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2.
Epidemiol Infect ; 146(11): 1461-1467, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29880080

RESUMEN

Foodborne non-typhoidal salmonellosis causes approximately 1 million illnesses annually in the USA. In April 2015, we investigated a multistate outbreak of 65 Salmonella Paratyphi B variant L(+) tartrate(+) infections associated with frozen raw tuna imported from Indonesia, which was consumed raw in sushi. Forty-six (92%) of 50 case-patients interviewed ate sushi during the week before illness onset, and 44 (98%) of 45 who specified ate sushi containing raw tuna. Two outbreak strains were isolated from the samples of frozen raw tuna. Traceback identified a single importer as a common source of tuna consumed by case-patients; this importer issued three voluntary recalls of tuna sourced from one Indonesian processor. Four Salmonella Weltevreden infections were also linked to this outbreak. Whole-genome sequencing was useful in establishing a link between Salmonella isolated from ill people and tuna. This outbreak highlights the continuing foodborne illness risk associated with raw seafood consumption, the importance of processing seafood in a manner that minimises contamination with pathogenic microorganisms and the continuing need to ensure imported foods are safe to eat. People at higher risk for foodborne illness should not consume undercooked animal products, such as raw seafood.


Asunto(s)
Brotes de Enfermedades , Microbiología de Alimentos , Fiebre Paratifoidea/etiología , Alimentos Crudos/microbiología , Salmonella paratyphi B/aislamiento & purificación , Atún/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , Electroforesis en Gel de Campo Pulsado , Femenino , Alimentos Congelados/efectos adversos , Alimentos Congelados/microbiología , Humanos , Indonesia , Lactante , Masculino , Persona de Mediana Edad , Fiebre Paratifoidea/epidemiología , Alimentos Crudos/efectos adversos , Salmonella paratyphi B/clasificación , Alimentos Marinos/efectos adversos , Alimentos Marinos/microbiología , Serotipificación , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Secuenciación Completa del Genoma , Adulto Joven
3.
Acta Medica (Hradec Kralove) ; 61(4): 125-130, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30664444

RESUMEN

INTRODUCTION: Enteric-fever is a major public-health problem in developing countries emerging as multidrug-resistant, Nalidixic-acid resistant and extremely drug-resistant Salmonella (Pakistan, 2016), has intensified the use of WHO watch/reserve group antimicrobials such as azithromycin and meropenem. METHODS: This ambispective-study was conducted on 782 non-repeat blood-culture isolates of S. Typhi, S. Paratyphi A and S. Paratyphi B obtained from 29,184 blood cultures received at a 1000-bedded tertiary-care hospital of North-India from 2011-2017. Identification and antibiograms were obtained by Vitek-2 compact and Kirby-Bauer's disc diffusion with resistance to ampicillin, chloramphenicol and cotrimoxazole being labeled as multidrug-resistant. Decreased ciprofloxacin-susceptibility and ciprofloxacin-resistance were defined as MIC 0.125-0.5 and >1 µg/ml. RESULTS: S. Typhi and S. Paratyphi A in a ratio of 3.9:1 were seen between July-September predominantly distributed between 6-45 year age group. Resistance to co-trimoxazole, chloramphenicol, ceftriaxone and azithromycin was 6.1%, 13.8%, 16.1 and 5.78% respectively. Multidrug-resistant S. typhi and S. paratyphi A were 2.73% and 1.91% respectively. CONCLUSION: Enteric-fever is a major public-health problem in India. Emergence of multidrug-resistant, Nalidixic-acid resistant and extremely-drug resistant Salmonella mandates ongoing surveillance for targeted empirical therapy and containment of spread. Repeated epidemics call for water, sanitation, hygiene and vaccination strategies to sustain herd-immunity.


Asunto(s)
Antibacterianos/uso terapéutico , Fiebre Tifoidea/tratamiento farmacológico , Fiebre Tifoidea/epidemiología , Adolescente , Adulto , Niño , Preescolar , Pruebas Antimicrobianas de Difusión por Disco , Farmacorresistencia Bacteriana , Femenino , Humanos , India/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Salmonella paratyphi A/aislamiento & purificación , Salmonella paratyphi B/aislamiento & purificación , Salmonella typhi/aislamiento & purificación , Centros de Atención Terciaria , Fiebre Tifoidea/microbiología
4.
Artículo en Inglés | MEDLINE | ID: mdl-28117713

RESUMEN

The infection dynamics of S. Java were examined in three consecutive rearing periods on a broiler farm in Northwestern Germany which had been persistently infected with S. Java for more than five years. The barn was investigated for Salmonella occurrence after cleaning and disinfection to verify the persistent contamination of the broiler house with S. Java before the start of the first rearing cycle. Confirmation of Salmonella absence in day-old chicks (time-point 1) as well as early establishment of infection between days 5-7 (time-point 2) were confirmed by caecal swabs prepared for qPCR and classical microbiological methods. At three time-periods (between days 11-15 (time-point 3), days 25-28 (time-point 4), and days 38-40 (time-point 5)) caecal content was examined for colony forming units (CFU) Salmonella/g. In general, there was an increase in Salmonella Java load at time-point 4 compared to time-points 3 and 5. Therefore, we observed a bell-shaped course of infection resulting in higher rates of Salmonella CFU/g prior to prethinning than at final slaughter. The antimicrobial susceptibility testing revealed resistance to tetracycline, fluorquinolones, trimethoprim, and cefoxitin.


Asunto(s)
Antibacterianos/farmacología , Pollos/microbiología , Farmacorresistencia Bacteriana , Salmonelosis Animal/tratamiento farmacológico , Salmonella paratyphi B/efectos de los fármacos , Crianza de Animales Domésticos , Animales , Alemania , Humanos , Indonesia , Salmonella paratyphi B/aislamiento & purificación
5.
J Med Microbiol ; 65(12): 1536-1539, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27902389

RESUMEN

Decreased ciprofloxacin susceptibility (DCS) and multidrug resistance in typhoidal Salmonella isolates in areas of endemicity are significant therapeutic problems. Guidelines for azithromycin disc diffusion and MIC interpretive criteria for Salmonella enterica serovar Typhi were published recently by the Clinical and Laboratory Standards Institute in 2015. We investigated the antimicrobial susceptibility pattern of azithromycin in 100 isolates of Salmonella Typhi (n=80), Paratyphi A (n=18) and B (n=2) recovered from bloodstream infections from January 2013 to December 2015. Zone sizes were extrapolated against MIC values, and a scatter plot was constructed. The azithromycin MICs by Etest ranged from 2 to 16 µg ml-1, while the disc diffusion diameters were from 13 to 22 mm. We observed that the margin of the zone of inhibition around the azithromycin disc may not be very clear and therefore difficult to interpret and that there was wide variation in the zone sizes for the same MIC value in both serovars. DCS was observed in 85 % of Salmonella Typhi recovered (68/80) and in 15/18 (83.3 %) Paratyphi A isolates. Judicious use of azithromycin is advocated as an alternative oral agent in endemic areas where DCS is common.


Asunto(s)
Antibacterianos/farmacología , Azitromicina/farmacología , Farmacorresistencia Bacteriana , Salmonella paratyphi A/efectos de los fármacos , Salmonella paratyphi B/efectos de los fármacos , Salmonella typhi/efectos de los fármacos , Bacteriemia/microbiología , Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , India/epidemiología , Pruebas de Sensibilidad Microbiana , Salmonella paratyphi A/aislamiento & purificación , Salmonella paratyphi B/aislamiento & purificación , Salmonella typhi/aislamiento & purificación , Serogrupo , Fiebre Tifoidea/epidemiología , Fiebre Tifoidea/microbiología
6.
Trans R Soc Trop Med Hyg ; 110(8): 472-9, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27618918

RESUMEN

BACKGROUND: We describe the antimicrobial susceptibility pattern of 100 typhoidal Salmonella isolates recovered from blood cultures and also investigate the association of decreased ciprofloxacin susceptibility with mutations in the genes coding for DNA gyrase and topoisomerase IV in 55 isolates. METHODS: The study was conducted between January 2013 and December 2015 at a tertiary care centre in north India. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion and E-test. Genotypic characterization included the screening of mutations in the quinolone resistance-determining region of gyrA, gyrB, parC, and parE by PCR. DNA sequence analysis was done for 55 isolates. RESULTS: Out of 100 isolates recovered 80 were S. Typhi, 18 were Paratyphi A and two were Paratyphi B. Eighty two percent (66/80) of S. Typhi and 15/18 S. Paratyphi A showed decreased ciprofloxacin susceptibility. The most common mutation in gyrA led to a change at codon 83 of serine to phenylalanine (n=37) or tyrosine (n=12). Five S. Typhi isolates that were resistant to ciprofloxacin (MICs of 12, 16, 24 and 32 µg/ml) had a second mutation at codon 87 in the gyrA gene changing aspartate to asparagine. CONCLUSIONS: There is a need to urgently review the use of fluoroquinolones for the management of enteric fever in endemic areas.


Asunto(s)
Ciprofloxacina/farmacología , Girasa de ADN/genética , Topoisomerasa de ADN IV/genética , Farmacorresistencia Bacteriana/genética , Salmonella paratyphi A/genética , Salmonella typhi/genética , Fiebre Tifoidea/microbiología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Pruebas Antimicrobianas de Difusión por Disco , Fluoroquinolonas , Genotipo , Humanos , India , Pruebas de Sensibilidad Microbiana , Mutación , Reacción en Cadena de la Polimerasa , Salmonella enterica/efectos de los fármacos , Salmonella enterica/genética , Salmonella enterica/aislamiento & purificación , Salmonella paratyphi A/efectos de los fármacos , Salmonella paratyphi A/aislamiento & purificación , Salmonella paratyphi B/efectos de los fármacos , Salmonella paratyphi B/genética , Salmonella paratyphi B/aislamiento & purificación , Salmonella typhi/efectos de los fármacos , Salmonella typhi/aislamiento & purificación , Análisis de Secuencia de ADN , Serogrupo , Centros de Atención Terciaria , Fiebre Tifoidea/tratamiento farmacológico
7.
mBio ; 7(4)2016 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-27555304

RESUMEN

UNLABELLED: For 100 years, it has been obvious that Salmonella enterica strains sharing the serotype with the formula 1,4,[5],12:b:1,2-now known as Paratyphi B-can cause diseases ranging from serious systemic infections to self-limiting gastroenteritis. Despite considerable predicted diversity between strains carrying the common Paratyphi B serotype, there remain few methods that subdivide the group into groups that are congruent with their disease phenotypes. Paratyphi B therefore represents one of the canonical examples in Salmonella where serotyping combined with classical microbiological tests fails to provide clinically informative information. Here, we use genomics to provide the first high-resolution view of this serotype, placing it into a wider genomic context of the Salmonella enterica species. These analyses reveal why it has been impossible to subdivide this serotype based upon phenotypic and limited molecular approaches. By examining the genomic data in detail, we are able to identify common features that correlate with strains of clinical importance. The results presented here provide new diagnostic targets, as well as posing important new questions about the basis for the invasive disease phenotype observed in a subset of strains. IMPORTANCE: Salmonella enterica strains carrying the serotype Paratyphi B have long been known to possess Jekyll and Hyde characteristics; some cause gastroenteritis, while others cause serious invasive disease. Understanding what makes up the population of strains carrying this serotype, as well as the source of their invasive disease, is a 100-year-old puzzle that we address here using genomics. Our analysis provides the first high-resolution view of this serotype, placing strains carrying serotype Paratyphi B into the wider genomic context of the Salmonella enterica species. This work reveals a history of disease dating back to the middle ages, caused by a group of distinct lineages with various abilities to cause invasive disease. By quantifying the key genomic differences between the invasive and noninvasive populations, we are able to identify key virulence-related targets that can form the basis of simple, rapid, point-of-care tests.


Asunto(s)
Genoma Bacteriano , Genotipo , Salmonella paratyphi B/clasificación , Salmonella paratyphi B/genética , Análisis de Secuencia de ADN , Animales , Análisis por Conglomerados , Humanos , Fiebre Paratifoidea/microbiología , Fiebre Paratifoidea/veterinaria , Salmonella paratyphi B/aislamiento & purificación
8.
Am J Trop Med Hyg ; 95(1): 19-25, 2016 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-27162265

RESUMEN

Owing to the increase in Salmonella strains with decreased fluoroquinolone susceptibility in the endemic areas, we have been treating enteric fever with intravenous ceftriaxone empirically since 2007. In this study, we reevaluated our treatment protocol. This retrospective cohort study was conducted at a single institute in Tokyo, Japan, between January 2006 and December 2013. Enteric fever was defined as isolation of Salmonella Typhi or Salmonella Paratyphi A, B, and C from the blood and/or stool of patients with fever. Of the 35 patients with imported enteric fever, 28 (80%) had returned from south Asia. Ciprofloxacin-susceptible strains were detected in only 12% of the cases. The isolates showed excellent susceptibility to ampicillin (91%), chloramphenicol (94%), ceftriaxone (97%), and azithromycin (97%). One case of Salmonella Paratyphi B was excluded, and of the remaining 34 patients, 56% were treated with ceftriaxone alone, 26% with ceftriaxone then fluoroquinolone, and 9% with levofloxacin alone. The overall relapse rate was 6.1%; however, among those receiving ceftriaxone monotherapy, the relapse rate was 11% (N = 2). The relapse group was characterized by longer times to treatment initiation (P = 0.035) and defervescence (> 7 days) after treatment initiation (P = 0.022). In such cases, we recommend that ceftriaxone treatment be continued for > 4 days after defervescence or be changed to fluoroquinolone if the strains are found to be susceptible to prevent relapse. Furthermore, ampicillin and chloramphenicol, which are no longer prescribed, may be reconsidered as treatment options in Asia.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Fiebre Tifoidea/tratamiento farmacológico , Fiebre Tifoidea/epidemiología , Adolescente , Adulto , Antibacterianos/uso terapéutico , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Salmonella paratyphi A/efectos de los fármacos , Salmonella paratyphi A/aislamiento & purificación , Salmonella paratyphi B/efectos de los fármacos , Salmonella paratyphi B/aislamiento & purificación , Salmonella paratyphi C/efectos de los fármacos , Salmonella paratyphi C/aislamiento & purificación , Prevención Secundaria , Tokio/epidemiología , Adulto Joven
9.
Infez Med ; 23(2): 174-7, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26110299

RESUMEN

An HIV-infected 49-year-old man was admitted with polyuria, fever, chills and a dull left lumbar pain. Laboratory tests showed increased C-reactive protein while urine analysis and abdomen ultrasound scan were negative. Blood cultures revealed a Salmonella paratyphi B, identified through MALDI-TOF mass spectrometry. Targeted antibiotic therapy with intravenous piperacillin/tazobactam was started and a multi-phase contrast-enhanced abdomen CT-scan was performed at 24 hours from admission showing a saccular aneurysm of the abdominal aorta with a 1 cm penetrating aortic ulcer on posterior wall. The patient underwent emergency vascular surgery at 34 hours from admission for debridement and homo-graft placement of sub-renal aorta, and surgical samples were sent for microbiological analysis. Unfortunately, the patient died on post-surgical day 7 after haemorrhagic shock due to laceration of his graft. Salmonella paratyphi infection can be responsible for sepsis in severely immunosuppressed patients with poorly controlled HIV, requiring careful work-up for cardiovascular involvement.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/complicaciones , Aneurisma Infectado/complicaciones , Aneurisma de la Aorta Abdominal/complicaciones , Infecciones por VIH/complicaciones , Huésped Inmunocomprometido , Salmonella paratyphi B , Procedimientos Quirúrgicos Vasculares/efectos adversos , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico por imagen , Infecciones Oportunistas Relacionadas con el SIDA/cirugía , Aneurisma Infectado/diagnóstico por imagen , Aneurisma Infectado/microbiología , Aneurisma Infectado/cirugía , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Resultado Fatal , Humanos , Masculino , Persona de Mediana Edad , Salmonella paratyphi B/aislamiento & purificación , Choque Hemorrágico/etiología
10.
J Food Prot ; 78(4): 802-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25836408

RESUMEN

Salmonella Paratyphi B dT+ variant (also termed Salmonella Java) and Salmonella Heidelberg are pathogens of public health importance that are frequently isolated from poultry. As a step toward implementing the Colombian Integrated Program for Antimicrobial Resistant Surveillance, this study characterized molecular patterns of Salmonella Paratyphi B dT+ and Salmonella Heidelberg isolated from poultry farms, fecal samples, and retail chicken meat using pulsed-field gel electrophoresis (PFGE). The objective of this study was to determine the genetic relationship among isolates and to determine potential geographically predominant genotypes. Based on PFGE analysis, both serovars exhibited high heterogeneity: the chromosomal DNA fingerprints of 82 Salmonella Paratyphi B dT+ isolates revealed 42 PFGE patterns, whereas the 21 isolates of Salmonella Heidelberg revealed 10 patterns. Similar genotypes of both serovars were demonstrated to be present on farms and in retail outlets. For Salmonella Paratyphi B dT+, closely genetically related strains were found among isolates coming from different farms and different integrated poultry companies within two departments (Santander and Cundinamarca) and also from farms located in the two geographically distant departments. For Salmonella Heidelberg, there were fewer farms with genetically related isolates than for Salmonella Paratyphi B dT+. A possible dissemination of similar genotypes of both serovars along the poultry production chain is hypothesized, and some facilitating factors existing in Colombia are reviewed.


Asunto(s)
Carne/microbiología , Aves de Corral/microbiología , Salmonella enterica/genética , Salmonella paratyphi B/genética , Salmonella/genética , Animales , Pollos , Colombia/epidemiología , Dermatoglifia del ADN , ADN Bacteriano/análisis , Electroforesis en Gel de Campo Pulsado , Heces/microbiología , Genotipo , Salmonella enterica/clasificación , Salmonella enterica/aislamiento & purificación , Salmonella paratyphi B/clasificación , Salmonella paratyphi B/aislamiento & purificación
12.
Mikrobiyol Bul ; 48(2): 191-200, 2014 Apr.
Artículo en Turco | MEDLINE | ID: mdl-24819257

RESUMEN

Although Salmonella enterica serotype Paratyphi B is the less frequently isolated serotype worldwide and in Turkey, it is the most common serotype in our hospital, with a marked increase in 2007. The purpose of this study was to investigate the antibiotic susceptibility and the extended spectrum beta-lactamase (ESBL) profile, and molecular epidemiology of S. Paratyphi B isolates detected in our hospital microbiology laboratory. Seventy isolates identified as S. Paratyphi B from 109 Salmonella isolates obtained from clinical specimens from different patients between October 2005 and December 2012, were included in the study. In addition to conventional methods, isolates were identified using the Phoenix automated microbiology system (Becton Dickinson, USA). Serotyping of the isolates was performed on the basis of slide agglutination and the Kauffmann-White scheme. The antibiotic susceptibility of the isolates was determined using the BD Phoenix' automated system and disk diffusion test. ESBL enzymes were investigated using the combined disk test, isoelectric focusing, polymerase chain reaction (PCR) and sequence analysis. The molecular epidemiology of the 51 isolates obtained between October 2005 and August 2008 was examined with pulsed-field gel electrophoresis (PFGE) using the XbaI enzyme. S. Paratyphi B isolates were obtained from 70 specimens (46 blood, 16 fecal, 4 bone marrow, 2 urine and 2 wound) each from different patients. Resistance to nalidixic acid was determined in 18.6%, resistance to ampicillin, cefotaxime and cefepime in 2.9% and to ceftazidime and co-trimoxazole in 1.4% of the isolates. ESBL production was detected only in two isolates; in one TEM-1 was accompanied by CTX-M-15 and in the other isolate CTX-M-3 was found. Forty-six of the 51 isolates (90%) were found to be genetically related by PFGE and were placed in cluster A. The distribution of the isolates in cluster A revealed six subtypes as A1 (n= 7), A2 (n= 11), A3 (n= 7), A4 (n= 18), A5 (n= 2) and A6 (n= 1). Three different patterns not related to the cluster A were determined in the remaining five isolates (two were B, one of each was C, D and E). In conclusion, although the rate of antibiotic resistance was low in the S. Paratyphi B isolates in our hospital, rare types of ESBLs such as CTX-M-3 and CTX-M-15 were detected in Salmonellae. As far as the current literature is considered, this is the first report in Turkey of blaCTX-M-15 in Salmonella spp. and blaCTX-M-3 genes in S. Paratyphi B. The results may indicate a possible future threat to the treatment of Salmonella infections. Since most of the isolates were genetically related, this might suggest an epidemic in our region.


Asunto(s)
Fiebre Paratifoidea/microbiología , Salmonella paratyphi B/aislamiento & purificación , beta-Lactamasas/metabolismo , Pruebas de Aglutinación , Análisis por Conglomerados , Desoxirribonucleasas de Localización Especificada Tipo II , Pruebas Antimicrobianas de Difusión por Disco , Farmacorresistencia Bacteriana , Electroforesis en Gel de Campo Pulsado , Humanos , Focalización Isoeléctrica , Pruebas de Sensibilidad Microbiana/métodos , Fiebre Paratifoidea/epidemiología , Reacción en Cadena de la Polimerasa , Salmonella paratyphi B/clasificación , Salmonella paratyphi B/efectos de los fármacos , Salmonella paratyphi B/enzimología , Análisis de Secuencia , Serotipificación , Turquía/epidemiología , beta-Lactamasas/genética
13.
FEMS Microbiol Lett ; 355(1): 83-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24725227

RESUMEN

Salmonella enterica serotype Paratyphi B is a globally distributed human-specific pathogen causing paratyphoid fever. The aim of this study was to develop a rapid and reliable polymerase chain reaction (PCR) assay for its detection in food. The SPAB_01124 gene was found to be unique to S. Paratyphi B using comparative genomics. Primers for fragments of the SPAB_01124 gene and the Salmonella-specific invA gene were used in combination to establish a multiplex PCR assay that showed 100% specificity across 45 Salmonella strains (representing 34 serotypes) and 18 non-Salmonella strains. The detection limit was 2.2 CFU mL(-1) of S. Paratyphi B after 12-h enrichment in pure culture. It was shown that co-culture with S. Typhimurium or Escherichia coli up to concentrations of 3.6 × 10(5)  CFU and 3.3 × 10(4)  CFU, respectively, did not interfere with PCR detection of S. Paratyphi B. In artificially contaminated milk, the assay could detect as few as 62 CFU mL(-1) after 8 h of enrichment. In conclusion, comparative genomics was found to be an efficient approach to the mining of pathogen-specific target genes, and the PCR assay that was developed from this provided a rapid, specific, and sensitive method for detection of S. Paratyphi B.


Asunto(s)
Microbiología de Alimentos/métodos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Salmonella paratyphi B/aislamiento & purificación , Cartilla de ADN/genética , ADN Bacteriano/genética , Salmonella paratyphi B/genética , Sensibilidad y Especificidad
14.
J Antimicrob Chemother ; 69(5): 1257-64, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24379303

RESUMEN

OBJECTIVES: To characterize the genetic determinants responsible for extended-spectrum cephalosporin (ESC) resistance of d-tartrate-positive Salmonella enterica subsp. enterica serovar Paratyphi B (serovar Paratyphi B dT+) strains that have emerged in poultry and humans in Belgium during 2008-10. METHODS: The ESC resistance genes among non-redundant serovar Paratyphi B dT+ strains were determined using PCR and sequencing. ESC phenotypes were horizontally transferred by conjugation. Extended-spectrum ß-lactamase (ESBL)- or AmpC-carrying plasmids were typed by PCR-based replicon typing, plasmid multilocus sequence typing and restriction fragment length polymorphism. The genetic relationship of ESC-resistant strains was assessed by XbaI PFGE and multilocus sequence typing. RESULTS: Since 2008, the proportion of serovar Paratyphi B dT+ strains from broiler origin has increased significantly to reach 36.5% in 2010. Among 95 non-duplicate serovar Paratyphi B dT+ strains, 35% were resistant to ESCs. At the same time, a few ESC-resistant serovar Paratyphi B dT+ strains from humans were also detected in Belgium. The most prevalent ESBL gene, blaCTX-M-1, and the AmpC cephalosporinase gene blaCMY-2 were identified on various conjugative IncI1 plasmids of different sequence types and with different additional non-ß-lactam phenotypes. Interestingly, the blaCTX-M-2 gene was located on large multireplicon IncHI2/P plasmids. In addition, highly ESC-resistant strains contained both the ESBL CTX-M-2 and the AmpC CMY-2 encoded by the IncHI2/P and IncI1 plasmids, respectively. All ESC-resistant serovar Paratyphi B dT+ strains belonged to sequence type 28 and showed the common PFGE pattern X8, as well as the chromosomal class 2 integron cassette array dfrA1-sat2-aadA1 previously described in the European poultry-associated serovar Paratyphi B dT+ clonal population. CONCLUSIONS: This study showed that the clonal population of multidrug-resistant serovar Paratyphi B dT+, persisting in broilers in Belgium for the last decade, recently acquired various plasmid-borne ESC resistance determinants, constituting a major concern for public health. Further surveillance programmes and research are an absolute necessity to understand their epidemiology and to propose interventions to limit the spread of ESC- and multidrug-resistant Salmonella spp.


Asunto(s)
Fiebre Paratifoidea/microbiología , Fiebre Paratifoidea/veterinaria , Salmonella paratyphi B/enzimología , Salmonella paratyphi B/aislamiento & purificación , Tartratos/metabolismo , beta-Lactamasas/genética , Animales , Bélgica , Conjugación Genética , Electroforesis en Gel de Campo Pulsado , Transferencia de Gen Horizontal , Humanos , Reacción en Cadena de la Polimerasa , Aves de Corral , Salmonella paratyphi B/genética , Salmonella paratyphi B/metabolismo , Análisis de Secuencia de ADN
15.
J Infect Dev Ctries ; 7(11): 788-95, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24240035

RESUMEN

INTRODUCTION: Enteric fever is a global public health problem, especially in developing countries. Antimicrobial resistance is a major issue enteric fever management. This study examined current pattern of antimicrobial susceptibility among Salmonella enterica isolates from enteric fever cases at a tertiary care centre in New Delhi, India. METHODOLOGY: Blood cultures from patients with enteric fever during January 2010- July 2012 were processed using the BACTEC automated system. Antimicrobial susceptibility was tested using Kirby Bauer's disc diffusion method and/or Phoenix 100 automated system. RESULTS: Of 344 isolates of Salmonella enterica, 266 (77.3%) were S. Typhi, 77 (22.4%) were S. Paratyphi A, and one (0.3%) was S. Paratyphi B. Resistance to nalidixic acid (NA(R)) (96.7%) was most common, followed by ciprofloxacin (37.9%), and azithromycin (7.3%). Multi-drug resistance was observed only in S. Typhi (3.4%). Among NA(R) strains, 61.8% were sensitive, 11.1% were moderately sensitive, and 23.9% were resistant to ciprofloxacin (0.8%, 57.4%, and 37.9% respectively according to revised CLSI breakpoint criteria for ciprofloxacin). Resistance to third-generation cephalosporin was found in seven (2%) strains of S. enterica. CONCLUSION: Increasing rates of nalidixic acid, fluoroquinolone and azithromycin resistance among S. enterica, particularly in S. Paratyphi A strains, is of concern, as S. Paratyphi A infection is becoming increasingly common and is not prevented by current vaccinations. Our results favour use of cefexime or possibly chloramphenicol as first choice for uncomplicated enteric fever. MICs for third-generation cephalosporins and susceptibility pattern must be closely monitored in view of its emerging resistance among Salmonella enterica.


Asunto(s)
Antibacterianos/farmacología , Sangre/microbiología , Farmacorresistencia Bacteriana , Salmonella paratyphi A/efectos de los fármacos , Salmonella paratyphi B/efectos de los fármacos , Salmonella typhi/efectos de los fármacos , Fiebre Tifoidea/microbiología , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , India , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Retrospectivos , Salmonella paratyphi A/aislamiento & purificación , Salmonella paratyphi B/aislamiento & purificación , Salmonella typhi/aislamiento & purificación , Adulto Joven
16.
Pan Afr Med J ; 16: 127, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24839535

RESUMEN

Non-typhoidal salmonella are a rare case of acute acalculouscholecystitis (AAC). Salmonella Paratyphi B, which accounts for one of the less invasive NTS serotypes, has rarely been reported to cause cholecystitis. We describe a case of 65-year old previously healthy man, who present with signs of acute abdomen, due to biliary peritonitis as a complication of acute acalculouscholecystitis caused by Salmonella paratyphi B. Our case illustrates the potential severity of infection with Salmonella Paratyphi B especially in older patient. High index of awarenessshould be considered in endemic areas.


Asunto(s)
Colecistitis Alitiásica/complicaciones , Colecistitis Alitiásica/microbiología , Fiebre Paratifoidea/complicaciones , Peritonitis/complicaciones , Salmonella paratyphi B , Colecistitis Alitiásica/diagnóstico , Colecistitis Alitiásica/cirugía , Enfermedad Aguda , Anciano , Colecistectomía , Humanos , Masculino , Fiebre Paratifoidea/diagnóstico , Fiebre Paratifoidea/cirugía , Peritonitis/diagnóstico , Peritonitis/microbiología , Peritonitis/cirugía , Salmonella paratyphi B/aislamiento & purificación
17.
Malays J Pathol ; 34(1): 35-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22870596

RESUMEN

Serotyping is not sufficient to differentiate between Salmonella species that cause paratyphoid fever from the strains that cause milder gastroenteritis as these organisms share the same serotype Salmonella Paratyphi B (S. Paratyphi B). Strains causing paratyphoid fever do not ferment d-tartrate and this key feature was used in this study to determine the prevalence of these strains among the collection of S. Paratyphi B strains isolated from patients in Malaysia. A total of 105 isolates of S. Paratyphi B were discriminated into d-tartrate positive (dT+) and d-tartrate negative (dT) variants by two lead acetate test protocols and multiplex PCR. The lead acetate test protocol 1 differed from protocol 2 by a lower inoculum size and different incubation conditions while the multiplex PCR utilized 2 sets of primers targeting the ATG start codon of the gene STM3356. Lead acetate protocol 1 discriminated 97.1% of the isolates as S. Paratyphi B dT+ and 2.9% as dT while test protocol 2 discriminated all the isolates as S. Paratyphi B dT+. The multiplex PCR test identified all 105 isolates as S. Paratyphi B dT+ strains. The concordance of the lead acetate test relative to that of multiplex PCR was 97.7% and 100% for protocol 1 and 2 respectively. This study showed that S. Paratyphi B dT+ is a common causative agent of gastroenteritis in Malaysia while paratyphoid fever appears to be relatively uncommon. Multiplex PCR was shown to be a simpler, more rapid and reliable method to discriminate S. Paratyphi B than the phenotypic lead acetate test.


Asunto(s)
Fiebre Paratifoidea/microbiología , Salmonella paratyphi B/aislamiento & purificación , Tartratos/metabolismo , ADN Bacteriano/análisis , Heces/microbiología , Fermentación , Genotipo , Humanos , Malasia , Compuestos Organometálicos , Fiebre Paratifoidea/diagnóstico , Fenotipo , Reacción en Cadena de la Polimerasa/métodos , Salmonella paratyphi B/clasificación , Salmonella paratyphi B/genética , Salmonella paratyphi B/metabolismo , Serotipificación
18.
Appl Environ Microbiol ; 78(20): 7347-57, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22885742

RESUMEN

In this study, the population structure, incidence, and potential sources of human infection caused by the d-tartrate-fermenting variant of Salmonella enterica serovar Paratyphi B [S. Paratyphi B (dT+)] was investigated. In Germany, the serovar is frequently isolated from broilers. Therefore, a selection of 108 epidemiologically unrelated S. enterica serovar Paratyphi B (dT+) strains isolated in Germany between 2002 and 2010 especially from humans, poultry/poultry meat, and reptiles was investigated by phenotypic and genotypic methods. Strains isolated from poultry and products thereof were strongly associated with multilocus sequence type ST28 and showed antimicrobial multiresistance profiles. Pulsed-field gel electrophoresis XbaI profiles were highly homogeneous, with only a few minor XbaI profile variants. All strains isolated from reptiles, except one, were strongly associated with ST88, another distantly related type. Most of the strains were susceptible to antimicrobial agents, and XbaI profiles were heterogeneous. Strains isolated from humans yielded seven sequence types (STs) clustering in three distantly related lineages. The first lineage, comprising five STs, represented mainly strains belonging to ST43 and ST149. The other two lineages were represented only by one ST each, ST28 and ST88. The relatedness of strains based on the pathogenicity gene repertoire (102 markers tested) was mostly in agreement with the multilocus sequence type. Because ST28 was frequently isolated from poultry but rarely in humans over the 9-year period investigated, overall, this study indicates that in Germany S. enterica serovar Paratyphi B (dT+) poses a health risk preferentially by contact with reptiles and, to a less extent, by exposure to poultry or poultry meat.


Asunto(s)
Fiebre Paratifoidea/epidemiología , Fiebre Paratifoidea/microbiología , Aves de Corral/microbiología , Reptiles/microbiología , Salmonella paratyphi B/clasificación , Salmonella paratyphi B/aislamiento & purificación , Tartratos/metabolismo , Animales , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Fermentación , Genotipo , Alemania/epidemiología , Humanos , Incidencia , Epidemiología Molecular , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Fenotipo , Salmonella paratyphi B/genética , Salmonella paratyphi B/metabolismo , Serotipificación
19.
Euro Surveill ; 17(25)2012 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-22748004

RESUMEN

Between September 2010 and October 2011, the Unit of Epidemiology in the Department of Public Health in Bizkaia, Spain identified eight cases of Salmonella Paratyphi B var Java infection and three cases of infection with its possible monophasic variant 4,5,12:b:- dT+. Six cases reported contact with turtles and S. Java was isolated from three of these turtles' habitats. The isolates from the patients and their respective turtles were indistinguishable by pulsed-field gel electrophoresis (PFGE). Although other reptiles can also carry Salmonella, turtles pose a special risk, as they are commonly kept as pets for children. This emphasizes the need to give recommendations regarding ownership and handling of aquatic turtles and other reptiles. As parents are often not aware of the risk of infection associated with the presence of turtles in the household, it would be appropriate to inform potential buyers at points of sale about the risk of infection and measures they can take to minimise this risk.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Fiebre Paratifoidea/epidemiología , Fiebre Paratifoidea/transmisión , Salmonella paratyphi B/aislamiento & purificación , Tortugas/microbiología , Adolescente , Adulto , Animales , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Fiebre Paratifoidea/microbiología , Vigilancia de la Población , España/epidemiología , Adulto Joven
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