avaient eu des recidives d'infections invasives au meme germe. Conclusion : Notre etude montre un spectre clinique particulier des infections invasives a SGB de l'adulte et confirme le role du terrain sous jacent dans ce type d'infection. Une etude tunisienne a plus large echelle permettra de preciser l'ampleur de ces infections dans notre pays

Pulsed-field gel electrophoresis, virulence determinants and antimicrobial susceptibility profiles of type Ia group B streptococci isolated from humans in Brazil

Group B streptococci (GBS) infections occur worldwide. Although serotyping has been used for epidemiologic purposes, this does not accurately characterize enough members of a genetically heterogeneous bacterial population. The aims of this work were to evaluate the genetic diversity of 45 type Ia GBS strains isolated in Brazil by pulsed-field gel electrophoresis as well as to evaluate antimicrobial susceptibility profiles and identify virulence genes. Twenty-four strains were assigned to cluster A. All strains under study contained the hylB and scpB genes. The bca gene was detected in only 10 strains and none of the streptococci carried the bac gene. Thirty-nine strains were resistant to tetracycline.

Síndrome de celulitis-adenitis inguinal por Streptococcus agalactiae / Cellulitis-adenitis syndrome inguinal Streptococcus agalactiae

Las infecciones de tejidos blandos en la infancia son producidas habitualmente por el Staphylococcus aureus pero, en los primeros meses de vida, el Streptococcus agalactiae (SGB) puede ser responsable de celulitis con afectación sistémica. El síndrome de celulitis-adenitis por SGB constituye una presentación infrecuente de la infección tardía causada por este germen. Las manifestaciones clínicas consisten en fiebre, mal estado general y signos inflamatorios locales. La localización más frecuente es la submaxilar, siendo excepcional la inguinal. Aportamos el caso de un paciente de 30 días de vida con fiebre, con una placa eritematosa y adenopatías en la zona inguinal derecha. En el hemocultivo se aisló SGB. El tratamiento inicial fue cloxacilina y cefotaxima parenterales cambiándose a las 48 horas, tras la recepción del hemocultivo, por cefotaxima y ampicilina. La evolución fue favorable. En niños menores de 3 meses, ante la presencia de celulitis y adenitis regional, debemos considerar al SGB como posible agente etiológico y contemplar la posibilidad de bacteriemia y afectación del sistema nervioso central para no diferir el tratamiento adecuado.

Soft-tissue infections in children are most often caused by Staphylococcus aureus but, in the first months of life, group B streptococcus (GBS) can be the etiologic agent of cellulitis with systemic involvement. Group B streptococcus cellulitis-adenitis syndrome is a rare form of late-onset disease for this germen. Clinical manifestations include fever and local inflammatory signs. Typical localization is submandibular but the inguinal form is exceptional. We present a case of a 30-day-old infant with fever, an erythematous plaque and lymphadenopathy in the right inguinal area. Blood culture was positive for GBS. Evolution was good with initial parenteral therapy with oxacylin and cefotaxime that was changed at 48 hours of treatment, after the blood culture reception, to ampicilin and cefotaxime. In cases of cellulitis and adenitis in infants during the first 3 months of life, GBS has to be considered the probable etiologic agent, and severe invasive disease has to be ruled-out in order to establish the appropriate antimicrobial therapy.

Infecciones por Streptococcus agalactiae en un servicio de neonatología abierto / Infections due to Streptococcus agalactiae at an open neonatology service

El objetivo del presente estudio fue conocer las características clínicas y epidemiológicas de las infecciones por estreptococo del grupo B en recién nacidos egresados de los hospitales maternos. Se realizó un estudio descriptivo, que incluyó a recién nacidos consecutivos con infecciones por Streptococcus agalactiae, ingresados en el Servicio de Neonatología del Hospital Pediátrico Universitario Juan M Márquez entre febrero de 1992 y diciembre del 2007. Se procesaron y analizaron distintas variables clínicas y epidemiológicas, con cálculo de tasas de incidencia y letalidad, así como relación entre variables categóricas. Hubo 76 recién nacidos con infección por Streptococcus agalactiae, lo cual constituyó una tasa promedio anual de 1,9 x 100 ingresos. Predominaron las infecciones de inicio tardío y las adquiridas en la comunidad (89,5 por ciento y 93,4 por ciento, respectivamente). La meningitis fue la forma clínica más frecuente, seguida de la bacteriemia aislada. Hubo 56 de 76 recién nacidos con bacteriemia (73,7 por ciento). El Streptococcus agalactiae tuvo elevada sensibilidad ante la penicilina, la eritromicina, la vancomicina, la cefotaxima y el cloranfenicol. Hubo 7 fallecidos (9,2 por ciento) y todos fueron pacientes con infección del sistema nervioso central. Streptococcus agalactiae es un agente causal de infecciones que afectan al recién nacido, tanto en la comunidad como en el medio hospitalario. Estas infecciones pueden ser letales en algunos pacientes con infección del sistema nervioso central con bacteriemia o sin ella, aún manteniendo un patrón de elevada susceptibilidad a los antibióticos betalactámicos.

The objective of the present study was to know the clinical and epidemiological characteristics of the infections caused by group B Streptococcus in newborns discharged from maternal hospitals. A descriptive study that included consecutive infants with infections due to Streptococcus agalactiae admitted in the Neonatology Service of ½Juan M. Mßrquez¼ University Pediatric Hospital from February 1992 to December 2007 was conducted. Different clinical and epidemiological variables were processed and analyzed, with calculation of incidence and lethality rates and relation among the categoric variables. There were 76 newborns with infection due to Streptococcus agalactiae for an average annual rate of 1,9 x 100 admissions. It was observed a predominance of late onset infections and of those acquired in the community (89,5 percent y 93,4 percent, respectively). Meningitis was the most common clinical form followed by isolated bacteriemia. 56 of the 76 newborn infants had bacteriemia (73,7 percent). Streptococcus agalactiae showed a high sensitivity to penicillin, erythromycine, vancomycin, cefotaxime and cloranphenicol. There were 7 deaths (9,2 percent). All of them had infection of the CNS. Streptococcus agalactiae is an agent that causes infections affecting the newborn infant, both in the community and in the hospital. These infections may be lethal in some patients with infection of the CNS with o without bacteriemia, even when they maintain a pattern of elevated susceptibility to betalactamic antibiotics.

Sepsis neonatal por Streptococcus Grupo B / Group B Streptococcus neonatal sepsis: up-to-date

Group B Streptococcus is one of the leading bacterias causing early onset neonatal sepsis. It constitutes an important factor of neonatal morbidity and mortality and high costs in health. Many strategies have been formulated to avoid vertical transmission from the colonized mother to the newborn, in an attempt to prevent infection of the infant. The most used nowadays is antibiotic prophylaxis given to the mother during labor, depending on the results of recto-vaginal culture taken during 35 to 37 weeks of gestation. This strategy has importantly diminished the prevalence of early onset neonatal sepsis by this agent, although there is still concern about the potential generation of antibiotic resistance and drug-induced adverse reactions in the mother. New techniques for prevention are being developed, such as vaccines against Streptococcus. In the newborn, infection caused by Streptococcus has a broad spectrum of clinical manifestations, like sepsis and meningitis which are the most frequent and lethal. Neurological sequelae are common among the survivors, so an early suspicion of disease must lead to a prompt antibiotic treatment.

El Streptococcus grupo B (SGB) es uno de los principales agentes causales de sepsis neonatal precoz, siendo un importante factor de morbimortalidad neonatal y de costos en salud pública. Se han implementado múltiples estrategias para evitar la transmisión vertical desde la madre colonizada a su recién nacido, de modo de prevenir la infección de éste último. La más usada en la actualidad es la profilaxis antibiótica administrada a la madre en el momento del parto dependiendo del resultado de un cultivo perineal realizado entre las semanas 35 y 37 de gestación. Mediante esta estrategia se ha logrado disminuir de manera importante la incidencia de la sepsis neonatal por este agente, pero existen aprehensiones acerca de la posible generación de resistencia antibiótica o reacciones adversas a fármacos por parte de la madre. Por esto último, nuevas técnicas de prevención se encuentran en estudio, como las vacunas contra el SGB. En los recién nacidos la infección por Streptococcus agalactiae puede manifestarse de diversas maneras, siendo la sepsis y la meningitis las más frecuentes y mortales. El porcentaje de secuelas entre los sobrevivientes es elevado, por lo que ante la sospecha precoz de infección debe iniciarse tratamiento antibiótico a la brevedad.

Profilaxis de sepsis neonatal por Streptococcus Agalactiae (grupo B) basada en vacunas: revisión de la literatura / Prophylaxis of early neonatal sepsis Streptococcus Agalactiae (group B) based on vaccines: literature review

El Streptococcus agalactiae o grupo B (SGB), es el principal agente de sepsis neonatal precoz. A pesar de los intentos de prevención de esta infección, aún no se logra la efectividad esperada. Es por esto que se ha intentado desarrollar una vacuna que pueda prevenir la mayoría de las patologías que esta bacteria produce, incluyendo la sepsis neonatal precoz y tardía. De esta manera se evitarían las limitaciones actuales de la profilaxis antibiótica. Los intentos de crear una vacuna han incluido la utilización de polisacáridos del SGB tanto puros como asociados a proteínas como el toxoide tetánico. También, se han usado proteínas específicas de la cápsula que tienen potencial efectividad como factores inmunogénicos. Las vacunas conjugadas son las más estudiadas en la actualidad, habiendo completado estudios clínicos en fase II, tanto en adultos sanos como en embarazadas. Al ser la sepsis neonatal una complicación grave aún no controlada óptimamente, la creación de una vacuna contra este patógeno sería de gran impacto en salud pública. Se presentan los diferentes tipos de vacunas desarrolladas y el estado de avance en el que se encuentran.

Streptococcus agalactiae or group B, is the mayor causing agent of early onset neonatal sepsis. Although mayor prevention strategies have been made, the expected effectiveness hasn't been achieved. That's why efforts have been made to develop a vaccine that can prevent most of the diseases these bacteria can produce, including early and late onset neonatal sepsis. These way, actual antibiotic prophylaxis limitations can be avoided. Attempts include the utilization of Streptococcus group B polysaccharides in their pure state or combined with proteins as tetanic toxoid. Specific capsule proteins have been used also because of their potential effectiveness as inmunogenic factors. Overall vaccines conjugated ones are the most studied, having completed phase II clinical trials in healthy adults and pregnant women. Neonatal sepsis is a severe complication that has not been controlled yet, so the creation of a vaccine against this pathogen would be of great impact in public health. We introduce now the different developed vaccines and their state of progress.

Infecções respiratórias altas: dor de garganta / Upper respiratory infections

As doenças das vias aéreas superiores fazem parte da rotina diária dos ambulatórios de Clínica Médica. O presente artigo destaca as doenças da orofaringe, em especial o sintoma de dor de garganta. Enfatiza os principais agentes etiológicos, por exemplo, vírus, bactérias ou fungos. Descreve o diagnóstico clínico, os exames complementares e a terapêutica específica para cada caso.

Colonización de Streptococcus beta hemolítico del grupo B en gestantes en trabajo de parto y sus neonatos / Colonization of hemolítico Streptococcus beta of group B in gestantes in work of childbirth and its neoborn ones

El objetivo de esta investigación fue establecer en pacientes atendidos en la Maternidad “Dr. Armando Castillo Plaza”, Maracaibo, Venezuela, la relación de la colonización del Streptococcus beta hemolítico del grupo B (SGB) en la vagina y recto de las gestantes a término en trabajo de parto y la colonización de sus neonatos, entre los meses Mayo a Diciembre del 2004. Se estudiaron 100 gestantes con embarazos simples a término en trabajo de parto, independientemente de su edad cronológica y paridad, excluyéndose aquellas embarazadas con ruptura prematura de membrana mayor de 18 horas, con antibioticoterapia en el momento del parto, con fiebre intraparto, coriamnionitis o con antecedente de parto anterior con infección del recién nacido por el SGB. A cada paciente se le tomó hisopado vaginal rectal y secreción nasal a sus neonatos al momento del parto, los cuales se colocaron en un medio de Cary & Blair y se transportaron al laboratorio de bacteriología donde las muestras de vagina y de secreción nasal se cultivaron en agar sangre de carnero con Kanamicina; las muestras rectales se inocularon en agar sangre de carnero con Kanamicina y en caldo cerebro corazón con Ácido Nalidixico y Gentamicina. El SGB fue identificado mediante pruebas convencionales y una vez identificadas se les realizó las pruebas de susceptibilidad siguiendo la metodología descrita por el CLSI 2007 (Bauer & Kirby). La frecuencia de aislamiento del SGB fue de 18% en las pacientes estudiadas y del 10% en sus recién nacidos. La transmisión vertical en el momento del parto fue 55,5%. Los aislamientos de SGB fueron sensibles a todos los antibióticos probados. La frecuencia de colonización en las parturientas y en los neonatos es comparable con las reportadas en otros países. Es necesario establecer pautas para detectar la colonización materna por SGB y así prevenir la sepsis neonatal por este microorganismo.

The objective of this investigation was to establish in patients taken care of in the Maternity “ Dr. Armando Castillo Plaza”, Maracaibo, Venezuela, the relation of the colonization of the hemolítico Streptococcus beta of the B group (SGB) in the vagina and rectum of the gestantes upon maturity in work of childbirth and the colonization of its neoborn ones, between the months May to December of the 2004. 100 gestantes with simple pregnancies in work of childbirth studied upon maturity, independently of its chronological age and parity, excluding themselves those pregnant women with greater membrane premature rupture of 18 hours, with antibioticoterapia at the moment of the childbirth, with fever intrachildbirth, coriamniotitis or with antecedent of previous childbirth with infection of new born by the SGB. To each patient hisopado was taken her vaginal rectal and nasal secretion to its neoborn ones at the time of the childbirth, which was placed in means of Cary & Blair and they were transported to the bacteriology laboratory where the nasal secretion and vagina samples were cultivated in agar blood of sheep with kanamicina; the rectal samples inoculated in agar blood of sheep with kanamicina and in broth brain heart with nalidixico acid and gentamicina. The SGB was identified by means of conventional tests and once identified the methodology described by CLSI 2007 was made the susceptibility tests to them following (Bauer & Kirby). The frequency of isolation of the SGB was of 18% in the studied patients and 10% in new born her. Vertical transmission in the moment of the childbirth was 55.5%. The isolations of SGB were sensible to all proven antibiotics. The frequency of colonization in parturientas and the neoborn ones is comparable with the reported ones in other countries. It is necessary to establish guidelines to detect the maternal colonization by SGB and thus to prevent the neonative sepsis by this microorganism.

Aproximación a la situación epidemiológica en Argentina de la infección perinatal por estreptococo beta hemolítico del grupo B (EGB) / Approach to the epidemiologic situation in Argentina of the perinatal infection by beta hemolytic streptococcus of the B group (EGB)

Objetivo: Evaluar la validez de las Recomendaciones para la prevención, diagnóstico y tratamiento de la infección neonatal precoz por Estreptococo beta hemolítico del grupo B (EGB) (Ministerio de Salud Argentina 2004) que priorizan los factores de riesgo como método de prevención. Material y método: entre abril-junio 2005 se obtuvo información de 43 servicios de 5 provincias. Las variables fueron: Metodología de prevención utilizada, n partos, n cultivos realizados a embarazadas, porcentaje sobre el total de partos, n cultivos positivos, porcentaje sobre el total de los realizados, n tratadas, porcentaje sobre total de cultivadas, n RN afectados y por mil nacidos vivos y su mortalidad. No hubo información sobre metodología de cultivo. Resultados: En 25 servicios se realiza cultivo; en 17 se realizaron 10.317 cultivos, fueron positivos 861: el 8,34 por ciento de embarazadas colonizadas con EGB (rango O a 18,5 por ciento). Las embarazadas cultivadas fueron 38,6 por ciento (rango 12,2 a 75,27 por ciento). Tratadas intraparto entre el 47 al 100 por ciento de las positivas. En 7 de esos servicios los RN afectados fueron 0,27 cada mil nacimientos (rango O a 0,88 por mil), la mortalidad fue del 20 por ciento. En 12 Servicios se emplean factores de riesgo, en 3 de ellos con datos completos hubo 57.862 nacimientos y 0,31 recién nacidos afectados por mil nacidos vivos. La mortalidad fue del 27 por ciento. No hubo diferencias estadísticamente significativas entre los resultados de ambos grupos de servicios (p=0.78 sepsis neonatal y p=0,66 mortalidad). Seis servicios informaron no utilizar ninguna medida de prevención. Conclusión: La colonización de las embarazadas es baja y el cultivo es difícil de implementar en forma universal. La utilización de factores de riesgo (en un servicio) disminuyó la incidencia de afectación neonatal. No hubo diferencias sustantivas en los resultados neonatales entre los servicios que realizaron cultivos y aquellos que utilizaron factores de riesgo, tal vez debido a la baja incidencia de colonización materna. En resumen, los resultados no sustentan el cambio de la recomendación realizada el año 2004.

[Streptococcus agalactiae in nonpregnant adult]

The pathogenic capacity of streptococcus agalactiae or Group B Streptococcus [GBS] has been increasing in nonpregnant adults. We carried out a study about the pathogenic capacity and susceptibility to antibiotics of GBS strains isolated between January 2003 and June 2004 in Farhat Hached hospital of Sousse [Tunisian general hospital]. Identification of strains was carried out according to usual bacteriological characters. Susceptibility of GBS to antibiotics was carried out according to CA-SFM recommendations. During the study period, sixty strains were isolated. They were essentially isolated from the urinary tract [52%] and the skin [36.2%]. Women accounted for 68 percent of the cases. Among the 30 hospitalized patients, 20 [66%] had serious underlying disease. Diabetes mellitus was predominant [80%]. All group B streptococci isolates were susceptible to amoxicillin, penicillin G. vancomycin and to pristinamycin. Sixty four percent of isolates were susceptible to erythromycin. Among the invasive infection, caused by GBS in nonpregnant adults, skin and urinary tract infections were the most common. All isolates were susceptible to amoxicillin, penicillin G, vancomycin and to pristinamycin

Streptococcus agalactiae em gestantes: prevalência de colonização e avaliação da suscetibilidade aos antimicrobianos / Streptococcus agalactiae in pregnant women: prevalence of colonization and antimicrobial susceptibility evaluation

OBJETIVOS: verificar a ocorrência de colonização por Streptococcus agalactiae em gestantes e avaliar a suscetibilidade das amostras isoladas aos antimicrobianos. MÉTODOS: foram avaliadas 167 grávidas entre a 32ª e a 41ª semana de gestação, independente da presença ou não de fatores de risco, atendidas no ambulatório de pré-natal entre fevereiro de 2003 e fevereiro de 2004. O material vaginal/anal, colhido com um único swab, foi inoculado em caldo Todd-Hewitt acrescido de ácido nalidíxico (15 æg/mL) e gentamicina (8 æg/mL), com posterior subcultura no meio de ágar sangue. A identificação foi feita por meio da avaliação da morfologia e tipo de hemólise das colônias no meio de ágar sangue, teste da catalase, teste de cAMP e testes sorológicos. A avaliação da suscetibilidade aos antimicrobianos foi realizada pelos testes de difusão e de diluição em ágar. A análise estatística foi realizada por meio do teste de chi2; valores de p<0,05 foram considerados significativos. RESULTADOS: a freqüência de colonização foi de 19,2 por cento, sem diferenças significativas com relação à idade, número de gestações, ocorrência de abortos e presença ou ausência de diabete melito (p>0,05). Todas as 32 amostras isoladas foram sensíveis a penicilina, cefotaxima, ofloxacina, cloranfenicol, vancomicina e meropenem. A resistência a eritromicina e clindamicina foi detectada em 9,4 e 6,2 por cento das amostras, respectivamente. CONCLUSÕES: a incidência relativamente elevada (19,2 por cento) de colonização por S. agalactiae entre as gestantes avaliadas e o isolamento de amostras resistentes, especialmente aos antimicrobianos recomendados nos casos de alergia à penicilina, enfatizam a importância de detectar esta colonização no final da gravidez, associada à avaliação da suscetibilidade aos antimicrobianos, para uma prevenção eficaz da infecção neonatal.