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1.
J Pediatr ; 235: 284-287, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33974955

RESUMO

HACEK organisms (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella species) are rare causes of endocarditis. HACEK organisms are fastidious and may escape detection by culture techniques, but the use of molecular studies may aid diagnosis. A 10-year review of pediatric HACEK endocarditis cases at Texas Children's Hospital identified 10 patients, with 2 cases recognized by next-generation sequencing, highlighting potential benefits of these assays.


Assuntos
Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Adolescente , Antibacterianos/administração & dosagem , Ceftriaxona/administração & dosagem , Criança , Endocardite Bacteriana/tratamento farmacológico , Cardiopatias Congênitas/complicações , Humanos , Lactente , Kingella/isolamento & purificação , Masculino , Estudos Retrospectivos , Centros de Atenção Terciária
2.
BMC Oral Health ; 21(1): 248, 2021 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-33964928

RESUMO

BACKGROUND: Subgingival microbiome in disease-associated subgingival sites is known to be dysbiotic and significantly altered. In patients with rheumatoid arthritis (RA), the extent of dysbiosis in disease- and health-associated subgingival sites is not clear. METHODS: 8 RA and 10 non-RA subjects were recruited for this pilot study. All subjects received full oral examination and underwent collection of subgingival plaque samples from both shallow (periodontal health-associated, probing depth ≤ 3mm) and deep subgingival sites (periodontal disease-associated, probing depth ≥ 4 mm). RA subjects also had rheumatological evaluation. Plaque community profiles were analyzed using 16 S rRNA sequencing. RESULTS: The phylogenetic diversity of microbial communities in both RA and non-RA controls was significantly higher in deep subgingival sites compared to shallow sites (p = 0.022), and the overall subgingival microbiome clustered primarily according to probing depth (i.e. shallow versus deep sites), and not separated by RA status. While a large number of differentially abundant taxa and gene functions was observed between deep and shallow sites as expected in non-RA controls, we found very few differentially abundant taxa and gene functions between deep and shallow sites in RA subjects. In addition, compared to non-RA controls, the UniFrac distances between deep and shallow sites in RA subjects were smaller, suggesting increased similarity between deep and shallow subgingival microbiome in RA. Streptococcus parasanguinis and Actinomyces meyeri were overabundant in RA subjects, while Gemella morbillorum, Kingella denitrificans, Prevotella melaninogenica and Leptotrichia spp. were more abundant in non-RA subjects. CONCLUSIONS: The aggregate subgingival microbiome was not significantly different between individuals with and without rheumatoid arthritis. Although the differences in the overall subgingival microbiome was driven primarily by probing depth, in contrast to the substantial microbiome differences typically seen between deep and shallow sites in non-RA patients, the microbiome of deep and shallow sites in RA patients were more similar to each other. These results suggest that factors associated with RA may modulate the ecology of subgingival microbiome and its relationship to periodontal disease, the basis of which remains unknown but warrants further investigation.


Assuntos
Artrite Reumatoide , Microbiota , Actinomycetaceae , Gemella , Humanos , Kingella , Filogenia , Projetos Piloto , Streptococcus
3.
Emerg Infect Dis ; 27(3): 703-709, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33622463

RESUMO

Kingella spp. have emerged as an important cause of invasive pediatric diseases. Data on Kingella infective endocarditis (KIE) in children are scarce. We compared the clinical features of pediatric KIE cases with those of Streptococcus species IE (StIE) and Staphylococcus aureus IE (SaIE). A total of 60 patients were included in the study. Throughout the study period, a rise in incidence of KIE was noted. KIE patients were significantly younger than those with StIE and SaIE, were predominately boys, and had higher temperature at admission, history of oral aphthae before IE diagnosis, and higher lymphocyte count (p<0.05). Pediatric KIE exhibits unique features compared with StIE and SaIE. Therefore, in young healthy children <36 months of age, especially boys, with or without a congenital heart defect, with a recent history of oral aphthae, and experiencing signs and symptoms compatible with endocarditis, Kingella should be suspected as the causative pathogen.


Assuntos
Endocardite Bacteriana , Endocardite , Infecções Estafilocócicas , Criança , Humanos , Israel , Kingella , Masculino
4.
Artigo em Inglês | MEDLINE | ID: mdl-33168608

RESUMO

Neisseria meningitidis and Neisseria gonorrhoeae, two highly related species that might have emerged from a common commensal ancestor, constitute major human threats. Vaccines are available to prevent N. meningitidis infection, whereas there are only a limited number of antibiotics available for N. gonorrhoeae Unfortunately, some strains of these species are rapidly evolving and capable of escaping human interventions. Thus, it is now urgent to develop new avenues to fight these bacteria. This study reports that a boron-based salt, sodium tetraphenylborate (NaBPh4), displays high bactericidal activity and remarkable specificity against N. meningitidis and N. gonorrhoeae Other closely related commensal species such as Neisseria lactamica, which is found in the normal flora of healthy individuals, were found to be less affected even at 5-fold higher doses of NaBPh4 This specificity was further observed when much lower sensitivity was found for more distant Neisseriaceae species (such as Neisseria elongata or Kingella oralis) and completely unrelated species. Significant boron uptake by N. meningitidis cells was observed after incubation with 5 µM NaBPh4, as measured by inductively coupled plasma mass spectrometry, suggesting that this drug candidate's target(s) could be located intracellularly or within the cell envelope. Furthermore, mutants with slightly decreased susceptibility displayed alterations in genes coding for cell envelope elements, which reduced their virulence in an animal model of infection. Finally, a single dose of NaBPh4 resulted in a significant reduction in bacterial burden in a mouse model of N. meningitidis bacteremia. Although numerous boron-containing species were previously reported for their complex biological activities, the observation of this narrow selectivity is unprecedented and of potential importance from a therapeutic standpoint.


Assuntos
Infecções Bacterianas , Neisseria meningitidis , Animais , Kingella , Neisseria gonorrhoeae , Neisseria meningitidis/genética , Tetrafenilborato
5.
PLoS One ; 15(10): e0241511, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33125432

RESUMO

Kingella negevensis is a newly described gram-negative bacterium in the Neisseriaceae family and is closely related to Kingella kingae, an important cause of pediatric osteoarticular infections and other invasive diseases. Like K. kingae, K. negevensis can be isolated from the oropharynx of young children, although at a much lower rate. Due to the potential for misidentification as K. kingae, the burden of disease due to K. negevensis is currently unknown. Similarly, there is little known about virulence factors present in K. negevensis and how they compare to virulence factors in K. kingae. Using a variety of approaches, we show that K. negevensis produces many of the same putative virulence factors that are present in K. kingae, including a polysaccharide capsule, a secreted exopolysaccharide, a Knh-like trimeric autotransporter, and type IV pili, suggesting that K. negevensis may have significant pathogenic potential.


Assuntos
Kingella kingae/patogenicidade , Kingella/patogenicidade , Infecções por Neisseriaceae/microbiologia , Fatores de Virulência/análise , Proteínas de Bactérias/análise , Fímbrias Bacterianas/química , Fímbrias Bacterianas/microbiologia , Humanos , Kingella/química , Kingella kingae/química , Polissacarídeos Bacterianos/análise , Virulência
6.
Am J Trop Med Hyg ; 103(2): 672-674, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32431277

RESUMO

We report a patient with risk factors for both microbial keratitis and endophthalmitis, which were initially challenging to distinguish. Cultures of corneal scrapings yielded several organisms, including an uncultivable Gram-negative rod, eventually identified as Kingella negevensis. Kingella negevensis is so named because most strains have been isolated in the Negev, a desert region of southern Israel. The epidemiology of K. negevensis remains incompletely understood. We found no other reports in the literature of this organism causing microbial keratitis.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/complicações , Cocaína/administração & dosagem , Inibidores da Captação de Dopamina/administração & dosagem , Endoftalmite/complicações , Ceratite/complicações , Infecções por Neisseriaceae/complicações , Infecções Estreptocócicas/complicações , Abuso de Substâncias por Via Intravenosa/complicações , Administração Oftálmica , Adulto , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Ceftazidima/uso terapêutico , Coinfecção/complicações , Coinfecção/diagnóstico , Coinfecção/tratamento farmacológico , Doxiciclina/uso terapêutico , Endoftalmite/diagnóstico , Endoftalmite/tratamento farmacológico , Endoftalmite/microbiologia , Feminino , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Ceratite/diagnóstico , Ceratite/tratamento farmacológico , Ceratite/microbiologia , Kingella/genética , Kingella/isolamento & purificação , Linezolida/uso terapêutico , Moxifloxacina/uso terapêutico , Infecções por Neisseriaceae/diagnóstico , Infecções por Neisseriaceae/tratamento farmacológico , Infecções por Neisseriaceae/microbiologia , Soluções Oftálmicas , Prednisona/uso terapêutico , Propionibacterium acnes/isolamento & purificação , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Streptococcus/isolamento & purificação , Tobramicina/uso terapêutico , Vancomicina/uso terapêutico , Voriconazol/uso terapêutico
7.
J Infect Chemother ; 26(5): 510-512, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31982291

RESUMO

Eikenella corrodens is a facultatively anaerobic gram-negative rod bacterium in the oropharynx and respiratory tract. It is a member of HACEK (Haemophilus spp., Aggregatibacter spp., Cardiobacterium hominis, E. corrodens, and Kingella kingae) group commonly associated with endocarditis and craniofacial infections. It is usually susceptible to penicillin, second and third-generation cephalosporins, and carbapenem, but has variable susceptibility to first-generation cephalosporin. We herein provide a description of the first case of pediatric acute dacryocystitis caused by E. corrodens. The patient did not respond to oral cephalexin and required surgical drainage followed by intravenous cefotaxime. Also provided is a brief review of the current literature.


Assuntos
Dacriocistite/diagnóstico , Dacriocistite/microbiologia , Eikenella corrodens/patogenicidade , Infecções por Bactérias Gram-Negativas/microbiologia , Doença Aguda , Aggregatibacter , Antibacterianos/administração & dosagem , Cardiobacterium , Cefotaxima/administração & dosagem , Cefalexina/administração & dosagem , Pré-Escolar , Dacriocistite/tratamento farmacológico , Vias de Administração de Medicamentos , Eikenella corrodens/isolamento & purificação , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Haemophilus , Humanos , Kingella , Testes de Sensibilidade Microbiana , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Int J Infect Dis ; 76: 120-125, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30153485

RESUMO

OBJECTIVES: The study aimed to describe the epidemiological, microbiological, and clinical features of a population sample of 17 patients with HACEK infective endocarditis (HACEK-IE) and to compare them with matched control patients with IE caused by viridans group streptococci (VGS-IE). METHODS: Cases of definite (n=14, 82.2%) and possible (n=3, 17.6%) HACEK-IE included in the Infective Endocarditis Hospital Clinic of Barcelona (IE-HCB) database between 1979 and 2016 were identified and described. Furthermore, a retrospective case-control analysis was performed, matching each case to three control subjects with VGS-IE registered in the same database during the same time period. RESULTS: Seventeen out of 1209 IE cases (1.3%, 95% confidence interval 0.69-1.91%) were due to HACEK group organisms. The most frequently isolated HACEK species were Aggregatibacter spp (n=11, 64.7%). Intracardiac vegetations were present in 70.6% of cases. Left heart failure (LHF) was present in 29.4% of cases. Ten patients (58.8%) required in-hospital surgery and none died during hospitalization. In the case-control analysis, there was a trend towards larger vegetations in the HACEK-IE group (median (interquartile range) size 11.5 (10.0-20.0) mm vs. 9.0 (7.0-13.0) mm; p=0.068). Clinical manifestations, echocardiographic findings, LHF rate, systemic emboli, and other complications were all comparable (p>0.05). In-hospital surgery and mortality were similar in the two groups. One-year mortality was lower for HACEK-IE (1/17 vs. to 6/48; p=0.006). CONCLUSIONS: HACEK-IE represented 1.3% of all IE cases. Clinical features and outcomes were comparable to those of the VGS-IE control group. Despite the trend towards a larger vegetation size, the embolic event rate was not higher and the 1-year mortality was significantly lower for HACEK-IE.


Assuntos
Endocardite Bacteriana/microbiologia , Adulto , Aggregatibacter/isolamento & purificação , Cardiobacterium/isolamento & purificação , Eikenella corrodens/isolamento & purificação , Endocardite Bacteriana/epidemiologia , Endocardite Bacteriana/mortalidade , Feminino , Haemophilus/isolamento & purificação , Humanos , Kingella/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
J Clin Microbiol ; 56(10)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30045866

RESUMO

The recognition of the role of Kingella kingae as one of the main etiologic agents of skeletal system infections in young children and the recent discovery of the novel Kingella negevensis species have resulted in an increasing interest in these two emerging pediatric pathogens. Both bacteria colonize the oropharynx and are not detected in nasopharyngeal specimens, and the colonized mucosal surface is their portal of entry to the bloodstream. Although species-specific nucleic acid amplification assays have significantly improved the detection of kingellae and facilitated patients' management, the increasing use of this diagnostic approach has the potential drawback of neglecting culture recovery of these organisms. The isolation of Kingella species enables the thorough genotyping of strains for epidemiological purposes, the study of the dynamics of asymptomatic colonization and person-to-person transmission, the investigation of the pathogenesis of invasive infections, and the determination of antibiotic susceptibility patterns. The culture isolation of pharyngeal strains and their comparison with isolates derived from normally sterile body sites may also aid in identifying virulence factors involved in the transition from colonization to invasive disease which could represent potential targets for a future protective vaccine. The two species are notoriously fastidious, and their isolation from upper respiratory tract specimens requires a short transport time, plating on selective vancomycin-containing blood-agar medium, and incubation under capnophilic and aerobic conditions. The identification of K. kingae and K. negevensis can be performed by a combination of the typical Gram stain and biochemical tests and confirmed and differentiated by molecular assays that target the groEL and mdh genes.


Assuntos
Kingella/isolamento & purificação , Infecções por Neisseriaceae/diagnóstico , Infecções por Neisseriaceae/microbiologia , Orofaringe/microbiologia , Criança , Meios de Cultura , Genótipo , Humanos , Kingella/classificação , Kingella/genética , Kingella/patogenicidade , Kingella kingae/classificação , Kingella kingae/genética , Kingella kingae/isolamento & purificação , Kingella kingae/patogenicidade , Fenótipo , Virulência
10.
Int J Infect Dis ; 68: 83-87, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29408674

RESUMO

OBJECTIVES: Bacteria with common microbiological and clinical characteristics are often recognized as a particular group. The acronym HACEK stands for five fastidious genera associated with infective endocarditis (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella). Data on the epidemiology of HACEK are sparse. This article reports a 6-year nationwide study of HACEK bacteraemia in Denmark. METHODS: Cases of HACEK bacteraemia occurring during the years 2010-2015 were retrieved from the national Danish microbiology database, covering an average surveillance population of 5.6 million per year. RESULTS: A total of 147 cases of HACEK bacteraemia were identified, corresponding to an annual incidence of 0.44 per 100000 population. The annual incidence for males was 0.56 per 100000 and for females was 0.31 per 100000. The median age was 56 years (range 0-97 years), with variation among the genera. One hundred and forty-three isolates were identified to the species level and six to the genus level: Haemophilus spp, n=55; Aggregatibacter spp, n=37; Cardiobacterium spp, n=9; Eikenella corrodens n=21; and Kingella spp, n=27. CONCLUSIONS: This is the first study on the incidence of HACEK bacteraemia in a large surveillance population and may inspire further studies on the HACEK group. Haemophilus spp other than Haemophilus influenzae accounted for most cases of HACEK bacteraemia in Denmark, with Aggregatibacter spp in second place.


Assuntos
Bacteriemia/epidemiologia , Endocardite Bacteriana/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aggregatibacter , Bacteriemia/diagnóstico , Cardiobacterium , Criança , Pré-Escolar , Dinamarca/epidemiologia , Eikenella corrodens , Endocardite Bacteriana/diagnóstico , Feminino , Haemophilus , Humanos , Incidência , Lactente , Kingella , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Adulto Jovem
11.
Pan Afr Med J ; 28: 83, 2017.
Artigo em Francês | MEDLINE | ID: mdl-29255553

RESUMO

Kingella denitrificans is a non-pathogenic micro-organism present in oropharyngeal flora. This germ has been recently recognized as responsible for opportunistic invasive infections mainly affecting immunosuppressed patients. We here report the case of a child aged 3 years and 7 months followed-up since the age of one year for bone marrow failure syndrome associated with pancytopenia of undetermined origin who had bacteremia due to Kingella denitrificans, a group of difficult to culture gram-negative bacteria rarely described in the literature. Clinicians and microbiologists should suspect the presence of this germ especially in immunosuppressed patients. The use of blood culture bottle contributes in a significant way to the detection of this germ.


Assuntos
Anemia Aplástica/imunologia , Bacteriemia/diagnóstico , Doenças da Medula Óssea/imunologia , Hemoglobinúria Paroxística/imunologia , Infecções por Neisseriaceae/diagnóstico , Infecções Oportunistas/diagnóstico , Bacteriemia/microbiologia , Transtornos da Insuficiência da Medula Óssea , Pré-Escolar , Humanos , Hospedeiro Imunocomprometido , Kingella/isolamento & purificação , Masculino , Infecções por Neisseriaceae/microbiologia , Infecções Oportunistas/microbiologia
12.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 35(supl.3): 29-43, oct. 2017. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-170748

RESUMO

Las bacterias del grupo HACEK (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella), Pasteurella y Capnocytophaga son las bacterias gramnegativas de crecimiento lento que con mayor frecuencia causan infecciones en el ser humano. Forman parte de la microbiota del tracto respiratorio superior y genitourinario del ser humano y de animales, y pueden causar infecciones en cualquier localización, pero fundamentalmente de piel y tejidos blandos, así como bacteriemia y endocarditis. Su clasificación taxonó- mica es compleja y está en constante revisión. Son bacterias nutricionalmente exigentes, y para el desarrollo de colonias visibles requieren agar sangre y agar chocolate, una atmósfera aerobia, generalmente enriquecida en CO2 y una incubación de 48 h. La identificación fenotípica de especie es complicada y no siempre es posible, ya que requiere múltiples sustratos que normalmente no están disponibles en los laboratorios de rutina, ni en los sistemas automatizados. La aplicación de las técnicas moleculares y proteómicas ha permitido una mejor identificación de estas bacterias. El tratamiento de estas infecciones se encuentra con el problema de que los datos de sensibilidad a los agentes antimicrobianos son limitados; no obstante, de los datos disponibles se conoce que amoxicilina-ácido clavulánico, cefalosporinas de segunda y tercera generaciones y fluoroquinolonas son generalmente activas frente a ellas (AU)


Bacteria from the HACEK group (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella), Pasteurella and Capnocytophaga are slow-growing gram-negative bacteria that most frequently cause infections in humans. They are part of the microbiota of the upper respiratory and genitourinary tracts of humans and animals, and can cause infections in any location, although mainly skin and soft tissue infections, as well as bacteraemia and endocarditis. Taxonomic classification is complex and under constant review. These are nutritionally demanding bacteria that require blood and chocolate agar, an aerobic atmosphere, generally CO2-enriched, and 48 h incubation for the development of visible colonies. Phenotypic identification at the species level is complicated and not always possible because it requires multiple substrates that are not normally available in routine laboratories or in automated systems. Application of molecular and proteomic techniques has enabled better identification of these bacteria. Treatment of related infections is hindered by a lack of data on susceptibility to antimicrobial agents. However, evidence suggests that amoxicillin-clavulanic acid, second- and third-generation cephalosporins and fluoroquinolones are generally active against these bacteria (AU)


Assuntos
Humanos , Bactérias Gram-Positivas/isolamento & purificação , Capnocytophaga/isolamento & purificação , Pasteurella/isolamento & purificação , Bacteriemia/microbiologia , Doenças por Vírus Lento/classificação , Doenças por Vírus Lento/microbiologia , Doenças por Vírus Lento/epidemiologia , Microbiota , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Cefalosporinas/uso terapêutico , Infecções por Haemophilus/microbiologia , Haemophilus/isolamento & purificação , Aggregatibacter/isolamento & purificação , Cardiobacterium/isolamento & purificação , Eikenella/isolamento & purificação , Kingella/isolamento & purificação
13.
Microbes Infect ; 19(11): 546-552, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28802585

RESUMO

Kingella kingae, producing the cytotoxic RTX protein, is a causative agent of serious infections in humans such as bacteremia, endocarditis and osteoarticular infection, especially in young children. Recently, Kingella negevensis, a related species, has been isolated from the oral cavity of healthy children. In this study, we report the isolation of K. negevensis strain eburonensis, initially misidentified as K. kingae with MALDI-TOF MS, from a vaginal specimen of a patient suffering of vaginosis. The genome sequencing and analysis of this strain together with comparative genomics of the Kingella genus revealed that K. negevensis possesses a full homolog of the rtx operon of K. kingae involved in the synthesis of the RTX toxin. We report that a K. kingae specific diagnostic PCR, based on the rtxA gene, was positive when tested on K. negevensis strain eburonensis DNA. This cross-amplification, and risk of misidentification, was confirmed by in silico analysis of the target gene sequence. To overcome this major diagnostic issue we developed a duplex real-time PCR to detect and distinguish K. kingae and K. negevensis. In addition to this, the identification of K. negevensis raises a clinical issue in term of pathogenic potential given the production of a RTX hemolysin.


Assuntos
Toxinas Bacterianas/genética , Kingella/genética , Infecções por Neisseriaceae/diagnóstico , Feminino , Genômica , Humanos , Kingella/isolamento & purificação , Infecções por Neisseriaceae/genética , Infecções por Neisseriaceae/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real , Vaginose Bacteriana/microbiologia , Adulto Jovem
14.
Int J Syst Evol Microbiol ; 67(7): 2370-2376, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28699877

RESUMO

We herein report the isolation and characterization of 21 Gram-stain-negative strains cultivated from the oropharynx of healthy children in Israel and Switzerland. Initially described as small colony variants of Kingella kingae, phenotypic analysis, biochemical analysis, phylogenetic analysis based on sequencing of the partial 16S rRNA gene and five housekeeping genes (abcZ, adk, G6PD, groEL and recA), and whole genome sequencing and comparison between members of the genera Kingella and Neisseria provided evidence for assigning them to the genus Kingella. Cellular fatty acids included important amounts of C12 : 0, C14 : 0, C16 : 0 and C16 : 1n7. Digital DNA-DNA hybridization between the isolates Sch538T and K. kingae ATCC 23330T revealed relatedness of 19.9 %. Comparative analysis of 16S rRNA gene sequences available in GenBank allowed matches to strains isolated in the USA, suggesting a wider geographical distribution. A novel species named Kingella negevensis sp. nov. is proposed, as most strains have been isolated in the Negev, a desert region of southern Israel. The type strain is Sch538T (=CCUG 69806T=CSUR P957).


Assuntos
Kingella/classificação , Orofaringe/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Criança , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Humanos , Israel , Kingella/genética , Kingella/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Suíça
15.
Expert Rev Anti Infect Ther ; 14(6): 539-45, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27124204

RESUMO

INTRODUCTION: The HACEK group, referring to Haemophilus spp., Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae, is a rare cause of infective endocarditis (IE). It causes the majority of Gram-negative endocarditis cases and has an excellent prognosis and simple management if properly identified. However, delay in diagnosis and associated complications can render the infection fatal. AREAS COVERED: Over the past few decades, there have been tremendous advancements in understanding the manifestations and progression of HACEK endocarditis (HE). This review tackles the epidemiology of HE, the microbiological characteristics of each organism in the HACEK group, the methods used to diagnose HE, the clinical manifestations, complications, and mortality of patients with HE, as well as the recommended treatment and preventive methods. Expert Commentary: The lack of robust randomized controlled trials in diagnosis and treatment of HE makes it difficult to determine the optimal management of such infections. Nevertheless, advancements in culturing methods have shown progress in isolating and identifying these fastidious organisms. Positive blood cultures for any of the HACEK organisms in the setting of no definite focus of infection is highly suggestive of HE. In such cases, treatment with ceftriaxone or a fluoroquinolone, even without obtaining antibiotic susceptibilities, should be initiated. Moreover, the decision to proceed with surgical intervention should be individualized. As is the case for other IE, HE requires the collaboration of a multidisciplinary team consisting of the infectious disease specialist, cardiologist, cardiothoracic surgeon, and the microbiologist.


Assuntos
Endocardite Bacteriana/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Aggregatibacter/efeitos dos fármacos , Aggregatibacter/isolamento & purificação , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Cardiobacterium/efeitos dos fármacos , Cardiobacterium/isolamento & purificação , Ecocardiografia , Eikenella corrodens/efeitos dos fármacos , Eikenella corrodens/isolamento & purificação , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/epidemiologia , Bactérias Gram-Negativas/isolamento & purificação , Haemophilus/efeitos dos fármacos , Haemophilus/isolamento & purificação , Humanos , Kingella/efeitos dos fármacos , Kingella/isolamento & purificação , Testes de Sensibilidade Microbiana
16.
Nat Commun ; 6: 10172, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26671256

RESUMO

The Neisseriaceae family of bacteria causes a range of diseases including meningitis, septicaemia, gonorrhoea and endocarditis, and extracts haem from haemoglobin as an important iron source within the iron-limited environment of its human host. Herein we report crystal structures of apo- and haemoglobin-bound HpuA, an essential component of this haem import system. The interface involves long loops on the bacterial receptor that present hydrophobic side chains for packing against the surface of haemoglobin. Interestingly, our structural and biochemical analyses of Kingella denitrificans and Neisseria gonorrhoeae HpuA mutants, although validating the interactions observed in the crystal structure, show how Neisseriaceae have the fascinating ability to diversify functional sequences and yet retain the haemoglobin binding function. Our results present the first description of HpuA's role in direct binding of haemoglobin.


Assuntos
Proteínas de Bactérias/metabolismo , Hemoglobinas/metabolismo , Kingella/metabolismo , Neisseria gonorrhoeae/metabolismo , Receptores de Superfície Celular/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Cristalização , Humanos , Kingella/genética , Neisseria gonorrhoeae/genética , Neisseriaceae/genética , Neisseriaceae/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Receptores de Superfície Celular/química , Receptores de Superfície Celular/genética
19.
J Infect Chemother ; 20(3): 169-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24462438

RESUMO

In the stomach of a gastric ulcer patient who had been administered an anti-acid, a gram-negative and urease-negative bacillus similar in size to Helicobacter pylori was infected together with H. pylori. According to biochemical test and 16S rRNA gene analysis, the urease-negative bacterium was identified as Kingella denitrificans, a human nasopharyngeal commensal. In contrast to the standard strain of K. denitrificans, the isolate showed catalase activity, did not produce acid from glucose, and exhibited acid tolerance. Acid tolerance of H. pylori was increased by cocultivation with the K. denitrificans isolate, but not with other isolates of K. denitrificans. Disruption of physiological and immunological niche by dysbiotic colonization of bacterium may provide pathological attributes to human stomach. Collectively, a careful administration of anti-acids to the elderly, especially those with atrophic gastritis, is necessary to avoid repression of the gastric barrier to bacteria.


Assuntos
Portador Sadio/microbiologia , Kingella/isolamento & purificação , Infecções por Neisseriaceae/microbiologia , Úlcera Gástrica/microbiologia , Idoso , Antiulcerosos/efeitos adversos , Antiulcerosos/uso terapêutico , Biópsia , Portador Sadio/diagnóstico , Mucosa Gástrica/citologia , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Helicobacter pylori , Humanos , Concentração de Íons de Hidrogênio , Kingella/fisiologia , Masculino , Viabilidade Microbiana , Infecções por Neisseriaceae/diagnóstico , Ranitidina/efeitos adversos , Ranitidina/uso terapêutico , Úlcera Gástrica/tratamento farmacológico
20.
PLoS One ; 8(5): e63181, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23690995

RESUMO

The HACEK organisms (Haemophilus species, Aggregatibacter species, Cardiobacterium hominis, Eikenella corrodens, and Kingella species) are rare causes of infective endocarditis (IE). The objective of this study is to describe the clinical characteristics and outcomes of patients with HACEK endocarditis (HE) in a large multi-national cohort. Patients hospitalized with definite or possible infective endocarditis by the International Collaboration on Endocarditis Prospective Cohort Study in 64 hospitals from 28 countries were included and characteristics of HE patients compared with IE due to other pathogens. Of 5591 patients enrolled, 77 (1.4%) had HE. HE was associated with a younger age (47 vs. 61 years; p<0.001), a higher prevalence of immunologic/vascular manifestations (32% vs. 20%; p<0.008) and stroke (25% vs. 17% p = 0.05) but a lower prevalence of congestive heart failure (15% vs. 30%; p = 0.004), death in-hospital (4% vs. 18%; p = 0.001) or after 1 year follow-up (6% vs. 20%; p = 0.01) than IE due to other pathogens (n = 5514). On multivariable analysis, stroke was associated with mitral valve vegetations (OR 3.60; CI 1.34-9.65; p<0.01) and younger age (OR 0.62; CI 0.49-0.90; p<0.01). The overall outcome of HE was excellent with the in-hospital mortality (4%) significantly better than for non-HE (18%; p<0.001). Prosthetic valve endocarditis was more common in HE (35%) than non-HE (24%). The outcome of prosthetic valve and native valve HE was excellent whether treated medically or with surgery. Current treatment is very successful for the management of both native valve prosthetic valve HE but further studies are needed to determine why HE has a predilection for younger people and to cause stroke. The small number of patients and observational design limit inferences on treatment strategies. Self selection of study sites limits epidemiological inferences.


Assuntos
Endocardite Bacteriana/epidemiologia , Endocardite Bacteriana/fisiopatologia , Endocardite Bacteriana/terapia , Fatores Etários , Aggregatibacter , Cardiobacterium , Estudos de Coortes , Eikenella corrodens , Endocardite Bacteriana/microbiologia , Haemophilus , Humanos , Kingella , Razão de Chances , Prevalência , Estatísticas não Paramétricas , Resultado do Tratamento
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