Bacteriemia por Streptococcus equi subespecie zooepidemicus en un binomio madre hijo / Streptococcus equi subspecies zooepidemicus bacteremia in a mother-child binomial

Resumen Streptococcus equi subespecie zooepidemicus es una cocácea grampositiva, p-hemolítica, considerada parte de la microbiota de los equinos y un patógeno oportunista en otros animales. La infección en humanos es poco frecuente, pero suele manifestarse como cuadros graves. Se ha asociado al contacto con animales, especialmente caballos, y al consumo de productos lácteos no pasteurizados. Presentamos el caso de una bacteriemia en un binomio madre-hijo por este agente, asociado al consumo de quesos artesanales. Pese a que la penicilina es el tratamiento de elección, la recién nacida fue tratada en forma exitosa con ampicilina y la madre con ceftriaxona. Ninguna de ellas presentó complicaciones asociadas a la bacteriemia. A nuestro conocimiento, este es el primer reporte de infección connatal por este agente.

Abstract Streptococcus equi subspecies zooepidemicus is a Gram-positive, P-hemolytic coccus considered part of the commensal flora in horses and an opportunistic pathogen in other animals. Infection in humans is rare, but it usually manifests as serious symptoms, it has been associated with contact with animals, especially horses, and the consumption of unpasteurized dairy products. In this report we describe a case of bacteremia of the mother-child binomial by this agent, associated with the consumption of artisan cheeses. Although penicillin is the treatment of choice, the newborn was successfully treated with ampicillin and the mother with ceftriaxone, none of them presented complications associated with bacteremia. To our knowledge, this is the first report of connatal infection by this agent.

Modelagem farmacocinética/farmacodinâmica do florfenicol para o tratamento da adenite equina por meio da simulação de Monte Carlo / Pharmacokinetic/pharmacodynamic modeling of florfenicol for the treatment of equine adenitis using Monte Carlo simulation

O objetivo deste trabalho foi avaliar a eficácia do florfenicol na dose usualmente empregada em equinos de 22 mg/kg pelas vias intravenosa, intramuscular e oral para o tratamento de adenite equina por Streptococcus equi. subsp. equi, usando a modelagem farmacocinética/farmacodinâmica (PK/PD – Pharmacokinetic/Pharmacodynamic) e a simulação de Monte Carlo. Foi realizada uma simulação de Monte Carlo a partir dos parâmetros PK, logo depois, efetuou-se a modelagem PK/PD para determinar as taxas de eficácia do antimicrobiano para o tratamento dessa infecção bacteriana, de acordo com o valor da concentração inibitória mínima (CIM), em um intervalo de CIM de 0,125 – 4 μg/mL. Pela via intravenosa, a probabilidade de erradicação bacteriana foi de 100% para CIM até 0,5 μg/mL e efeito bacteriostático com probabilidades de 99% e 80% para CIMs de 2 e 4 μg/mL, respectivamente. Já pelas vias intramuscular e oral a probabilidade de se atingir o índice de erradicação bacteriológica foi de 100% para CIM de até 0,5 μg/mL, contudo, atinge valores de 80% e 81%, respectivamente, para CIM de 1 μg/mL considerando o efeito bactericida (p<0,01). Portanto, através desse estudo é evidenciado a eficácia do florfenicol até a CIM de 0,5 μg/mL para as três vias de administração citadas, entretanto, para CIMs superiores a esse valor, é imprescindível o ajuste da dose farmacológica, evitando falhas na terapêutica e possível resistência microbiana.

The objective of this study was to evaluate the efficacy of florfenicol at the dose usually used in horses of 22 mg/kg by intravenous, intramuscular and oral routes for the treatment of equine adenitis caused by Streptococcus equi. subsp. equi, using Pharmacokinetic/Pharmacodynamic (PK/PD) modeling and Monte Carlo simulation. A Monte Carlo simulation was performed from the PK parameters, then PK/PD modeling was performed to determine the antimicrobial efficacy rates for the treatment of this bacterial infection, according to the minimum inhibitory concentration (MIC) value, in a MIC range of 0.125 - 4 μg/mL. Intravenously, the probability of bacterial eradication was 100% for MICs up to 0.5 μg/mL, and the bacteriostatic effect was 99% and 80% for MICs of 2 and 4 μg/mL, respectively. However, for the intramuscular and oral routes, the probability of reaching the bacteriologic eradication index was 100% for MICs of up to 0.5 μg/mL, however, it reaches values of 80% and 81%, respectively, for MICs of 1 μg/mL considering the bactericidal effect (p<0.01). Therefore, through this study the efficacy of florfenicol is evidenced up to the MIC of 0.5 μg/mL for the three routes of administration cited, however, for MICs higher than this value, it is essential to adjust the pharmacological dose, avoiding failures in therapy and possible microbial resistance.

Immunogenicity of Streptococcus equi subsp. equi recombinant SeM protein and bacterin in mice / Imunogenicidade da proteína recombinante SeM de Streptococcus equi subsp. equi e da bacterina em camundongos

The infection caused by Streptococcus equi, known as strangles, affects the respiratory system of horses, causing high morbidity and rapid spread among the herd. Bacterin vaccines, composed of inactivated whole cells of S. equi, have variable efficacy and duration. Infected animals produce specific antibodies against SeM, the immunodominant antigen of S. equi. This makes it a promising target for vaccine development. In this context, the objective of this work was to evaluate a vaccine combining S. equi bacterin and recombinant SeM protein. Mice were vaccinated with bacterin (S. equi ~1.2 × 108CFU/ml); rSeM protein (20μg); bacterin-rSeM combination; or PBS (Control Group) and challenged with a suspension of S. equi, containing 10 × LD50. All vaccinated mice survived the challenge and produced anti-rSeM and anti-S. equi antibodies, which were assessed by indirect ELISA. The Control Group reached endpoint criteria 96 h after infection. These results demonstrate that a vaccine combining the S. equi bacterin with rSeM protein protects mice against strangles. This combination vaccine could potentially protect horses and overcome the limitations of currently available strangle vaccines.(AU)

A infecção causada por Streptococcus equi, denominada adenite, atinge o sistema respiratório de equinos, causando alta morbidade e rápida disseminação entre o rebanho. Vacinas bacterinas, compostas de células inteiras inativadas de S. equi apresentam eficácia e duração variáveis. Animais infectados apresentam anticorpos específicos à proteína SeM, antígeno imunodominante de S. equi, o que a torna um alvo promissor para o desenvolvimento de vacinas. Neste contexto, o objetivo deste trabalho foi avaliar uma vacina baseada na administração simultânea da bacterina e da proteína SeM recombinante. Camundongos foram vacinados com a bacterina (S. equi ~1.2 × 108CFU/ml); a proteína rSeM (20μg); a bacterina e rSeM simultaneamente; ou PBS (Grupo Controle) e, posteriormente, foram desafiados com uma suspensão de S. equi contendo 10 × LD50. Todos os animais vacinados apresentaram anticorpos anti-rSeM e contra S. equi, avaliados através de ELISA indireto, e mantiveram-se e sobreviveram ao desafio letal. O Grupo Controle atingiu critérios de endpoint 96 h após a infecção. Estes resultados demonstram que uma vacina constituída de células inteiras de S. equi com rSeM protege camundongos contra adenite, sugerindo a capacidade de proteção a equinos e, possivelmente, superando as limitações das vacinas contra adenite atualmente disponíveis.(AU)

Films Based on Blends of Polyvinyl Alcohol and Microbial Hyaluronic Acid

Abstract The aims of this work were to produce hyaluronic acid (HA) by Streptococcus zooepidemicus ATCC 39920 in a low cost sugarcane molasses fermentation medium and to employ the produced HA to obtain films blends based on polyvinyl alcohol (PVA). The films were produced using solution casting method and they were characterized according to their microstructure, mechanical and barrier properties. HA was added in different concentrations (0, 5, 10 and 15% (w/w)), and glycerol was used as a plasticizer (25 g/100 g solids). All formulations resulted in easily manipulated films with good appearance. The addition of HA on PVA films increased their thermal stability, solubility, swelling index, water vapor permeability and elongation. Microbial HA sample combined with PVA showed to be a promising material to biomedical application, and an addition between 5 and 10% (w/w) was sufficient to improve PVA films properties.

Cervical vertebral osteomyelitis secondary to Streptococcus equi infection in an adult horse - case report / Osteomielite vertebral cervical secundária à infecção por Streptococcus equi em um cavalo adulto - relato de caso

A 15-year-old, mixed breed, male horse was attended with a history of multiple abscesses in the cervical region with a three-year evolution. Upon admission, three fistulous tracts with drainage of purulent secretions in the cervical region, low body score, restriction of cervical movements, and painful sensitivity to palpation were observed. The horse was diagnosed with osteomyelitis secondary to Streptococcus equi infection. The initial treatment was antibiotic therapy and local curative. Owing to the lack of response, surgical debridement was performed. An initial favorable response was observed; however, after 4 months, drainage recurred, and the animal was euthanized. A post-mortem computed tomography scan was performed to obtain details of the injury. Cervical osteomyelitis is rare, and its occurrence through hematogenous spread in adult horses and the tomographic findings had not been reported previously. The long period of evolution, difficulty in performing an aggressive debridement, and the presence of multi-drug resistant bacteria contributed to the negative outcome.(AU)

Um equino macho, sem raça definida, de 15 anos de idade, foi atendido com histórico de múltiplos abscessos cervicais com evolução de três anos. Na admissão, foram observados: três trajetos fistulosos com drenagem de material purulento na região cervical; baixo escore corporal; restrição de movimentos cervicais; e sensibilidade dolorosa à palpação da região. Foi diagnosticada osteomielite vertebral cervical secundária à infecção por Streptococcus equi. O tratamento inicial consistiu na administração de antibióticos e curativo local. Na ausência de resposta à terapia, realizou-se o debridamento cirúrgico. Inicialmente, obteve-se uma resposta favorável, entretanto, após quatro meses, houve recidiva da lesão e o animal foi submetido à eutanásia. Realizou-se tomografia computadorizada no post mortem para detalhamento da lesão. A osteomielite vertebral cervical é rara, e sua ocorrência por meio de disseminação hematógena em animais adultos não foi previamente reportada. O longo período de evolução, aliado à dificuldade de realização de um debridamento agressivo, e a característica multirresistente do agente etiológico contribuíram para o desfecho negativo do caso.(AU)

Artritis séptica por Streptococcus equi: reporte de un caso y revisión de la literatura / Septic arthritis due to Streptococcus equi: a case report and review of the literatura

En humanos las infecciones producidas por Streptococcus equi son de rara ocurrencia, tienen una amplia variedad de formas de presentación, incluyendo compromiso articular, el cual ha sido pocas veces descrito en humanos y aún menos en pacientes inmunocompetentes. En este artículo se presenta un caso de artritis séptica por S. equi que ocurrió por una exposición ocupacional en un paciente inmunocompetente y la revisión de la literatura relacionada.

Human infections caused by Streptococcus equi are rare, have a wide variety of forms of presentation, including joint involvement, which has been rarely described in humans and even less in immunocompetent patients. In this article we present a septic arthritis case due to S. equi that occurred due to an occupational exposure in an immunocompetent patient, and a review of the related literature as well. The publication of this case report was accepted by the institutional ethics committee and the consent signed by the patient was obtained.

Construction of engineered Streptococcus zooepidemicus for the production of hyaluronic acid ligosaccharide / 生物工程学报

Hyaluronic acid (HA) is widely used in many fields, such as medicine, cosmetics and food. The bioactivity of HA depends on its molecular weight (Mw). Owing to the important physiological activities and special physiological functions, HA oligosaccharides have important application prospects in medicine fields. Streptococcus zooepidemicus has wide applications in commercial production of HA, due to its short fermentation cycle and strong production intensity. In order to efficiently synthesize HA oligosaccharides and solve the dissolved oxygen in the fermentation process, in this study, we overexpressed HA synthase (HasA) and introduced and optimized the leech hyaluronidase LHAase in Streptococcus zooepidemicus WSH-24. As a result, HA oligosaccharides were efficiently produced with improved dissolved oxygen. After 24 h, HA oligosaccharides production intensity reached to 294.2 mg/(L·h), and the concentration accumulated to 0.97 g/L in flask cultures, which was 1.82 times of the wild strain. Impressively, HA oligosaccharides were increased to 7.06 g/L in 3 L fermentor. The constructed Streptococcus zooepidemicus strain for producing HA oligosaccharides would have broad application prospects.

Lung lesions of slaughtered horses in southern Brazil / Lesões pulmonares de equinos de matadouro-frigorífico no Sul do Brasil

Respiratory diseases cause significant veterinary costs, reduce performance and require withdrawal of horses. Yet, studies of the causes of pneumonia in horses are scant. This study aimed to describe the pathological and microbiological features of lung lesions in slaughtered horses in southern Brazil. In this study, 84 samples of lungs were examined, and a conclusive diagnosis was obtained in 74 cases. These were composed of bronchopneumonia in 50 cases, followed by granulomatous eosinophilic pneumonia (9/74), recurrent airway obstruction (7/74), lung fibrosis (4/74), lung hemorrhage (3/74) and pulmonary pythiosis (1/74). Bronchopneumonia had grossly firm focally extensive yellow to dark-red areas, which consisted microscopically of multifocal to coalescing infiltrate of degenerate neutrophils. Streptococcus equi subsp. zooepidemicus was identified in 21 of the 50 cases. Granulomatous eosinophilic pneumonia had multifocal pinpoint firm-hard yellow areas, which microscopically were composed of granulomas with a mineralized center surrounded by collagen fibers and severe infiltrate of eosinophils. Recurrent airway obstruction had mild multifocal pinpoint firm white areas that consisted microscopically of large amounts of mucus inside bronchi and bronchiole. Lung fibrosis had two patterns: focally extensive areas of consolidation and firm nodular areas. Microscopically, the first pattern had interstitial to peribronchial fibrosis, while the second had, in addition to the interstitial fibrosis, a severe pneumocyte hyperplasia and an alveolar infiltrate of neutrophils and macrophages with rare intranuclear inclusion bodies (equine herpesvirus 5, EHV-5). Pulmonary pythiosis presented a focal firm nodular area, with multiple kunkers observed in the cut surface, which corresponded microscopically to areas of necrosis surrounded by a mixed inflammatory infiltrate. At the periphery of the necrotic areas, multiple negatively stained hyphae were observed, which were evidenced through Grocott's stain and immunohistochemistry anti-Pythium insidiosum.(AU)

Doenças respiratórias causam em equinos custos significativos com tratamento veterinário, redução de performance e descarte de animais. No entanto, estudos que abordem as causas de pneumonia em equinos são escassos. O objetivo deste estudo foi descrever os aspectos patológicos e microbiológicos de lesões pulmonares em equinos abatidos em matadouro-frigorífico no Sul do Brasil. Neste estudo, 84 amostras de pulmões foram examinadas, e o diagnóstico conclusivo das condições foi obtido em 74 casos. Esses foram compostos por broncopneumonia em 50 casos, seguido por pneumonia granulomatosa eosinofílica (9/74), obstrução aérea recorrente (7/74), fibrose pulmonar (4/74), hemorragia pulmonar (3/74) e pitiose pulmonar (1/74). A broncopneumonia era caracterizada macroscopicamente por áreas focalmente extensas firmes de coloração amarelada a vermelho-escuras, as quais consistiam microscopicamente em infiltrado multifocal a coalescente de neutrófilos degenerados. Streptococcus equi subsp. zooepidemicus foi identificado em 21 dos 50 casos. A pneumonia eosinofílica granulomatosa era caracterizada por áreas multifocais puntiformes firmes a duras e amareladas, que microscopicamente eram compostas por granulomas com área central mineralizada circundados por fibras de colágeno e infiltrado acentuado de eosinófilos. A obstrução aérea recorrente era caracterizada por discretas áreas puntiformes firmes e brancacentas que consistiam microscopicamente em grande quantidade de muco no interior de brônquios e bronquíolos. A fibrose pulmonar exibia dois padrões: áreas de consolidação focalmente extensas e áreas nodulares firmes. Microscopicamente, o primeiro padrão exibia fibrose intersticial a peribronquial, enquanto no segundo padrão havia, além da fibrose intersticial, intensa hiperplasia de pneumócitos e infiltrado alveolar de neutrófilos e macrófagos com raros corpúsculos de inclusão intranucleares (herpesvírus equino 5, EHV-5). A pitiose pulmonar exibia uma área nodular firme focal com múltiplos kunkers ao corte, os quais correspondiam microscopicamente a áreas de necrose circundadas por infiltrado inflamatório misto. À periferia das áreas necróticas, múltiplas imagens negativas de hifas eram observadas, as quais foram evidenciadas através da coloração de Grocott e imuno-histoquímica anti-Pythium insidiosum.(AU)

Sensibilidad a los antimicrobianos de aislamientos de Streptococcus equi subsp. equi de la provincia de Buenos Aires, Argentina / Antimicrobial susceptibility in isolates of Streptococcus equi subsp. equi from Buenos Aires province, Argentina

Streptococcus equi subsp. equi es el agente etiológico de la adenitis equina, una enfermedad infecciosa que afecta al tracto respiratorio superior y linfonódulos de cabeza y cuello de equinos. La terapia antimicrobiana tradicional incluye como antibiótico de primera elección a la penicilina G (PEN), a la que los estreptococos suelen ser sensibles. El objetivo de este trabajo fue estudiar el perfil de sensibilidad a distintos antimicrobianos de cepas de S. equi que circulan en la provincia de Buenos Aires, Argentina. Se estudiaron 92 aislamientos mediante el método de difusión con discos; los antimicrobianos evaluados fueron PEN, cefotaxima, eritromicina, tetraciclina, enrofloxacina (ENR), trimetroprima-sulfametoxazol (TMS), ciprofloxacina, clindamicina (CLI), estreptomicina (STR) y florfenicol. Se determinó la concentración inhibitoria mínima (CIM) de la PEN y de aquellos antimicrobianos frente a los cuales S. equi mostró resistencia o sensibilidad intermedia. Se obtuvieron altos porcentajes de sensibilidad a todos los antimicrobianos por el método de difusión y valores de CIM por debajo de los puntos de corte para PEN, TMS y CLI. Se identificaron cepas resistentes a ENR y STR, con CIM50, CIM9o y rangos de CIM por encima de los puntos de corte. Los resultados confirman que la PEN podría utilizarse empíricamente, ya que las cepas circulantes en Buenos Aires no mostraron resistencia a este antimicrobiano. Se enfatiza en la relevancia del uso racional de los antibióticos para lograr éxito terapéutico, evitar la cronicidad, la recidiva de infecciones y la aparición de resistencia.

Streptococcus equi subsp. equi is the etiologic agent of strangles, an infectious disease affecting the upper respiratory tract and head and neck lymph nodes of equines. Routine antimicrobial therapy includes penicillin (PEN) as antibiotic of first choice. Streptococci are usually susceptible to PEN and only a few antimicrobial studies had been performed. The aim of this work was to study the antimicrobial susceptibility profile of S. equi from Buenos Aires, Argentina. Ninety-two isolates were studied by the single disk method to PEN, cefotaxime, erythromycin (ERY), tetracycline, enrofloxacin (ENR), trimethoprim sulfamethoxazole (TMS), ciprofloxacin, clindamycin (CLI), streptomycin (STR) and florfenicol. Minimum inhibitory concentration (MIC) to PEN and antibiotics with resistance and intermediate susceptibility were tested. High percentages of susceptibility were obtained by the disk diffusion method and MIC values of PEN, TMS and CLI were found to be under the breakpoint values. Resistant strains of ENR and STR with MIC50, MIC90 and MIC ranges above breakpoints were identified. These findings confirm that PEN may be used empirically because resistant strains were not found in Buenos Aires. Emphasis is placed on the rational use of antibiotics to achieve therapeutic success, to prevent chronicity, recurrence of infections and the emergence of resistance.

Imunogenicidade da proteína M recombinante de Streptococcus equi subsp. equi coadministrada com um adjuvante molecular / Immunogenicity of recombinant M protein of Streptococcus equi subsp. equi co administered with a molecular adjuvant

The strangles is an infectious disease that affects horses from all ages and causes important economic losses in the equine-related business. The aim of this work was to evaluate the immunogenicity of the recombinant M protein from Streptococcus equi (rSeM) co-administered with the recombinant heat-labile enterotoxin B subunit from Escherichia coli (rLTB) in mice and horses. A total of 72 female Balb-c mice were divided into eight groups and 18 horses were divided into six groups. The animals were inoculated by intramuscular (IM) or intranasal (IN) routes with different treatments of rSeM, rLTB and/or Al(OH)3. The results obtained in both species, independent of administration routes, demonstrated that rSeM + rLTB had higher levels of specific serum immunoglobulins, however, in mucosal immunity the increase was not identified. Thus, the use of rSeM as vaccine antigen and rLTB as adjuvant can be a potential tool in the control of equine strangles.(AU)

Epidemia de nefrite por Streptococcus equi subsp. zooepidemicus: estudo de caso-controle no município de Monte Santo de Minas, Minas Gerais, 2013 / Outbreak of nephritis by Streptococcus equi subspecies zooepidemicus: case-control study in the municipality of Monte Santo de Minas, Minas Gerais, Brazil, 2013 / Epidemia de nefritis por Streptococcus equi subsp. zooepidemicus: estudio de casos y controles en Monte Santo de Minas, Minas Gerais, Brasil, 2013

OBJETIVO: investigar a epidemia de nefrite por Streptococcus zooepidemicus em Monte Santo de Minas, Minas Gerais, Brasil. MÉTODOS: realizou-se estudo de caso-controle e tentativa de isolamento do agente, no período de janeiro a abril de 2013, utilizando-se dados clínicos, laboratoriais, de entrevistas e de inspeções. RESULTADOS: houve 417 casos notificados e 175 (42,0%) confirmados, dos quais 90,9% residiam no município e 67,4% eram do sexo feminino, com idade mediana de 36 anos; 24% dos casos foram hospitalizados; três sorveterias do município utilizavam leite do laticínio A; houve associação significativa entre adoecimento e consumo do leite A (odds ratio [OR]=4,16/IC95%: 1,55;11,18), um dos sorvetes feito com esse leite (OR=3,09/IC95%: 1,39;6,86) e milk shake de leite não industrializado (OR=3,25/IC95%: 1,13;9,36); não se detectou a bactéria em propriedades rurais. CONCLUSÃO: a epidemia de nefrite por Streptococcus zooepidemicus foi associada ao consumo de leite e derivados.

OBJECTIVE: to investigate an outbreak of nephritis by Streptococcus zooepidemicus in Monte Santo de Minas, Minas Gerais State, Brazil. METHODS: a case-control study and attempt to isolate the bacterial agent were carried out from January to April 2013, using clinical and laboratory data, interviews and inspections. RESULTS: 417 suspected cases were reported, of which 175 (42.0%) were confirmed; 90.9% lived in that municipality, of which 67.4% were female, with median age of 36 years; 24% of cases were hospitalized; three ice cream shops in the municipality used type A milk; there was significant association between the illness and the consumption of type A milk (odds ratio [OR]=4.16/95%CI: 1.55;11.18), one of the ice cream made with this milk (OR=3.09/95%CI: 1.39;6.86) and milk shake of non-processed milk (OR=3.25/95%CI: 1.13;9.36); the bacterium was not detected in rural properties. CONCLUSION: the outbreak of nephritis by Streptococcus zooepidemicus was associated with the consumption of milk and dairy products.

OBJETIVO: investigar la epidemia de nefritis por Streptococcus zooepidemicus en Monte Santo de Minas, Minas Gerais, Brasil. MÉTODOS: fue realizado un estudio de casos y controles e intento de aislamiento del agente, entre enero y abril de 2013, con datos clínicos y de laboratorio, entrevistas e inspecciones. RESULTADOS: fueron notificados 417 casos sospechoso, de los cuales, 175 confirmados; 90,9% eran residentes del municipio, 67,4% de sexo femenino, con mediana de edad de 36 años; 24% casos fueron hospitalizados; tres heladerías del municipio utilizaban leche del lacticinio A; encontramos asociación significativa entre la enfermedad y el consumo de leche A (odds ratio [OR]=4,16/IC95%: 1,55;11,18), en helados hechos con leche (OR=3,09/IC95%: 1,39;6,86) y milk shake de leche no industrializada (OR=3,25/IC95%: 1,13;9,36); la bactéria no fue aislada en zonas rurales. CONCLUSIÓN: la epidemia de nefritis por Streptococcus zooepidemicus se asoció con el consumo de leche y derivados.

Prokaryotic expression and immunogenicity of IgG-binding protein of Streptococcus equi subspecies equi / 生物工程学报

To analyze the immunogenicity and protective ability of recombinant IgG-binding protein (EAG) of Streptococcus equi subspecies equi and to evaluate its value when used as equine vaccine antigen, EAG gene was amplified by PCR and inserted into pET-28a vector. The EAG recombinant proteins were expressed and purified to immune mice. The serum antibody and challenge protection were tested. The purified recombinant protein of EAG was 26 kDa, and the protein reacted specifically with positive serum of Streptococcus equi subspecies equi. The mice antibody level for EAG immunization group was 1∶8 100. The immunological protection result showed that the protection rate of the EAG recombinant protein was 90%. The results suggested that the EAG protein has good immunogenicity and immunological protection, and it can effectively increase the humoral immune response and immunological protection of mice.

Maturidade de potros nascidos de éguas com placentite / Maturity of foals from the mares with placentitis

Objetivou-se descrever a maturidade neonatal através da resposta clínica, comportamental e hematológica de potros nascidos de éguas com placentite. Participaram do estudo seis potros nascidos de éguas submetidas à indução experimental de placentite ascendente através da infusão intracervical de Streptococcus equi subespécie zooepidemicus e tratadas com Sulfa-trimetoprim e Flunixin meglumine. A formação dos grupos neonatais foi realizada de acordo com o grau de viabilidade e sobrevivência até 60 horas: Grupo Não Sobreviventes (n=2); Grupo Debilitados (n=2); Grupo Saudáveis (n=2). Foi considerado o tempo de gestação, período de intervalo inoculação-parto, avaliação comportamental, clínica e hematológica. O Grupo dos potros Saudáveis apresentou maior tempo de gestação (320±2 dias) e maior intervalo inoculação-parto (20,5±2,5 dias). Os Grupos Não Sobreviventes e Debilitados apresentaram atraso para decúbito esternal e reflexo de sucção. Foi observada bradicardia e hipotermia com 48h de vida no Grupo Não Sobreviventes. Os potros do Grupo Não Sobreviventes e Saudáveis apresentaram leucopenia no nascimento com discretas variações até as 48h. Os potros nascidos de éguas com placentite ascendente e tratadas demonstraram evolução clínica e respostas neonatais distintas. Conclui-se que, quanto maior o tempo de manutenção da gestação após a injúria placentária, melhor será a maturação fetal, o que refletirá em viabilidade e melhor capacidade de resposta neonatal...

The aim of this study was to describe the neonatal maturity through clinical, behavioral and hematologic response of foals born from mares with placentitis. Were used six foals born from mares subjected to experimentally induced ascending placentitis through intracervical infusion of Streptococcus equi subspecies zooepidemicus and treated with trimethoprim sulfametoxazole and flunixin meglumine. The neonatal groups were performed according to the viability and survival rate up to 60 hours: No Survivors group (n = 2); Debilitated group (n = 2); Healthy group (n = 2). Gestational length, the period between inoculation and delivery, and behavioral, clinical and hematologic evaluations were considered. The Healthy group showed longer gestation length (320±2 days) and longer inoculation-delivery interval (20.5±2.5 days). No Survivors and Debilitated groups showed delay in sternal recumbency and sucking reflex. Bradycardia and hypothermia was observed at 48 hours of life in No Survivors Group. Foals from No Survivors and Healthy groups showed leukopenia at birth with slight variations until 48h. Foals born from mares with ascending placentitis and treated showed distinct clinical and neonatal responses. It is concluded that the longer the maintenance of gestation after placental injury, better is the fetal maturation, which reflects in better viability and ability to neonatal response...

Cloning, expression and characterization of SeM protein of Streptococcus equi subsp. equi and evaluation of its use as antigen in an indirect ELISA / Clonagem, expressão e caracterização de proteína SeM de Streptococcus equi subsp. equi e avaliação de sua utilização como antígeno em um ELISA indireto

Strangles is an economically important horse disease caused by Streptococcus equi subsp. equi. The diagnosis can be confirmed either directly by bacterial isolation and PCR or by ELISA, which is an indirect method based on the detection of serum antibodies. The aim of this study was to clone, express and characterize the SeM protein of Streptococcus equi subsp. equi, evaluate its use as antigen in indirect ELISA and determine its performance to distinguish sera of negative, vaccinated and positive animals. This was initially performed by cloning the gene encoding the SeM protein and its expression in Escherichia coli. Subsequently, the protein produced was characterized and used as antigen in ELISA. Serum samples for evaluation were taken from 40 negative foals, 46 horses vaccinated with a commercial vaccine against strangles and 46 horses diagnosed with the disease. The test showed high specificity and sensitivity, allowing discrimination between negative and positive, positive and vaccinated animals, and vaccinated animals and negative sera. Thus, it was concluded that the protein produced rSeM, which can be used as antigen for disease diagnosis, and the described ELISA might be helpful to evaluate the immune status of the herd...

A adenite equina é uma enfermidade economicamente importante de equinos, causada por Streptococcus equi subsp. equi. Seu diagnóstico pode ser confirmado de forma direta, por meio de isolamento bacteriano e de PCR, ou de forma indireta, por meio de ELISA, método baseado na detecção de anticorpos séricos. O objetivo deste estudo foi clonar, expressar e caracterizar a proteína SeM de Streptococcus equi subsp. equi, avaliar sua utilização como antígeno em um ELISA indireto e determinar a capacidade do teste de distinguir soros de animais negativos, vacinados e positivos. Para tal, foi inicialmente realizada a clonagem do gene que codifica para a proteína SeM e sua expressão em Escherichia coli. Posteriormente, a proteína produzida foi caracterizada e utilizada como antígeno em um teste de ELISA indireto. Para avaliação do teste, foram utilizadas amostras de soro de 40 potros negativos, de 46 equinos vacinados com uma vacina comercial contra adenite equina e de 46 equinos com diagnóstico da doença. O teste demonstrou alta sensibilidade e especificidade, permitindo discriminar entre soros negativos e positivos, positivos e de animais vacinados, e negativos e de animais vacinados. Assim, conclui-se que a proteína rSeM produzida pode ser usada como antígeno para o diagnóstico da enfermidade e que o ELISA descrito pode ser útil para avaliar o estado imunológico do rebanho...

Celulitis por Streptococcus equi: reporte de caso y revisión de la literatura / Streptococcus equi Cellulitis: Case Report and Literature Review

El Streptococcus equi es un coco gram positivo, perteneciente al grupo C de Lancefield, causa una enfermedad de gran relevancia en caballos, la gurma o adenitis equina (1-2); en humanos, estas infecciones son poco frecuentes, siendo más frecuentes las infecciones de piel y tejidos blandos, faringitis, neumonía, síndrome tóxico similar al shock y endocarditis. Cuando la infección está asociada a bacteriemia, la mortalidad reportada es del 25%.(3) Presentamos el caso de un hombre de 44 años que ingresa al servicio de urgencias de la Clínica universidad de la Sabana con un cuadro clínico de celulitis en mano derecha por Streptococcus equi .

Streptococcus equi is a gram-positive cocci, from group C of Lance 􀃀 eld. It causes an important disease in horses, strangles or equine adenitis (1-2). In humans, these infections are rare, and skin and soft tissue infections, pharyngitis, pneumonia, toxic shock-like syndrome and endocarditis are more frequently observed. When the infection is associated with bacteremia, the reported mortality is near 25% (3). We report the case of a 44-year old man who was admitted to the emergency department of the University of Sabana Clinic with cellulitis due to Streptococcus equi in his right hand.

Optimization of flask culture medium and conditions for hyaluronic acid production by a streptococcus equisimilis mutant nc2168

A mutant designated NC2168, which was selected from wild-type Streptococcus equisimilis CVCC55116by ultraviolet ray combined with60Co-γ ray treatment and does not produce streptolysin, was employed to produce hyaluronic acid (HA). In order to increase the output of HA in a flask, the culture medium and conditions for NC2168 were optimized in this study. The influence of culture medium ingredients including carbon sources, nitrogen sources and metal ions on HA production was evaluated using factional factorial design. The mathematical model, which represented the effect of each medium component and their interaction on the yield of HA, was established by the quadratic rotary combination design and response surface method. The model estimated that, a maximal yield of HA could be obtained when the concentrations of yeast extract, peptone, glucose, and MgSO4 were set at 3 g/100 mL, 2 g/100 mL, 0.5 g/100 mL and 0.15 g/100 mL, respectively. Compared with the values obtained by other runs in the experimental design, the optimized medium resulted in a remarkable increase in the output of HA and the maximum of the predicted HA production was 174.76 mg/L. The model developed was accurate and reliable for predicting the production of HA by NC2168.Cultivation conditions were optimized by an orthogonal experimental design and the optimal conditions were as follows: temperature 33ºC, pH 7.8, agitation speed 200 rpm, medium volume 20 mL.

Perfil fenotípico e susceptibilidade antimicrobiana de Streptococcus equi isolados de equinos da região Sul do Brasil / Phenotypic profile and antimicrobial susceptibility of Streptococcus equi isolated from horses in southern Brazil

As características fenotípicas [morfológicas, bioquímicas, susceptibilidade aos antimicrobianos, índice de resistência múltipla aos antimicrobianos (IRMA), concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM) da benzilpenicilina] de 38 isolados de Streptococcus equi oriundos de amostras clínicas de animais com adenite equina foram alvo deste estudo. A fenotipia demonstrou três padrões de colônias, três biotipos de fermentação de carboidratos e variação de 0 a 0,4 no IRMA. Todos os isolados de S. equi demonstraram sensibilidade à penicilina, tanto pelo método de disco difusão quanto pelo método de microdiluição. A CIM e CBM média de benzilpenicilina foi de 0,0095μg/mL e 0,0267μg/mL para S. equi subesp. equi e de 0,0128μg/mL e 0,0380μg/mL para S. equi subesp. zooepidemicus. Os valores de CIM e CBM diferiram entre as subespécies (p<0,05). O diâmetro do halo de inibição de penicilina demonstrou relação com a CIM (ì=0,03638 - 0,00072x) para S. equi subesp. equi. Também foi demonstrada relação entre o diâmetro do halo de inibição de penicilina com a CBM para S. equi subesp. equi (ì=0,10931- 0,00223x). Entretanto para as amostras de S. equi subesp. zooepidemicus esta relação somente foi verificada para a CBM (ì=0,1322 - 0,00271x). A CIM de benzilpenicilina frente às amostras isoladas da região Central, Planalto e Sul do estado do Rio Grande do Sul foram estatisticamente semelhantes, mas diferiram do isolado do estado do Paraná, sugerindo o caráter atípico desta cepa. Todos os isolados de S. equi são sensíveis à penicilina e sulfazotrim, confirmando a eleição destes antimicrobianos para o tratamento das infecções por este agente na clínica veterinária. Os resultados obtidos não dispensam a utilização prudente dos antimicrobianos.

Phenotypic characteristics [morphology, biochemical fermentation, antimicrobial susceptibility, index of multiple resistances to antimicrobials (IMRA), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of benzilpenicillin] of 38 Streptococcus equi isolates from clinical samples of horses with strangles were the aim of this study. The phenotypic analyses demonstrated three colony patterns, three carbohydrate fermentation biotypes and IMRA variation from 0 to 0.4. All the isolates of S. equi demonstrated sensitivity to penicillin, both by the disc diffusion method and microdilution method. The average MIC and MBC for benzilpenincillin were of 0.0095μg/mL and 0.0267μg/mL for S. equi subsp. equi and of 0.0128μg/mL and 0.0380μg/mL for S. equi subsp. zooepidemicus. The values of MIC and MBC differed between the subspecies (p<0.05). The diameter of penicillin inhibition halo demonstrated a relation with the MIC (ì=0.03638 - 0.00072x) for Streptococcus equi subsp. equi. A relation between the diameter of the inhibition halo of penincillin was also observed with the MBC for S. equi subsp. equi (ì=0.10931 - 0.00223x). However for the samples of S. equi subsp. zooepidemicus this relation was only verified with the MBC (ì=0.1322 - 0.00271x). The MIC of benzilpenicillin of the samples isolated from the Central, Planalto and South regions of Rio Grande do Sul were statistically similar, although different from the Paraná state sample, suggesting the atypical character of this strain. All the S. equi isolates are sensitive to penicillin and sulfazotrim, confirming these as antibiotics of choice for the treatment of infections caused by this agent in the clinical veterinary practice. The results obtained do not discard the prudent use of antimicrobials.

Immunogenicity and cross reactivity indices of Streptococcus equi subsp. equi strains isolated from cases of Strangles and commercial vaccines / Imunogenicidade e índices de reatividade cruzada de cepas de Streptococcus equi subsp. equi isoladas de casos de Adenite Eqüina e vacinas comerciais

Horse Strangles appears frequently in animals vaccinated with commercial bacterins in Rio Grande do Sul, Brazil. Aiming to know the antigenic relationships of strains recovered from sick animals among them and with two vaccines profusely used in the state, bilateral cross reactivity indices (CRI) were estimated. In addition, the immunogenicity of vaccines prepared with field isolates and commercial vaccines was tested in mice. Antibody titers were measured by ELISA and expressed as seroconversions. Thirteen strains of Streptococcus equi subsp. equi, nine classified biochemically as typical and other four as atypical strains, were recovered from 35 sick horses belonging to 10 herds of Rio Grande do Sul, Brazil. The strains recovered from sick horses showed very close CRI, suggesting antigenic homogeneity among them, but not with the vaccinal strains. A vaccine produced with an atypical strain induced the highest seroconversion, 9.4, while two produced with typical strains were poorly-immunogenic. The commercial vaccines were less immunogenic than five and four vaccines produced with field strains, inducing seroconversions of 2.6 and 3.8, respectively.

A Adenite Eqüina é freqüente em animais vacinados com bacterinas comerciais no Rio Grande do Sul. Com o objetivo de determinar as relações antigênicas entre cepas isoladas de casos clínicos e duas vacinas amplamente utilizadas no Estado, foram determinados os índices de reatividade cruzada bilateral (IRC) entre elas. Também foi determinada a imunogenicidade em camundongos de vacinas preparadas com cepas de campo e de vacinas comerciais. Os títulos de anticorpos foram determinados por ELISA e expressos como soroconversão. Foram isoladas 13 cepas de Streptococcus equi subsp. equi de 35 casos clínicos de Adenite Eqüina em 10 diferentes rebanhos do Rio Grande do Sul, Brasil, das quais nove foram classificadas bioquimicamente como típicas e outras quatro como atípicas. As cepas de campo apresentaram elevada reatividade cruzada, sugerindo homogeneidade antigênica entre elas, mas não com as cepas vacinais. Uma vacina produzida com cepa atípica induziu soroconversão de 9.4, enquanto duas vacinas produzidas com cepas típicas foram pouco imunogênicas. As vacinas comerciais induziram soroconversões de 2.6 e 3.8, menores que quatro e cinco vacinas produzidas com cepas de campo, respectivamente.