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ABSTRACT: Guillain-Barré syndrome (GBS) and Miller-Fisher syndrome (MFS) are correlated with prior infection by Campylobacter jejuni in up to 40% of cases. Nucleotide sequence-based typing of 25 C. jejuni isolates associated with neuropathy permitted robust comparisons with equivalent data from approximately 800 C. jejuni isolates not associated with neuropathy. A total of 13 genetic lineages and 20 flaA short variable region nucleotide sequences were present among the 25 isolates. A minority of isolates (4 of 25) had the flaA short variable region nucleotide sequences that were previously proposed as a marker for GBS-associated isolates. These 4 isolates probably represented the Penner serotype 19 lineage, which has been proposed to have an association with GBS.
Journal of Clinical Microbiology 10/2001; 39(9):3346-9. · 4.15 Impact Factor
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ABSTRACT: From 1997 to 1999 seven isolates of Campylobacter-like organisms from five patients that were exhibiting symptoms of gastroenteritis, including fever, stomach malaise, and diarrhea, were investigated. The organisms were isolated from stool samples and found to exhibit a diverse colony morphology; hence multiple isolates were submitted from one of the patients. All isolates were found to be identical. The organisms were catalase, urease, alkaline phosphatase, and nitrate negative but oxidase and indoxyl acetate positive. They grew at 37 degrees C but not at 42 degrees C, and three of the isolates from two different patients were sensitive to nalidixic acid and cephalothin. Full 16S rRNA sequence analysis not only grouped these organisms within the Helicobacter genus but also differentiated them from previously identified Helicobacter species. The closest relative by phylogenetic analysis was Helicobacter sp. flexispira taxon 1. Electron microscopy showed that these isolates had one or two bipolar flagella; however, the periplasmic fibers, a characteristic of the known Helicobacter sp. flexispira taxa, were not observed. The present isolates also lacked a flagellar sheath, a trait shared with four other Helicobacter spp., H. canadensis, H. mesocricetorum, H. pullorum, and H. rodentium. On the basis of the unique phenotypic properties of these isolates and 16S rRNA sequence analysis, we propose the classification of a new Helicobacter species, Helicobacter winghamensis sp. nov.
Journal of Clinical Microbiology 08/2001; 39(7):2412-7. · 4.15 Impact Factor
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ABSTRACT: To define relationships between Listeria monocytogenes genetic lineages, ribotypes, and serotypes, 235 L. monocytogenes isolates were characterized by serotyping and automated EcoRI ribotyping. Genetic lineage predicted the following serovar clusters: lineage I, comprising serotypes 1/2b, 3b, 3c, and 4b; lineage II, comprising serotypes 1/2a, 1/2c, and 3a; and lineage III, comprising serotypes 4a and 4c. Some EcoRI ribotypes contained multiple serotypes; a subset of these isolates was further differentiated with PvuII ribotyping. Of the 12 resultant EcoRI-PvuII combination types, only 4 contained multiple serotypes, demonstrating the potential of ribotyping for serotype prediction.
Journal of Clinical Microbiology 08/2001; 39(7):2704-7. · 4.15 Impact Factor
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ABSTRACT: Helicobacter pullorum, first detected in the liver and intestinal contents of poultry, was defined as a new species in 1994. This organism has since been isolated from humans with gastroenteritis. Phenotypic as well as genotypic methods have been used to identify H. pullorum associated with cases of human disease.
Clinical isolates were submitted for identification to the National Laboratory for Enteric Pathogens by Provincial Public Health Laboratories within Canada. Phenotypic characterization was conducted using a variety of growth and biochemical tests including oxidase, catalase, indoxyl acetate, H2S production in triple sugar iron (TSI) agar, antimicrobial susceptibility testing, and fatty acid analysis. Genotypic identification was performed using a polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis of a 1-kb fragment of the Helicobacter 16S rRNA gene.
During the last 7 years (1993-1999) a total of 11 isolates of H. pullorum were detected from patients with gastroenteritis for inclusion in this study. Typically, these isolates were oxidase and catalase positive, produced optimal growth at 42 degrees C, and produced H2S in TSI. Of these 11 isolates, 1 showed DNase activity, while another did not produce H2S in TSI, and only 2 showed tolerance to 1% bile. Antimicrobial susceptibility assays indicated that 6 of the 11 strains were resistant to nalidixic acid. The fatty acid profiles of the isolates were similar to each other and provided a distinguishing profile from the other related species. Genetically identical and distinct species-specific restriction fragment-length polymorphism (RFLP) patterns were produced using the restriction enzymes Bsr I and Dde I.
Phenotypic and genotypic procedures were used to identify H. pullorum. Interspecies phenotypic variability was apparent and supported the use of a polyphasic approach for identification. Similarities to the more prominent human pathogens Campylobacter coli and C. lari were also noted. The use of a combination of phenotypic and, in particular, genotypic markers for H. pullorum should prove valuable both for epidemiological investigations and for the diagnosis of disease related to this emerging human pathogen.
Helicobacter 10/2000; 5(3):142-7. · 3.15 Impact Factor
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The Canadian journal of infectious diseases = Journal canadien des maladies infectieuses 08/2000; 11(4):181-6. · 0.76 Impact Factor
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ABSTRACT: We recently analyzed 11 helicobacter isolates cultured from diarrhea patients in Canada. These isolates had been characterized biochemically by restriction fragment length polymorphism (RFLP; AluI, HhaI) analysis and by fatty-acid analysis as Helicobacter pullorum. However, four of the isolates differed biochemically from H. pullorum by their inability to hydrolyze indoxyl acetate and their resistance to nalidixic acid. Using complete 16S rRNA analysis, we determined that these four strains clustered near H. pullorum but had a sequence difference of 2% and therefore represent a novel helicobacter, Helicobacter canadensis. This novel helicobacter could also be distinguished from H. pullorum by RFLP analysis using ApaLI. The number of novel Helicobacter spp. associated with gastrointestinal disease in humans and animals is rapidly increasing. There are now six Helicobacter spp. isolated from diarrheic humans, the other five being H. pullorum, H. canis, "H. rappini," H. fennelliae, and H. cinaedi. This finding highlights the importance of careful molecular analysis in addition to standard biochemical tests in identifying the increasing number of Helicobacter spp. isolated from humans and animals.
Journal of Clinical Microbiology 08/2000; 38(7):2546-9. · 4.15 Impact Factor
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R Ahmed,
G Soule,
W H Demczuk,
C Clark,
R Khakhria,
S Ratnam,
S Marshall,
L K Ng,
D L Woodward,
W M Johnson, F G Rodgers
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ABSTRACT: A major Canada-wide outbreak of gastroenteritis due to Salmonella enterica serotype Enteritidis phage type (PT) 8 occurred in 1998, and this was traced to contaminated cheese in a commercial lunch pack product. Phage typing and pulsed-field gel electrophoresis linked the clinical and cheese isolates of serotype Enteritidis but failed to differentiate outbreak from nonoutbreak PT 8 strains. Further differentiation was made by biotyping based on melibiose fermentation.
Journal of Clinical Microbiology 07/2000; 38(6):2403-6. · 4.15 Impact Factor
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H P Endtz,
C W Ang,
N van Den Braak,
B Duim,
A Rigter,
L J Price,
D L Woodward, F G Rodgers,
W M Johnson,
J A Wagenaar,
B C Jacobs,
H A Verbrugh,
A van Belkum
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ABSTRACT: Campylobacter jejuni has been identified as the predominant cause of antecedent infection in Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS). The risk of developing GBS or MFS may be higher after infection with specific C. jejuni types. To investigate the putative clonality, 18 GBS- or MFS-related C. jejuni strains from The Netherlands and Belgium and 17 control strains were analyzed by serotyping (Penner and Lior), restriction fragment length polymorphism analysis of PCR products of the flaA gene, amplified fragment length polymorphism analysis, pulsed-field gel electrophoresis, and randomly amplified polymorphic DNA analysis. Serotyping revealed 10 different O serotypes and 7 different Lior serotypes, thereby indicating a lack of serotype clustering. Two new O serotypes, O:35 and O:13/65, not previously associated with GBS or MFS were found. Serotype O:19 was encountered in 2 of 18 strains, and none was of serotype O:41. The results of all genotypic methods also demonstrated substantial heterogeneity. No clustering of GBS- or MFS-related strains occurred and no molecular marker capable of separating pathogenic GBS or MFS from non-GBS- or non-MFS-related enteritis strains could be identified in this study. Sialic-acid-containing lipopolysaccharides (LPS) are thought to be involved in the triggering of GBS or MFS through molecular mimicry with gangliosides in human peripheral nerves. Therefore, further characterization of GBS- or MFS-related C. jejuni should target the genes involved in the synthesis of LPS and the incorporation of sialic acid.
Journal of Clinical Microbiology 07/2000; 38(6):2297-301. · 4.15 Impact Factor
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ABSTRACT: A rapid two-step identification scheme based on PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of the 16S rRNA gene was developed in order to differentiate isolates belonging to the Campylobacter, Arcobacter, and Helicobacter genera. For 158 isolates (26 reference cultures and 132 clinical isolates), specific RFLP patterns were obtained and species were successfully identified by this assay.
Journal of Clinical Microbiology 01/2000; 37(12):4158-60. · 4.15 Impact Factor
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H P Endtz,
C W Ang,
Braak,
van den,
B. Duim,
A. Rigter,
L J Price,
D L Woodward, F G Rodgers,
W M Johnson,
J.A. Wagenaar,
B C Jacobs,
H.A. Verburgh,
Belkum
Journal clinical microbiology 38, 2000, 2297-2301. - ISSN 1080-6040.
