RESUMO
We describe microbiological, clinical and epidemiological aspects of a diphtheria outbreak that occurred in Maranhão, Brazil. The majority of the 27 confirmed cases occurred in partially (n = 16) or completely (n = 10) immunized children (n = 26). Clinical signs and characteristic symptoms of diphtheria such as cervical lymphadenopathy and pseudomembrane formation were absent in 48% and 7% of the cases, respectively. Complications such as paralysis of lower limbs were observed. Three cases resulted in death, two of them in completely immunized children. Microbiological analysis identified the isolates as Corynebacterium diphtheriae biovar intermedius with a predominant PFGE type. Most of them were toxigenic and some showed a decrease in penicillin G susceptibility. In conclusion, diphtheria remains endemic in Brazil. Health professionals need to be aware of the possibility of atypical cases of C. diphtheriae infection, including pharyngitis without pseudomembrane formation.
Assuntos
Difteria/epidemiologia , Surtos de Doenças , Adolescente , Adulto , Brasil/epidemiologia , Criança , Corynebacterium diphtheriae/efeitos dos fármacos , Difteria/tratamento farmacológico , Difteria/microbiologia , Difteria/patologia , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Adulto JovemRESUMO
INTRODUCTION: Despite the recent advances in diagnosis and treatment, mortality rates due to infective endocarditis (IE) remain high if not aggressively treated with antibiotics, whether or not associated with surgery. Data on the prevalence, epidemiology and etiology of IE from developing countries remain scarce. The aim of this observational, prospective cohort study was to report a 5-year experience of IE at two teaching hospitals in Rio de Janeiro, Brazil. MATERIAL AND METHODS: Demographical, anamnestic and microbiological characteristics of 71 IE patients were evaluated during the period of January 2009 to March 2013. RESULTS: The mean age of the IE patients was 49.8 ± 2.4 years, of which 41 (57.7%) were males. The median time between the onset of symptoms and diagnosis of IE was 35.8 ± 4.8 days. A total of 31 (43.6%) cases of community-acquired infective endocarditis (CAIE) and 40 (56.3%) cases of healthcare-acquired infective endocarditis (HAIE) were observed. Staphylococcus aureus (30%) was the predominant cause of IE. Streptococcus spp. (45.1 %) was the predominant cause of the CAIE while S. aureus (32.5%) and Enterococcus spp. (27.2 %) were the main etiological agents of HAIE. For 64 (90.1 %) patients with native valve endocarditis, the mitral valve was the most commonly affected (48.3%). The main source of IE in this cohort was intravascular catheter. The tricuspid valve and renal chronic insufficiency were more frequent in patients with HAIE than CAIE (p = 0.001). The risk factors associated with in-hospital mortality rate (46.4%) in IE patients were: age over 45 (OR 3.4; 95% CI 1.03-11.24; p = 0.04) and chronic renal insufficiency (OR 38.3; 95% CI 3.2-449.4; p = 0.004). CONCLUSIONS: At two main teaching hospitals in Brazil, Streptococcus spp. was the principal pathogen of CAIE while S. aureus and Enterococcus spp. were the most frequent causes of HAIE. IE remains a serious disease associated with high in-hospital mortality rate (46.6%); especially, in individuals over 45 years of age and with renal failure. Data suggest that early surgery may improve the outcome of IE patients.
Assuntos
Bactérias/isolamento & purificação , Infecções Bacterianas/mortalidade , Endocardite/mortalidade , Mortalidade Hospitalar , Adulto , Infecções Bacterianas/microbiologia , Brasil/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/mortalidade , Infecção Hospitalar/microbiologia , Infecção Hospitalar/mortalidade , Endocardite/microbiologia , Feminino , Hospitais de Ensino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de RiscoRESUMO
A fatal case of aortic valve endocarditis due to Abiotrophia defectiva was reported in Brazil. An overview of cases of endocarditis and other human infections related to A. defectiva in developing countries was also accomplished.
Assuntos
Abiotrophia/isolamento & purificação , Valva Aórtica/patologia , Endocardite Bacteriana/epidemiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Valva Aórtica/microbiologia , Brasil , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Países em Desenvolvimento , Endocardite Bacteriana/microbiologia , Evolução Fatal , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial agent of biopolymer-associated infections, and isolates of S. aureus can produce different virulence factors, including potent toxins. The biofilm formation and accumulation by certain international MRSA lineages were analysed, and the toxic shock syndrome-associated genes (tst, seb and sec) among these isolates were assessed. In addition, the presence of lukF-pv (encoding the F-subunit of Panton-Valentine leukocidin (PVL)) was investigated. Most of the MRSA isolates tested were capable of forming biofilm on polystyrene surfaces, but lacked the superantigen toxin genes that were tested. PVL was rarely detected among the hospital isolates analysed.
Assuntos
Biofilmes/crescimento & desenvolvimento , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/fisiologia , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Enterotoxinas/genética , Humanos , Leucocidinas/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Poliestirenos , Superantígenos/genéticaRESUMO
The species Streptococcus dysgalactiae was proposed to accommodate a heterogeneous group of streptococci associated with infections in animals and human beings. This taxon is now considered to include animal isolates of alpha-haemolytic group C streptococci, previously called S. dysgalactiae; animal and human isolates of beta-haemolytic group C streptococci, previously called 'S. equisimilis'; beta-haemolytic group L strains associated with infections in animals and, rarely, in humans; and beta-haemolytic group G strains isolated from humans. DNA-DNA reassociation experiments (hydroxyapatite method) and multilocus enzyme electrophoresis (MEE) were performed on reference strains and clinical isolates to determine the genetic relationships among these different phenotypic categories. DNA-DNA hybridization tests showed that they were related at the species level, despite the phenotypic and host heterogeneity. Both genotypic and phenotypic characterization indicated that S. dysgalactiae could be separated into two major sub-groups. The first sub-group contained alpha-haemolytic strains that showed levels of DNA relatedness with the type strain of S. dysgalactiae ranging from 84 to 90% and from 82 to 88% under optimal (55 degrees C) and stringent (70 degrees C) conditions, respectively. The second sub-group contained beta-haemolytic strains showing levels of relatedness ranging from 71 to 79% (55 degrees C) and from 62 to 73% (70 degrees C). Percentage divergence varied from 0.5 to 1.0% (alpha-haemolytic group) and from 2.0 to 3.5% (beta-haemolytic group). A dendrogram based on phenotypic similarity between the enzyme bands produced by MEE showed a Jaccard similarity coefficient of 0.45 between the subclusters formed by the two sub-groups. The results of phenotypic and genotypic characterization were consistent with a published proposal to divide S. dysgalactiae into two subspecies, S. dysgalactiae subsp. dysgalactiae and S. dysgalactiae subsp. equisimilis, with a few modifications.
Assuntos
Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Streptococcus/genética , Animais , Eletroforese , Enzimas/genética , Humanos , Hibridização de Ácido Nucleico , Fenótipo , Filogenia , Sorotipagem , Especificidade da Espécie , Streptococcus/isolamento & purificaçãoRESUMO
Whole-cell protein profiles obtained by SDS-PAGE were used in conjunction with physiological tests to differentiate strains of Streptococcus canis isolated from dogs. Fermentation of trehalose and lactose, aesculin hydrolysis together with production of beta-D-glucuronidase and alpha-D-galactosidase allowed the demonstration of nine different biotypes. However, visual analysis of the protein patterns and comparison by the coefficient of Dice showed minor differences in band patterns among strains. Only two different profiles were observed. Although a correlation between biotyping and protein profile has been found, this kind of analysis did not provide the basis for a typing method.
Assuntos
Proteínas de Bactérias/isolamento & purificação , Cães/microbiologia , Streptococcus/isolamento & purificação , Streptococcus/metabolismo , Animais , Técnicas de Tipagem Bacteriana , Eletroforese em Gel de Poliacrilamida , Esculina/metabolismo , Feminino , Fermentação , Glucuronidase/biossíntese , Hidrólise , Lactose/metabolismo , Masculino , Streptococcus/classificação , Trealose/metabolismo , alfa-Galactosidase/biossínteseRESUMO
The influence of the subminimal inhibitory concentrations (1/3 and 1/4 of the MIC) of penicillin on growth rate and on haemolysin production of a strain of group G Streptococcus was studied. It was shown that 1/3 of the MIC almost completely inhibited the bacterial growth, but it was not able to inhibit haemolysin activity in the culture supernate. The generation time of bacteria grown in 1/4 of the MIC was approximately twice longer than that of the control culture. In all cultures, the haemolysin, after being produced (or liberated), reached a peak and decreased to low levels, which could suggest that group G Streptococcus produces some end products of metabolism that are able to inhibit haemolysin activity.