Streptococcus equi subsp. zooepidemicus: High molecular diversity of Argentinian strains isolated from mares with endometritis.

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is a mucosal commensal of the lower genital tract in horses and is the most isolated bacterium causing endometritis in mares. The aim of this study was to determine the molecular diversity of S. zooepidemicus obtained from endometritis in mares in Buenos Aires province, Argentina. Thirty isolates obtained from the uterus of mares in 2005 and 2017 were studied. The MLST scheme was applied to identify the Argentinian genotypes and the clonal relationships and patterns of evolutionary descent were identified using the eBURST algorithm - goeBURST. Twenty six different Sequence types (STs) were identified, being only 11 of them previously reported in horses and also, from several host species and tissues. The other 15 STs were reported in Argentinian reproductive strains of mares in our study for the first time. The genotypes obtained from uterus in Argentina were not evenly distributed when all the published S. zooepidemicus STs were analysed, thus, it was not possible to establish that the same lineage circulates in our equine population. The fact that the identified genotypes were also reported in other countries, diverse samples and host species suggest that there is not a host, and an anatomical niche adaptation. Finally, the isolation of the same genotype in the vagina/clitoris and the uterus of the same mare highlights the versatility of S. zooepidemicus and its role as an opportunistic pathogen.

Low lineage diversity and increased virulence of group C Streptococcus dysgalactiae subsp. equisimilis.

Introduction. In some species, the population structure of pathogenic bacteria is clonal. However, the mechanisms that determine the predominance and persistence of specific bacterial lineages of group C Streptococcus remain poorly understood. In Brazil, a previous study revealed the predominance of two main lineages of Streptococcus dysgalactiae subsp. equisimilis (SDSE).Aim. The aim of this study was to assess the virulence and fitness advantages that might explain the predominance of these SDSE lineages for a long period of time.Methodology. emm typing was determined by DNA sequencing. Adhesion and invasion tests were performed using human bronchial epithelial cells (16HBE14o-). Biofilm formation was tested on glass surfaces and the presence of virulence genes was assessed by PCR. Additionally, virulence was studied using Caenorhabditis elegans models and competitive fitness was analysed in murine models.Results. The predominant lineages A and B were mostly typed as emm stC839 and stC6979, respectively. Notably, these lineages exhibited a superior ability to adhere and invade airway cells. Furthermore, the dominant lineages were more prone to induce aversive olfactory learning and more likely to kill C. elegans. In the competitive fitness assays, they also showed increased adaptability. Consistent with the increased virulence observed in the ex vivo and in vivo models, the predominant lineages A and B showed a higher number of virulence-associated genes and a superior ability to accumulate biofilm.Conclusion. These results suggest strongly that this predominance did not occur randomly but rather was due to adaptive mechanisms that culminated in increased colonization and other bacterial properties that might confer increased bacteria-host adaptability to cause disease.

Genotyping and antimicrobial resistance of Streptococcus uberis isolated from bovine clinical mastitis.

A genotypic characterization of Streptococcus uberis isolated from clinical mastitis (CM) in dairy cows, and the association of Strep. uberis genotypes and antimicrobial susceptibility (AMS) was performed. A total of 89 isolates identified as Strep. uberis from 86 dairy cows with CM in 17 dairy herds of Southeastern Brazil were genotyped using random amplified polymorphic DNA (RAPD) analysis. After genotyping, two clusters (I and II) were created according to RAPD types. A commercial broth microdilution test was used to determine the susceptibility of Strep. uberis isolates to 8 antimicrobials (ampicillin, ceftiofur, cephalothin, erythromycin, penicillin, penicillin+novobiocin, pirlimycin and tetracycline). For each antimicrobial, we determined the minimal inhibitory concentrations that inhibit 50% (MIC50) and 90% (MIC90) of Strep. uberis strains. Differences in AMS among genotypic clusters were evaluated using mixed regression models. Overall, a great polymorphism (56 RAPD-types) was found among Strep. uberis isolates, although a higher genetic similarity (based on the PCR bands features) was observed within herds after genotypic clustering. No differences in AMS were observed among clusters. Strep. uberis isolated from bovine CM were resistant to most antimicrobials, with the exception of cephalothin and penicillin+novobiocin.

Prevalence and long-term persistence of beta-haemolytic streptococci throat carriage among children and young adults.

Introduction. Among beta-haemolytic streptococci, Streptococcus pyogenes (GAS) is the prototype agent of bacterial pharyngitis and causes other human infections. Streptococcus dysgalactiae subsp. equisimilis (SDSE) causes GAS-like infections, while Streptococcus agalactiae (GBS) is a common neonate pathogen that is rarely associated with pharyngitis.Aim. To determine the prevalence and persistence of beta-haemolytic streptococci throat carriage and type the bacterial population.Methods. Throat swabs were collected from 121 children and 127 young adult volunteers and cultured. Colonized volunteers were screened quarterly, for up to 1 year, while beta-haemolytic streptococci could be detected. Isolates were identified and submitted to antimicrobial susceptibility testing and epidemiological typing.Results. Carriage was detected in 34 (13.7 %) volunteers. Seventeen children carried GAS (14 %), while 17 young adults carried SDSE (8, 6.3 %), GBS (4, 3.1 %), GAS (3, 2.4 %) and the Streptococcus anginosus group (2, 1.6 %). Persistent carriage was detected for up to 6 months in two children and for up to 1 year in three young adults. Three new emm subtypes were found, emm87.16 and emm90.9 (GAS) and stC36.11 (SDSE). While the GAS population among children was unexpectedly clonal, substantial genetic diversity was found among the isolates recovered from young adults. Resistance to erythromycin, clindamycin and tetracycline was detected in GAS, GBS and SDSE recovered from young adults.Conclusions. Prevalence was slightly greater among children, but persistent carriage was greater among young adults, with SDSE being the species most associated with persistence. Few sources seemed to disseminate GAS among children, since only two clonal types were found. The volunteers hosted pathogenic streptococci persistently, including macrolide-resistant strains.

Genotyping and study of adherence-related genes of Streptococcus uberis isolates from bovine mastitis.

The aim of this study was to determine the presence, conservation, and distribution of 6 potential adherence genes and their relationship with diverse molecular types in 34 S. uberis isolated from bovine mastitis in Argentina. Pulsed-field gel electrophoresis (PFGE) typing with SmaI was performed. The PCR for the detection of each gene, scpA, acdA, fbp, lbp, lmb, and sua was standardized. Samples of the amplification products were purified and sequenced. The PFGE patterns revealed the high level of heterogeneity of S. uberis, with 26 types of PFGE patterns. A high prevalence of scpA, fbp, lbp, lmb and acdA genes (100%-97%) was detected, whereas 79.41% of S. uberis harbored the sua gene. A high degree of similarity in the nucleotide and amino acid sequences of the 6 genes was observed. Our results showed that all genes are conserved and are present in most S. uberis isolates despite the wide clonal heterogeneity detected. This is the first study reporting an analysis of prevalence, and nucleotides and amino acids sequences of the potential adherence genes scpA, acdA, fbp, lbp, and lmb from S. uberis strains versus reported GenBank sequences, S. uberis 0140J and S. uberis NZ01.

Streptococcus penaeicida sp. nov., isolated from a diseased farmed Pacific white shrimp (Penaeus vannamei).

Strain CAIM 1838T, isolated from the hepatopancreas of a cultured diseased Pacific white shrimp (Penaeus vannamei), was subjected to characterization by a polyphasic taxonomic approach. On the basis of 16S rRNA gene sequence analysis, strain CAIM 1838T was most closely related to Streptococcus bovimastitidis 99.3 % and to other species of the Pyogenes clade of Streptococcus with lower similarity values. Average nucleotide identity values and the genome-to-genome distance of strain CAIM 1838T, as compared with the type strains, confirmed the separate species status with closely related species of the genus Streptococcus and were all below the thresholds to delimit a species, 93.1 and 49.4 %, respectively. The DNA G+C content was 38.1 mol%. Differential phylogenetic distinctiveness together with phenotypic properties obtained in this study revealed that strain CAIM 1838T could be differentiated from the closely related species. Based on these results it is proposed that strain CAIM 1838T represents a novel species in the genus Streptococcus, for which the name Streptococcus penaeicida sp. nov is proposed (type strain, CAIM 1838T=CECT 8596T,=DSM26545T), is proposed.

Clorina com fotossensibilizador para Terapia Fotodinâmica sobre Streptococcus mutans / Clhorine as photosensibilizer for photodynamic therapy on Streptococcus mutans

A terapia fotodinâmica (TFD) vem se mostrando eficaz na redução de patógenos bucais e diferentes fotossensibilizadores têm sido investigados. O objetivo desse estudo foi avaliar a eficácia da TFD sobre Streptococcus mutans usando dois fotossensibilizadores derivados da Clorina, Photoditazine (PDZ) e Fotoenticine (FTC), associados à irradiação Laser (660nm, 50 mw/cm²). Esses fotossensibilizadores também foram comparados com o Azul de Metileno (AM) que já tem seus efeitos comprovados contra S. mutans. Para realização desse trabalho, foram isoladas 11 amostras clínicas de S. mutans a partir de pacientes com lesões de cáries ativas. Essas amostras foram identificadas pela Reação em Cadeia da Polimerase (PCR), seguida por confirmação em sequenciamento automático. Também foi incluída no estudo uma cepa padrão de referência (S. mutans UA159). Os efeitos da TFD foram testados sobre S. mutans em culturas planctônicas e sobre biofilmes formados em dentes bovinos. Os resultados foram avaliados pela contagem de células viáveis e Microscopia Eletrônica de Varredura (MEV). A capacidade dos fotossensibilizadores em penetrar nas células de S. mutans foi avaliada por meio da absorbância em espectrofotômetro. Os dados foram analisados por ANOVA e teste de Tukey. Na identificação das amostras, verificou-se que todas apresentaram o fragmento de 517 pb específico para S. mutans e que o sequenciamento demonstrou similaridade de 87% com a cepa de referência. Em culturas planctônicas, todos os fotossensibilizadores reduziram as células de S. mutans com diferença significante em relação ao grupo sem tratamento. O FTC conseguiu atingir 100% de redução tanto para a cepa de referência como para as cepas clínicas. Nos testes em biofilmes, houve redução bacteriana de 4 log para o AM, 6 log para o PDZ e de 5 a 8 log para o FTC. Na cepa padrão de referência, o FTC levou a eliminação total das células de S. mutans. Além disso, verificou-se que o FTC foi o fotossensibilizador com maior capacidade de desestruturar o biofilme e penetrar nas células de S. mutans. Concluiu-se que os fotossensibilizadores derivados da clorina demonstraram maior atividade antimicrobiana na TFD contra S. mutans em relação ao AM, sendo esse efeito mais significativo para o FTC(AU)

Photodynamic therapy (PDT) has been shown to be effective in reducing oral pathogens and different photosensitizers have been investigated. The objective of this study was to evaluate the efficacy of PDT on Streptococcus mutans using two photosensitizers derived from Chlorine, Photoditazine (PDZ) and Fotoenticine (FTC) associated with Laser irradiation (660 nm, 50 mw / cm²). These photosensitizers were also compared to Methylene Blue (AM) that already has its proven effects against S. mutans. To perform this work, 11 clinical samples of S. mutans were isolated from patients with active caries lesions. These samples were identified by the Polymerase Chain Reaction (PCR), for confirmation in automatic sequencing. Also included in the study was a standard standard (S. mutans UA159). The effects of PDT were tested on S. mutans in planktonic cultures and on biofilms formed in bovine teeth. Results of viable cell and Scanning Electron Microscopy (SEM) tests. The ability of the photosensitizers to penetrate the S. mutans cells was evaluated by spectrophotometer absorption. Data were analyzed by ANOVA and Tukey's test. In the identification of the samples, all the presentations of the 517 bp fragment specific for S. mutans and that the sequencing demonstrate similarity of 87% with a reference strain were found. In planktonic cultures, all photosensitizers reduced as S. mutans cells with a significant difference in relation to the untreated group. The FTC achieved a 100% reduction for both the reference strain and the clinical strains. In biofilm tests, there was a 4 log reduction for AM, 6 log for PDZ and 5 to 8 log for FTC. In the standard reference strain, FTC led to the complete elimination of S. mutans cells. In addition, it was found that FTC was the photosensitizer with the greatest capacity to de-structure the biofilm and penetrate S. mutans cells. It was concluded that the photosensitizers derived from chlorine showed a greater antimicrobial activity in PDT against S. mutans in relation to AM, being this effect more significant for the FTC(AU)

Evaluation of protein spectra cluster analysis for Streptococcus spp. identification from various swine clinical samples.

Traditional microbiological methods enable genus-level identification of Streptococcus spp. isolates. However, as the species of this genus show broad phenotypic variation, species-level identification or even differentiation within the genus is difficult. Herein we report the evaluation of protein spectra cluster analysis for the identification of Streptococcus species associated with disease in swine by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A total of 250 S. suis-like isolates obtained from pigs with clinical signs of encephalitis, arthritis, pneumonia, metritis, and urinary or septicemic infection were studied. The isolates came from pigs in different Brazilian states from 2001 to 2014. The MALDI-TOF MS analysis identified 86% (215 of 250) as S. suis and 14% (35 of 250) as S. alactolyticus, S. dysgalactiae, S. gallinaceus, S. gallolyticus, S. gordonii, S. henryi, S. hyointestinalis, S. hyovaginalis, S. mitis, S. oralis, S. pluranimalium, and S. sanguinis. The MALDI-TOF MS identification was confirmed in 99.2% of the isolates by 16S rDNA sequencing, with MALDI-TOF MS misidentifying 2 S. pluranimalium as S. hyovaginalis. Isolates were also tested by a biochemical automated system that correctly identified all isolates of 8 of the 10 species in the database. Neither the isolates of the 3 species not in the database ( S. gallinaceus, S. henryi, and S. hyovaginalis) nor the isolates of 2 species that were in the database ( S. oralis and S. pluranimalium) could be identified. The topology of the protein spectra cluster analysis appears to sustain the species phylogenetic similarities, further supporting identification by MALDI-TOF MS examination as a rapid and accurate alternative to 16S rDNA sequencing.

Molecular and antimicrobial susceptibility profiling of atypical Streptococcus species from porcine clinical specimens.

The Streptococcus species present broad phenotypic variation, making identification difficult using only traditional microbiological methods. Even though Streptococcus suis is the most important species for the worldwide swine industry, other Streptococcus species appear to be able to cause disease in swine and could represent a higher underestimated risk for porcine health. The aim of this study was to identify Streptococcus-like isolates by MALDI-TOF MS and 16S rRNA sequencing and further molecular and antibiotic susceptibility characterization of the atypical Streptococcus species capable of causing disease in swine. Fifty presumptive Streptococcus isolates from diseased pigs isolated from different Brazilian States between 2002 and 2014 were evaluated. Among the studied isolates, 26% were identified as Streptococcus hyovaginalis, 24% as Streptococcus plurianimalium, 12% as Streptococcus alactolyticus, 10% as Streptococcus hyointestinalis, and the remaining isolates belonged to Streptococcus henryi (6%), Streptococcus thoraltensis (6%), Streptococcus gallolyticus (6%), Streptococcus gallinaceus (4%), Streptococcus sanguinis (4%), and Streptococcus mitis (2%). The Streptococcus isolates were successfully identified by spectral cluster analysis and 16S rRNA sequencing with 96% of concordance between the techniques. The SE-AFLP analysis also supported Streptococcus species distinction and enabled further observation of higher genetic heterogeneity intra-species. The identified Streptococcus species presented variable MIC values to ß-lactams, enrofloxacin and florfenicol, and high resistance rates to tetracyclines and macrolides, which appear to be directly related to the industry's antimicrobial usage and resistance selection.

Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis.

This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%), Pseudoramibacter (10.7%) and Streptococcus (5.5%). Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection.

The Relevance of a Novel Quantitative Assay to Detect up to 40 Major Streptococcus pneumoniae Serotypes Directly in Clinical Nasopharyngeal and Blood Specimens.

For epidemiological and surveillance purposes, it is relevant to monitor the distribution and dynamics of Streptococcus pneumoniae serotypes. Conventional serotyping methods do not provide rapid or quantitative information on serotype loads. Quantitative serotyping may enable prediction of the invasiveness of a specific serotype compared to other serotypes carried. Here, we describe a novel, rapid multiplex real-time PCR assay for identification and quantification of the 40 most prevalent pneumococcal serotypes and the assay impacts in pneumonia specimens from emerging and developing countries. Eleven multiplex PCR to detect 40 serotypes or serogroups were optimized. Quantification was enabled by reference to standard dilutions of known bacterial load. Performance of the assay was evaluated to specifically type and quantify S. pneumoniae in nasopharyngeal and blood samples from adult and pediatric patients hospitalized with pneumonia (n = 664) from five different countries. Serogroup 6 was widely represented in nasopharyngeal specimens from all five cohorts. The most frequent serotypes in the French, South African, and Brazilian cohorts were 1 and 7A/F, 3 and 19F, and 14, respectively. When both samples were available, the serotype in blood was always present as carriage with other serotypes in the nasopharynx. Moreover, the ability of a serotype to invade the bloodstream may be linked to its nasopharyngeal load. The mean nasopharyngeal concentration of the serotypes that moved to the blood was 3 log-fold higher than the ones only found in the nasopharynx. This novel, rapid, quantitative assay may potentially predict some of the S. pneumoniae serotypes invasiveness and assessment of pneumococcal serotype distribution.

A study on ß-defensin-2 and histatin-5 as a diagnostic marker of early childhood caries progression.

BACKGROUND: Recently, a continuous growth of interest has been observed in antimicrobial peptides (AMPs) in the light of an alarming increase in resistance of bacteria and fungi against antibiotics. AMPs are used as biomarkers in diagnosis and monitoring of oral cavity pathologies. Therefore, the determination of specific protein profiles in children diagnosed with early childhood caries (ECC) might be a basis for effective screening tests and specialized examinations which may enable progression of disease. METHODS: The objective of the studies was to determine the role of histatin-5 and ß-defensing-2 as a diagnostic marker of early childhood caries progression. In this work, results of concentration determination of two salivary proteins (histatin-5 and ß-defensin-2) were presented. In addition, bacterial profiles from dental plaque in various stages of ECC and control were marked. The assessment of alteration in the concentration of these two proteins in a study group of children with various stages of ECC and a control group consisting of children with no symptoms was performed by enzyme-linked immunosorbent assays. RESULTS: The statistical analysis showed a significant increase in the concentration of histatin-5 and ß-defensin-2 in the study group compared to the control group and correlated with the progression of the disease. CONCLUSIONS: The confirmation of concentration changes in these proteins during the progression of dental caries may discover valuable disease progression biomarkers.

[Early neonatal sepsis, incidence and associated risk factors in a public hospital in western Mexico]. / Sepsis neonatal temprana, incidencia y factores de riesgo asociados en un hospital público del occidente de México.

BACKGROUND: Early neonatal sepsis (EOS) is the second leading cause of death in the first week of life. Epidemiology differs in developed and developing countries. AIM: To describe the epidemiology of EOS among newborn patients in a public hospital in western Mexico. METHODS: A prospective cohort study was performed in newborns of Nuevo Hospital Civil de Guadalajara "Dr. Juan I Menchaca". EOS was diagnosed with blood cultures or cultures of cerebrospinal fluid within the first 72 h of life. We analyzed risk factors (RF) by multivariate analysis with logistic regression. RESULTS: We identified an EOS incidence of 4.7 events per 1,000 live births. Seventy two percent of the isolated bacteria were gram negative bacilli. Factors associated with EOS were maternal age≤15 years (OR 3.50; 95% CI 1.56-7.85), rupture of membranes>18 h (OR 2.65; 95% CI 1.18-5.92), maternal fever (OR 6.04; 95% CI 1.54-23.6), birth weight≤2,500 g (OR 4.82; 95% CI 2.38-9.75) and gestational age<37 weeks (OR 3.14; 95% CI 1.58-6.22). CONCLUSIONS: In addition to the RF known for EOS an independent association was observed with maternal age≤15 years.

Molecular phylogeny and a taxonomic proposal for the genus Streptococcus.

Alternative phylogenies for the genus Streptococcus have been proposed due to uncertainty about the among-species group relationships. Here, we performed a phylogenetic analysis of the genus Streptococcus, considering all the species groups and also the genomic data accumulated by other studies. Seventy-five species were subjected to a Bayesian phylogenetic analysis using sequences from eight genes (16S rRNA, rpoB, sodA, tuf, rnpB, gyrB, dnaJ, and recN). On the basis of our results, we propose a new Phylogeny for the genus, with special emphasis on the inter-species group level. This new phylogeny differs from those suggested previously. From topological and evolutionary distance criteria, we propose that gordonii, pluranimalium, and sobrinus should be considered as new species groups, in addition to the currently recognized groups of mutans, bovis, pyogenic, suis, mitis, and salivarius.

Oral Streptococci Biofilm Formation on Different Implant Surface Topographies.

The establishment of the subgingival microbiota is dependent on successive colonization of the implant surface by bacterial species. Different implant surface topographies could influence the bacterial adsorption and therefore jeopardize the implant survival. This study evaluated the biofilm formation capacity of five oral streptococci species on two titanium surface topographies. In vitro biofilm formation was induced on 30 titanium discs divided in two groups: sandblasted acid-etched (SAE- n = 15) and as-machined (M- n = 15) surface. The specimens were immersed in sterilized whole human unstimulated saliva and then in fresh bacterial culture with five oral streptococci species: Streptococcus sanguinis, Streptococcus salivarius, Streptococcus mutans, Streptococcus sobrinus, and Streptococcus cricetus. The specimens were fixed and stained and the adsorbed dye was measured. Surface characterization was performed by atomic force and scanning electron microscopy. Surface and microbiologic data were analyzed by Student's t-test and two-way ANOVA, respectively (P < 0.05). S. cricetus, S. mutans, and S. sobrinus exhibited higher biofilm formation and no differences were observed between surfaces analyzed within each species (P > 0.05). S. sanguinis exhibited similar behavior to form biofilm on both implant surface topographies, while S. salivarius showed the lowest ability to form biofilm. It was concluded that biofilm formation on titanium surfaces depends on surface topography and species involved.

[Granulicatella spp]. / Granulicatella spp.

Granulicatella spp. is a bacteria of the oral cavity, belonging to the nutritionally variant group streptococci, and has been identified in 5% of all bacterial endocarditis. It's an important etiologic species in endocarditis, particularly in the setting of negative blood cultures. Granulicatella is a non-mobile, non- spore forming organism that is both catalase and oxidase negative. The treatment for Granulicatella, is the same for Enterococcus according to the American and European guidelines, however resistance to this treatment has been reported.

Sepsis neonatal temprana, incidencia y factores de riesgo asociados en un hospital público del occidente de México / Early neonatal sepsis, incidence and associated risk factors in a public hospital in western Mexico

Background: Early neonatal sepsis (EOS) is the second leading cause of death in the first week of life. Epidemiology differs in developed and developing countries. Aim: To describe the epidemiology of EOS among newborn patients in a public hospital in western Mexico. Methods: A prospective cohort study was performed in newborns of Nuevo Hospital Civil de Guadalajara "Dr. Juan I Menchaca". EOS was diagnosed with blood cultures or cultures of cerebrospinal fluid within the first 72 h of life. We analyzed risk factors (RF) by multivariate analysis with logistic regression. Results: We identified an EOS incidence of 4.7 events per 1,000 live births. Seventy two percent of the isolated bacteria were gram negative bacilli. Factors associated with EOS were maternal age ≤ 15 years (OR 3.50; 95% CI 1.56-7.85), rupture of membranes > 18 h (OR 2.65; 95% CI 1.18-5.92), maternal fever (OR 6.04; 95% CI 1.54-23.6), birth weight ≤ 2,500 g (OR 4.82; 95% CI 2.38-9.75) and gestational age < 37 weeks (OR 3.14; 95% CI 1.58-6.22). Conclusions: In addition to the RF known for EOS an independent association was observed with maternal age ≤ 15 years.

Introducción: La sepsis neonatal temprana (SNT) es la segunda causa de muerte en la primer semana de vida; la epidemiología difiere en países desarrollados y en vías de desarrollo. Objetivo: Describir la epidemiología de SNT en recién nacidos (RN) de un hospital público del occidente de México. Material y Métodos: Estudio de cohorte prospectivo en RN del Nuevo Hospital Civil de Guadalajara "Dr. Juan I Menchaca". Se diagnosticó SNT con cultivos de sangre o líquido cefalorraquídeo en las primeras 72 h de vida. Se indagaron factores de riesgo (FR) mediante análisis multivariado con regresión logística. Resultados: La incidencia de SNT fue de 4,7 eventos por 1.000 RN vivos. El 72% de las bacterias aisladas correspondió a bacilos gramnegativos. Los factores asociados a SNT fueron la edad materna ≤ 15 años (OR 3,50; IC 95% 1,56-7,85), ruptura de membranas > 18 h (OR 2,65; IC 95% 1,18-5,92), fiebre materna (OR 6,04; IC 95%1,54-23,6), peso al nacimiento ≤ 2.500 g (OR 4,82; IC 95% 2,38-9,75) y edad gestacional < 37 semanas (OR 3,14; IC 95% 1,58-6,22). Conclusiones: Además de los FR ya conocidos para SNT se observó asociación independiente con edad materna ≤ 15 años.

Evaluation of cytokines produced by β-hemolytic streptococcus in acute pharyngotonsillitis / Avaliação das citosinas produzidas por estreptococos β-hemolíticos em faringotonsilites agudas

INTRODUCTION: The most common pathogen in bacterial pharyngotonsillitis is group A β-hemolytic streptococcus, although groups B, C, F,and G have also been associated with pharyngotonsillitis.OBJECTIVE: To assess the levels of the cytokines TNF-α, IL-6,IL-4, and IL-10 in bacterial pharyngotonsillitis caused by group A and non-A (groups B, C, F and G) β-hemolytic streptococcus.METHODS: The study was conducted at a pediatric emergency care unit. The sample comprised children (5-9 years old) with acute bacterial pharyngotonsillitis diagnosed between December of 2011 and May of 2012. The research involved collection of blood samples from the patients, enzyme-linked immunosorbent assay detection of TNF-α, IL-6,IL-4, and IL-10, and collection of two oropharyngeal swabs for bacterial isolation. Additionally, the medical history of the study participants was also collected.RESULTS: In the studied group (mean age: 5.93 years), higher pharyngotonsillitis incidence was observed in the female gender (64.76%). Higher incidence of tonsillar exudates was observed with groups A and C. No statistically significant differences in cytokine levels were observed among groups. However, the group A and the control group showed a difference in the IL-6 level (p = 0.0016).CONCLUSIONS: The Groups A and C showed higher cytokine levels than the Groups B and control, suggesting similar immunological patterns.

INTRODUÇÃO: O patógeno mais comumente associado à faringotonsilite bacteriana é o estreptococo β-hemolítico do grupo A, a despeito dos grupos B, C, F e G terem também sido associados com a faringotonsilite.OBJETIVO: Determinar os níveis das citosinas TNF-α, IL-6, IL-4, e IL-10 na faringotonsilite bacteriana causada pelos estreptococos β-hemolíticos do grupo A e não-A (grupos B, C, F e G).MÉTODO: O estudo foi conduzido em uma emergência pediátrica. A amostra estudada compreendeu crianças (entre 5 e 9 anos) com faringotonsilite aguda bacteriana diagnosticada entre dezembro de 2011 e maio de 2012. A pesquisa envolveu a coleta de amostras sanguíneas dos pacientes, a detecção, através do ELISA, de TNF-α, IL-6, IL-4, and IL-10, além da coleta de dois swabs orofaríngeos para isolamento bacteriano. Adicionalmente foi coletada a história médica dos participantes do estudo.RESULTADOS: No grupo estudado (idade média: 5,93 anos), a maior incidência de faringotonsilite foi observada no gênero feminino (64,76%). Foram detectadas maiores incidências de exsudatos tonsilares nos grupos A e C. Não foram observadas diferenças estatisticamente significantes dos níveis de citosinas entre os grupos. Porém os grupos A e o controle mostraram diferença nos níveis de IL-6 (p = 0.0016).CONCLUSÕES: Os grupos A e C mostraram maiores níveis de citosinas que os grupos B e o controle, sugerindo mecanismos imunológicos similares.

Evaluation of cytokines produced by ß-hemolytic streptococcus in acute pharyngotonsillitis.

INTRODUCTION: The most common pathogen in bacteria lpharyngotonsillitis is group A ß-hemolytic streptococcus, although groups B, C, F,and G have also been associated with pharyngotonsillitis. OBJECTIVE: To assess the levels of the cytokines TNF-α, IL-6,IL-4, and IL-10 in bacterial pharyngotonsillitis caused by group A and non-A (groups B, C, F and G) ß-hemolytic streptococcus. METHODS: The study was conducted at a pediatric emergency care unit. The sample comprised children (5-9 years old) with acute bacterial pharyngotonsillitis diagnosed between December of 2011 and May of 2012. The research involved collection of blood samples from the patients, enzyme-linked immunosorbent assay detection of TNF-α, IL-6,IL-4, and IL-10, and collection of two oropharyngeal swabs for bacterial isolation. Additionally, the medical history of the study participants was also collected. RESULTS: In the studied group (mean age: 5.93 years), higher pharyngotonsillitis incidence was observed in the female gender (64.76%). Higher incidence of tonsillar exudates was observed with groups A and C. No statistically significant differences in cytokine levels were observed among groups. However, the group A and the control group showed a difference in the IL-6 level (p=0.0016). CONCLUSIONS: The Groups A and C showed higher cytokine levels than the Groups B and control, suggesting similar immunological patterns.

The neutrophil function and lymphocyte profile of milk from bovine mammary glands infected with Streptococcus dysgalactiae.

Streptococcus dysgalactiae is a bacterium that accounts for a notable proportion of both clinical and subclinical intramammary infections (IMIs). Thus, the present study explores the function of milk neutrophils and the lymphocyte profile in mammary glands naturally infected with Streptococcus dysgalactiae. Here, we used 32 culture-negative control quarters from eight clinically healthy dairy cows with low somatic cell counts and 13 S. dysgalactiae-infected quarters from six dairy cows. Using flow cytometry, we evaluated the percentage of milk monocytes/macrophages and neutrophils, expression of CD62L, CD11b and CD44 by milk neutrophils, the levels of intracellular reactive oxygen species (ROS) production and phagocytosis of Staphylococcus aureus by milk neutrophils, and neutrophil viability. Furthermore, the percentages of B cell (CD21(+)) and T lymphocyte subsets (CD3(+)/CD4(+)/CD8(-); CD3(+)/CD8(+)/CD4(-); and CD3(+)/CD8(-)/CD4(-)), and the expression of CD25 by T milk lymphocytes (CD3(+)) and T CD4(+) milk cells were also assessed by flow cytometry using monoclonal antibodies. The present study showed a higher SCC and percentage of milk neutrophils, and a decrease in the percentage of milk monocytes/macrophages from S. dysgalactiae-infected quarters when compared to uninfected ones. We also observed a higher expression of CD11b by milk neutrophils and a tendency toward a decrease in neutrophil apoptosis rate in S. dysgalactiae-infected quarters. In addition, the S. dysgalactiae-infected quarters had higher percentages of milk T cells (CD3(+)) and their subset CD3(+)CD8(+)CD4(-) cells. Overall, the present study provided new insights into S. dysgalactiae IMIs, including distinct lymphocyte profiles, and a tendency toward an inhibition of apoptosis in milk neutrophils.