Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Sci Rep ; 9(1): 4481, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30872664

RESUMEN

The human commensal Haemophilus parainfluenzae is emerging as an opportunistic multidrug-resistant pathogen. The objectives of this work were to characterise a new capsular operon of extensively drug-resistant (XDR) H. parainfluenzae clinical isolates and study their resistance mechanisms using whole-genome sequencing. All strains were resistant to: ß-lactams, via amino acid changes in PBP3 (S385T, I442F, V511A, N526K and V562I); quinolones, by alterations in GyrA (S84F and D88Y) and ParC (S84F and S138T); chloramphenicol, through the presence of catS; macrolides, via the presence of mel and mef(E)-carrying MEGA element; and tetracycline, through the presence of tet(M) and/or tet(B). Phylogenetic analysis revealed high genomic diversity when compared to the H. parainfluenzae genomes available on the NCBI, the isolates from this study being closely related to the Swiss XDR AE-2096513. A full capsular operon showing homology to that of H. influenzae was identified, in accordance with the observation of a capsular structure by TEM. This study describes for the first time a capsular operon in H. parainfluenzae, a major determinant of pathogenicity that may contribute to increased virulence in XDR clinical isolates. Moreover, phylogenetic analysis suggests the possible spread of an XDR-encapsulated strain in Europe.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Infecciones por Haemophilus/microbiología , Haemophilus parainfluenzae/clasificación , Polisacáridos Bacterianos/genética , Secuenciación Completa del Genoma/métodos , Adulto , Cloranfenicol/farmacología , Femenino , Haemophilus parainfluenzae/genética , Haemophilus parainfluenzae/aislamiento & purificación , Humanos , Macrólidos/farmacología , Masculino , Pruebas de Sensibilidad Microbiana , Operón , Filogenia , Quinolonas/farmacología , Tetraciclina/farmacología , beta-Lactamas/farmacología
2.
Infect Genet Evol ; 44: 507-509, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27497656

RESUMEN

We report an H. parainfluenzae clinical isolate resistant to cefotaxime and with decreased susceptibility to ciprofloxacin recovered from a patient with cystic fibrosis. The isolate had elevated MICs of ampicillin (256mg/L), amoxicillin-clavulanate (8mg/L), cefuroxime (8mg/L) and cefotaxime (4mg/L), and showed a ß-lactamase-producing amoxicillin-clavulanic acid-resistant (BLPACR) phenotype. A blaTEM-1 plus five amino acid substitutions in the PBP3 were found: Ser385Thr, Val511Ala, Ile519Val, Asn526Lys and Asp551Leu. MIC of ciprofloxacin was 0.5mg/L, and substitutions in gyrA (Ser84Tyr) and parC (Ser84Phe) genes were detected.


Asunto(s)
Antibacterianos/farmacología , Cefotaxima/farmacología , Farmacorresistencia Bacteriana , Fluoroquinolonas/farmacología , Infecciones por Haemophilus/microbiología , Haemophilus parainfluenzae/efectos de los fármacos , Haemophilus parainfluenzae/genética , Sustitución de Aminoácidos , Genes Bacterianos , Haemophilus parainfluenzae/clasificación , Haemophilus parainfluenzae/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana
3.
J Med Microbiol ; 63(Pt 6): 805-811, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24648471

RESUMEN

The identification of Haemophilus spp. from urogenital sites can be challenging due to the lack of appropriate media for culturing the organisms and the poor resolution of biochemical methods. By incorporating chocolate agar and 16S rRNA gene sequence analysis in our protocol to identify Haemophilus spp. from urinary specimens, we isolated and characterized 30 genetically homogeneous strains of a cryptic species that is phylogenetically close to, but distinct from, Haemophilus parainfluenzae. Commercial biochemical kits and VITEK 2 could not distinguish between the two species. Over 90 % of the strains were isolated from urine and the urogenital area, made possible with the inclusion of chocolate agar in our urine culture protocol. In contrast, no Haemophilus strains isolated from respiratory specimens were identified as the cryptic genospecies. The cryptic genospecies was associated with urinary tract infections (UTIs) in certain patient populations. Distinct from Haemophilus quentinii that also causes urogenital infection, the cryptic genospecies required V factor (NAD) but not X factor (haemin) to grow. The data indicated that 16S rRNA gene sequencing may be necessary in identifying Haemophilus species and that inaccurate categorization of Haemophilus strains isolated from urogenital specimens based on phenotypic characteristics may prevent accurate diagnosis of UTIs.


Asunto(s)
Haemophilus parainfluenzae/clasificación , Infecciones Oportunistas/microbiología , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Infecciones Urinarias/microbiología , Regulación Bacteriana de la Expresión Génica , Especiación Genética , Haemophilus parainfluenzae/genética , Haemophilus parainfluenzae/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Infecciones Oportunistas/epidemiología , Filogenia , Infecciones Urinarias/epidemiología
4.
Antimicrob Agents Chemother ; 57(6): 2867-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23545526

RESUMEN

Two homosexual men were colonized in the urethra with Haemophilus parainfluenzae nonsusceptible to ampicillin (MIC, 8 µg/ml), amoxicillin-clavulanate (MIC, 4 µg/ml), cefotaxime (MIC, 1.5 µg/ml), cefepime (MIC, 3 µg/ml), meropenem (MIC, 0.5 µg/ml), cefuroxime, azithromycin, ciprofloxacin, tetracycline, and chloramphenicol (all MICs, ≥ 32 µg/ml). Repetitive extragenic palindromic PCR (rep-PCR) showed that the strains were indistinguishable. The isolates had amino acid substitutions in PBP3, L4, GyrA, and ParC and possessed Mef(A), Tet(M), and CatS resistance mechanisms. This is the first report of extensively drug-resistant (XDR) H. parainfluenzae.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Haemophilus/microbiología , Haemophilus parainfluenzae/efectos de los fármacos , Uretritis/microbiología , Sustitución de Aminoácidos , Antibacterianos/clasificación , Proteínas Bacterianas/genética , Infecciones por Haemophilus/tratamiento farmacológico , Haemophilus parainfluenzae/clasificación , Haemophilus parainfluenzae/genética , Haemophilus parainfluenzae/aislamiento & purificación , Homosexualidad Masculina , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Análisis de Secuencia de ADN , Suiza , Uretra/microbiología , Uretritis/tratamiento farmacológico
5.
J Med Microbiol ; 62(Pt 5): 792-793, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23412773

RESUMEN

Urinary tract infections (UTIs) caused by Haemophilus parainfluenzae represent a very small percentage of this kind of pathology in children, and it has scarcely been described in the medical literature. According to previous studies of over 800 urine samples in children under 15 years old, a decrease of 50% (from 0.13% to 0.07%) is estimated in its occurrence over the last two decades. This can be explained by the early detection of UTIs and their early empirical treatment, because this micro-organism shows high sensitivity to antibiotics. Also, the culture media in which this bacterium grows are not included in most current protocols. Here we report a case of a UTI caused by H. parainfluenzae in a 4-year-old boy.


Asunto(s)
Combinación Amoxicilina-Clavulanato de Potasio/uso terapéutico , Antibacterianos/uso terapéutico , Infecciones por Haemophilus/microbiología , Haemophilus parainfluenzae/aislamiento & purificación , Infecciones Urinarias/microbiología , Preescolar , Haemophilus parainfluenzae/clasificación , Humanos , Masculino , Infecciones Urinarias/complicaciones
6.
Biomed Environ Sci ; 25(3): 367-71, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22840589

RESUMEN

OBJECTIVE: To establish multiplex PCR-based assays for detecting H.influenzae and H.parainfluenzae. And the PCR-based assays were applied to detect the carriage rates of H.influenzae and H.parainfluenzae in nasopharyngeal swab specimens which were collected from healthy children. METHODS: Multiplex primers for species-specific PCR were designed by using DNAstar soft based on the sequences of 16S rRNA genes from genus Haemophilus to detect H.influenzae and H.parainfluenzae. RESULTS: The sensitivity of the 16S rRNA PCR assay for detecting H.influenzae and H.parainfluenzae was 97.53% and 100% respectively, and the specificity was 95.89% and 96.63% respectively. Youden's Index on the ability to detect H.influenzae and H.parainfluenzae was 0.9342 and 0.9663 respectively. 666 nasopharyngeal swab specimens were collected from healthy children. The detection rates of H.influenzae and H.parainfluenzae were 14.11% and 16.07% respectively by using isolation and culture methods. The detection rates of H.influenzae and H.parainfluenzae were 43.54% and 57.96% respectively by 16S rRNA PCR assays. The carriage rates of serotypes a, b, c, d, e, f and non-typeable isolates were 0% (0/666), 0.15% (1/666), 1.20% (8/666), 0.15% (1/666), 1.20% (8/666), 1.80% (12/666), 95.50% (636/666) respectively. CONCLUSION: The multiplex PCR assays were very rapid, reliable and feasible methods for detection of H.influenzae and H.parainfluenzae in pharyngeal swab specimens which were compared to conventional isolation and culture methods. 95.5% of H.influenzae strains in healthy children were nontypeable. The encapsulated or typable strains were mainly three serotypes which was c, e, and f serotype.


Asunto(s)
Haemophilus influenzae/aislamiento & purificación , Haemophilus parainfluenzae/aislamiento & purificación , Reacción en Cadena de la Polimerasa Multiplex/métodos , Nasofaringe/microbiología , Haemophilus influenzae/clasificación , Haemophilus influenzae/genética , Haemophilus parainfluenzae/clasificación , Haemophilus parainfluenzae/genética , Humanos , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Sensibilidad y Especificidad
7.
J Clin Microbiol ; 45(12): 4051-3, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17942653

RESUMEN

The biotypes of Haemophilus influenzae and Haemophilus parainfluenzae isolates were determined with three commercially available biochemical test kits: the IDS RapID NH system, the Neisseria-Haemophilus identification test (NHI card), and the API NH strip. The API NH strip performed best, correctly classifying the biotypes of 371 of 380 (97.6%) different challenge strains.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Haemophilus influenzae/clasificación , Haemophilus influenzae/aislamiento & purificación , Haemophilus parainfluenzae/clasificación , Haemophilus parainfluenzae/aislamiento & purificación , Infecciones por Haemophilus/diagnóstico , Haemophilus influenzae/metabolismo , Haemophilus parainfluenzae/metabolismo , Humanos , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad
8.
J Med Microbiol ; 56(Pt 6): 838-846, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17510272

RESUMEN

The objective of this study was to investigate the sequence diversity in a single country of a family of integrative and conjugative elements (ICEs) that are vectors of antibiotic resistance in Haemophilus influenzae and Haemophilus parainfluenzae, and test the hypothesis that they emerged from a single lineage. Sixty subjects aged 9 months - 13 years were recruited and oropharyngeal samples cultured. Up to 10 morphologically distinct Pasteurellaceae spp. were purified, and then the species were determined and differentiated by partial sequence analysis of 16S rDNA and mdh, respectively. ICEs were detected by PCR directed at five genes distributed evenly across the ICE. These amplicons were sequenced and aligned by the neighbour-joining algorithm. A total of 339 distinguishable isolates were cultured. ICEs with all 5 genes present were found in 9 of 110 (8 %) H. influenzae and 21 of 211 (10 %) H. parainfluenzae, respectively. ICEs were not detected among the other Pasteurellaceae. A total of 20 of 60 (33 %) children carried at least 1 oropharyngeal isolate with an ICE possessing all 5 genes. One of the five genes, integrase, however, consisted of two lineages, one of which was highly associated with H. influenzae. The topology of neighbour-joining trees of the remaining four ICE genes was compared and showed a lack of congruence; though, the genes form a common pool among H. influenzae and H. parainfluenzae. This family of antibiotic resistance ICEs was prevalent among the children studied, was genetically diverse, formed a large gene pool, transferred between H. influenzae and H. parainfluenzae, lacked population structure and possessed features suggestive of panmixia, all indicating it has not recently emerged from a single source.


Asunto(s)
Resistencia a Medicamentos/genética , Variación Genética , Haemophilus influenzae/efectos de los fármacos , Haemophilus influenzae/genética , Haemophilus parainfluenzae/efectos de los fármacos , Haemophilus parainfluenzae/genética , Secuencias Repetitivas Esparcidas/genética , Adolescente , Niño , Preescolar , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Grecia , Infecciones por Haemophilus/microbiología , Haemophilus influenzae/clasificación , Haemophilus influenzae/aislamiento & purificación , Haemophilus parainfluenzae/clasificación , Haemophilus parainfluenzae/aislamiento & purificación , Humanos , Lactante , Integrasas/genética , Malato Deshidrogenasa/genética , Orofaringe/microbiología , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Homología de Secuencia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...