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1.
Artigo em Inglês | MEDLINE | ID: mdl-35171091

RESUMO

CDC group non-oxidizer (NO)-1 is the provisional name designated in 1993 for phenotypically similar, Gram-stain-negative bacilli recovered primarily from human wound infections after animal bites. Otherwise, this group has been rarely alluded to in recent literature. CDC NO-1 strains had been described as non-motile, asaccharolytic, oxidase-negative, catalase-positive, nitrate-reducing bacilli, with predominate cellular fatty acids of C10 : 0 3OH, C16 : 1 ω7c, C16 : 0 and C18 : 1 ω7c. Only one 16S rRNA gene sequence deposited in NCBI (accession no. DQ054782) had been identified as CDC group NO-1 prior to this study. That sequence was closely related (>99 % identity) to sequences called 'Xenophilus species' from canine (JN713339) and feline (KM461961) oral microbiomes as well as to sequences derived from human strains (this study). Some of the 11 isolates delineated here were recovered from human wound infections subsequent to cat/dog bites; others were from wounds (links to animal bites not described) and two were recovered from dialysates. After 16S rRNA and whole genome sequencing, the isolates were found to be most closely related to each other but fell into two distinct genera assignable to the family Comamonadaceae, provisionally discussed here as CDC group NO-1 and CDC group NO-1-like. The genomes of CDC group NO-1 isolates ranged from 3.08 to 3.38 MB with G+C contents of 65.08-66.92 %; genomes derived from CDC group NO-1-like strains were smaller, ranging from 2.72 to 2.82 Mb with G+C contents of 62.87-63.0 mol%. Based on a polyphasic study of these bacteria, we describe Vandammella animalimorsus gen. nov., sp. nov. and Franklinella schreckenbergeri gen. nov., sp. nov. for these clusters.


Assuntos
Mordeduras e Picadas , Comamonadaceae , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Mordeduras e Picadas/microbiologia , Gatos , Centers for Disease Control and Prevention, U.S. , Comamonadaceae/classificação , DNA Bacteriano/genética , Cães , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Estados Unidos
2.
Artigo em Inglês | MEDLINE | ID: mdl-34338627

RESUMO

Corynebacterium diphtheriae, Corynebacterium belfantii, Corynebacterium rouxii, Corynebacterium ulcerans, Corynebacterium pseudotuberculosis and Corynebacterium silvaticum are the only taxa from among ~121 Corynebacterium species deemed potentially able to harbour diphtheria tox genes. Subsequently tox-gene bearing species may potentially produce diphtheria toxin, which is linked to fatal respiratory distress if a pharyngeal pseudomembrane is formed or toxaemia develops in those unimmunized or under-immunized. Detection of diphtheria toxin-producing species may also invoke a public health response and contact tracing. Recovery of such species from the respiratory tract or other contaminated sources such as non-healing ulcerative wounds are expedited by use of differential and selective media such as modified Tinsdale medium (MTM). This medium is supplemented with potassium tellurite, which supresses most normal flora present in contaminated specimens, as well as l-cystine and thiosulphate. Most diphtheria-tox-gene bearing species grow well on MTM, producing black colonies with a black halo around each colony. This is due to an ability to produce cystinase in the presence of tellurite, cystine and thiosulphate, resulting in black tellurium deposits being observed in the agar. Other Corynebacterium species may/may not be able to grow at all in the presence of tellurite but if able to grow, will have small beige or brownish colonies which do not exhibit black halos. We describe here an unusual non-tox-gene-bearing isolate, NML 93-0612T, recovered from a human wrist granuloma, which produced black colonies with black halos on MTM agar but was otherwise distinguishable from Corynebacterium species which can bear tox genes. Distinctive features included its unusual colony morphology on MTM and sheep blood agar, by proteomic, biochemical and chemotaxonomic properties and by molecular methods. Its genome contained 2 680 694 bytes, a G+C content of 60.65 mol% with features consistent with the genus Corynebacterium and so represents a new species for which we propose the name Corynebacterium hindlerae sp. nov.


Assuntos
Corynebacterium/classificação , Granuloma/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Canadá , Corynebacterium/isolamento & purificação , Corynebacterium diphtheriae/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Humanos , Pigmentação , Proteômica , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
3.
Int J Syst Evol Microbiol ; 70(5): 3167-3178, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32302276

RESUMO

The Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella (HACEK) group genus Eikenella contained a single species, Eikenella corrodens, for many years. In November 2019, Eikenella exigua was described after recovery from a brain abscess and blood culture in Norway. Coincidentally, characterization of 22 Gram-negative bacteria resembling Eikenella from 17 Canadian patients had been underway. Seven isolates from five patients were conclusively identifiable as E. corrodens. One (NML 120819) was deemed to represent a species of the genus Eikenella most closely related to E. corrodens. Fourteen isolates had 97.6 to 98.8% similarities to E. corrodens by 16S rRNA gene sequencing, forming three distinct groups by genome analyses. The largest contained ten anaerobic isolates from eight patients recovered from blood, brain, bone and other abscesses; upon re-evaluation, this group was found to be most consistent with E. exigua. A second facultatively anaerobic clade consisted of two ocular isolates from one patient and a sinus isolate from a second patient. The third taxon consisted of a single strictly anaerobic blood culture isolate. The novel taxa, like E. corrodens, were poorly reactive biochemically and difficult to discern from each other phenotypically and chemotaxonomically, including by cellular fatty acids. MALDI-TOF (Bruker) and whole-genome sequencing were used to further characterize isolates. Draft genomes for the strains had similar DNA G+C contents (55.38-58.53 mol%) while sizes varied from 1.82 Mb to 2.54 Mb. We propose here emendations of the genus Eikenella and the species Eikenella exigua, as well as describing Eikenella halliae sp. nov. NML 130454T (=LMG 30894T=NCTC 14180T) and Eikenella longinqua sp. nov. NML 02-A-017T (=LMG 30896T=NCTC 14179T), on the basis of these findings.


Assuntos
Sangue/microbiologia , Eikenella/classificação , Filogenia , Bactérias Anaeróbias/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Hemocultura , Canadá , DNA Bacteriano/genética , Eikenella/isolamento & purificação , Ácidos Graxos/química , Humanos , Noruega , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Int J Syst Evol Microbiol ; 70(11): 5676-5685, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32931407

RESUMO

Nine Gram-stain-positive cocci, coccobacilli or short, rod-shaped strains recovered from clinical sources from patients located in two Canadian provinces and one environmental source were extensively studied. Clinical sources included blood cultures, cerebral spinal fluid, lymph node, lung biopsy and peritoneal fluid. Through 16S rRNA gene and whole genome sequencing analyses, the strains were found to cluster into three groups, closest to but distinguished from other genera in the family Propionibacteriaceae. The genomes from these bacteria had high G+C content, ranging from 67.8-69.56 mol%, and genome sizes of 3.02-4.52 Mb. Biochemical and chemotaxonomic properties including branched-chain cellular fatty acids, l-lysine diaminopimelic acid (ll-DAP) and cell-wall type A3γ (ll-DAP-gly) containing ll-DAP, alanine, glycine and glutamic acid were found and so the strains were therefore deemed to be consistent with other new genera in this family. Based on this investigation, we propose Enemella gen. nov., Enemella evansiae sp. nov., Enemella dayhoffiae sp. nov. and Parenemella sanctibonifatiensis gen. nov., sp. nov. for these taxa. Misidentified taxon 'Ponticoccus gilvus' was found to be assignable to Enemella evansiae based on this study.


Assuntos
Líquidos Corporais/microbiologia , Filogenia , Propionibacteriaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Canadá , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Tamanho do Genoma , Genoma Bacteriano , Humanos , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
5.
Int J Syst Evol Microbiol ; 70(12): 6313-6322, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33118921

RESUMO

Twelve isolates recovered from 10 cystic fibrosis/other patient types and a variety of clinical sources, were referred to Canada's National Microbiology Laboratory over 7 years. These were assignable to the genus Pseudoxanthomonas but were unidentifiable to species level. Patients included five males and five females from two geographically separated provinces, ranging in age from 2 months to 84 years. In contrast, most Pseudoxanthomonas species described to date have been derived from water, plants or contaminated soils. By 16S rRNA gene sequencing, the patient strains had ≥99.4 % similarity to each other but only 97.73-98.29 % to their closest relatives, Pseudoxanthomonas spadix or Pseudoxanthomonas helianthi. Bacteria were studied by whole genome sequencing using average nucleotide identity by Blastn, digital DNA-DNA hybridization, average amino acid identity, core genome and single nucleotide variant analyses, MALDI-TOF, biochemical and cellular fatty acid analyses, and by antimicrobial susceptibility testing. Bacterial structures were assessed using scanning and transmission electron microscopy. Strains were strict aerobes, yellowish-pigmented, oxidative, non-motile, Gram-stain-negative bacilli and generally unable to reduce nitrate. Strains were susceptible to most of the antibiotics tested; some resistance was observed towards carbapenems, several cephems and uniformly to nitrofurantoin. The single taxon group observed by 16S rRNA gene sequencing was supported by whole genome sequencing; genomes ranged in size from 4.36 to 4.73 Mb and had an average G+C content of 69.12 mol%. Based on this study we propose the name Pseudoxanthomonas winnipegensis sp. nov. for this cluster. Pseudoxanthomonas spadix DSM 18855T, acquired for this study, was found to be non-motile phenotypically and by electron microscopy; we therefore propose the emendation of Pseudoxanthomonas spadix Young et al. 2007 to document that observation.


Assuntos
Fibrose Cística/microbiologia , Filogenia , Xanthomonadaceae/classificação , Adolescente , Idoso , Idoso de 80 Anos ou mais , Técnicas de Tipagem Bacteriana , Composição de Bases , Canadá , Criança , Pré-Escolar , DNA Bacteriano/genética , Ácidos Graxos/química , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Xanthomonadaceae/isolamento & purificação
6.
BMC Cardiovasc Disord ; 19(1): 312, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31870305

RESUMO

BACKGROUND: Whipple's disease is a clinically relevant multi-system disorder that is often undiagnosed given its elusive nature. We present an atypical case of Whipple's disease involving pan-valvular endocarditis and constrictive pericarditis, requiring cardiac intervention. A literature review was also performed assessing the prevalence of atypical cases of Whipple's disease. CASE PRESENTATION: A previously healthy 56-year-old male presented with a four-year history of congestive heart failure with weight loss and fatigue. Notably, he had absent gastrointestinal symptoms. He went on to develop pan-valvular endocarditis and constrictive pericarditis requiring urgent cardiac surgery. A clinical diagnosis of Whipple's disease was suspected, prompting duodenal biopsy sampling which was unremarkable, Subsequently, Tropheryma whipplei was identified by 16S rDNA PCR on the cardiac valvular tissue. He underwent prolonged antibiotic therapy with recovery of symptoms. CONCLUSIONS: Our study reports the first known case of Whipple's disease involving pan-valvular endocarditis and constrictive pericarditis. A literature review also highlights this presentation of atypical Whipple's with limited gastrointestinal manifestations. Duodenal involvement was limited and the gold standard of biopsy was not contributory. We also highlight the Canadian epidemiology of the disease from 2012 to 2016 with an approximate 4% prevalence rate amongst submitted samples. Routine investigations for Whipple's disease, including duodenal biopsy, in this case may have missed the diagnosis. A high degree of suspicion was critical for diagnosis of unusual manifestations of Whipple's disease.


Assuntos
Endocardite Bacteriana/microbiologia , Doenças das Valvas Cardíacas/microbiologia , Miocardite/microbiologia , Pericardite Constritiva/microbiologia , Tropheryma/isolamento & purificação , Doença de Whipple/microbiologia , Antibacterianos/uso terapêutico , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/cirurgia , Insuficiência Cardíaca/microbiologia , Doenças das Valvas Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/tratamento farmacológico , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Anuloplastia da Valva Mitral , Miocardite/diagnóstico , Miocardite/tratamento farmacológico , Pericardiectomia , Pericardite Constritiva/diagnóstico , Pericardite Constritiva/tratamento farmacológico , Pericardite Constritiva/cirurgia , Ribotipagem , Resultado do Tratamento , Tropheryma/genética , Doença de Whipple/diagnóstico , Doença de Whipple/tratamento farmacológico
7.
Int J Syst Evol Microbiol ; 68(8): 2416-2423, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29889020

RESUMO

A description of an outbreak of necrotizing enterocolitis among neonates, linked to the putative novel species Clostridium neonatale and assignable to the genus Clostridium, was previously reported in brief but that name had never been validly published (Alfa et al. Clin Inf Dis 2002;35:S101-S105). Features of this taxon group and its phylogenetic position with respect to contemporary species in the genus Clostridium were recently reviewed and still found to be unique. Therefore, we provide here a description based on biochemical, chemotaxonomic and antimicrobial susceptibility testing (AST), matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS, 16S rRNA gene sequencing as well as information obtained by whole genome sequencing (WGS) for strains 99A005T and 99A006. Those two C. neonatale strains were essentially identical to each other, with genome sizes of 4 658 596-4 705 520 bp and G+C content of 28.4-28.5 mol% (WGS). AST inferred susceptibility to 14 antibiotics. MALDI-TOF spectra were unique and could potentially be used for identification. The type strain is (NML) LCDC 99A005T [=ATCC BAA-265T=CCUG 46077T=St. Boniface Hospital 30686T]. While performing this review, we found that the names of 24 validly published species assignable to the genus Clostridium had been omitted from the emended description of the genus (Lawson and Rainey Int J Syst Evol Microbiol 2016;66 :1009-1016). Those species are listed in brief here. Lastly, based on this review, we also propose that Eubacterium budayi, Eubacterium nitritogenes and Eubacterium combesii be transferred to the emended genus Clostridium, as Clostridium budayi comb. nov., Clostridium nitritogenes comb. nov. and Clostridium combesii comb. nov., respectively.


Assuntos
Clostridium/classificação , Enterocolite Necrosante/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Clostridium/genética , DNA Bacteriano/genética , Humanos , Recém-Nascido , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Anaerobe ; 44: 128-132, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28279858

RESUMO

Eisenbergiella gen. nov. was proposed in 2014 to describe an obligate anaerobic, structurally Gram-positive but Gram-stain-negative-appearing bacillus recovered from the blood culture of an elderly Israeli man. Here, we describe features for eight blood culture isolates as well one appendix-derived isolate, recovered from seven patients located in two Canadian provinces, which by 16S rRNA gene sequencing, were identifiable as Eisenbergiella tayi, the sole validly- named species in this genus. After whole genome sequencing, isolates were found to be essentially identical (96.8-98.7% identity) to each other and to E. tayi DSM 26961T, after comparison using the ANIb tool and in silico DNA-DNA hydridization. All isolates were observed to have remarkably large genomes (7.1-8.3 Mb) with a G + C content of 46.5%-46.9%.


Assuntos
Clostridiales/classificação , Clostridiales/isolamento & purificação , Infecções por Bactérias Gram-Positivas/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apendicite/microbiologia , Bacteriemia/microbiologia , Técnicas Bacteriológicas , Composição de Bases , Canadá , Clostridiales/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Genoma Bacteriano , Humanos , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Adulto Jovem
10.
Int J Syst Evol Microbiol ; 66(11): 4440-4444, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27498845

RESUMO

A patient strain derived from urine was found by 16S rRNA gene sequencing to be closely related (99.6 % identity) to sequences derived from both Brevibacterium ravenspurgense CCUG 56047T and Brevibacterium massilienseCCUG 53855T. Those species had been described during the same 11 month period in 2008-2009. Further characterization revealed that those isolates could not be readily distinguished from each other biochemically, by cellular fatty acids, antimicrobial susceptibility, MALDI-TOF MS, 16S rRNA gene sequencing or by whole-genome sequence (WGS) analyses. By WGS comparison, these isolates had an aerage nucleotide identity using blastn (ANIb) scores of 95.7 % or higher to each other, DNA G+C content in the range of 62.3 mol%-62.4 mol%, with genome sizes ranging from 2.28×106 to 2.41×106 bases. Based on these data, we propose that the name B. massiliense is a later heterotypic synonym of B. ravenspurgense and provide an emended description of B. ravenspurgense.


Assuntos
Brevibacterium/classificação , Filogenia , Urina/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Brevibacterium/genética , Brevibacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Humanos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Int J Syst Evol Microbiol ; 66(8): 2803-2812, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27045762

RESUMO

Strains of members of the genus Corynebacterium derived from ophthalmologic patients in Japan, Belgium and Switzerland and found to be closely related to-, but distinguishable from Corynebacterium mastitidis by 16S rRNA gene sequencing, were characterized using biochemical, chemotaxonomic, MALDI-TOF mass spectrometry and antimicrobial susceptibility methods and DNA-DNA hybridization as well as by whole-genome sequencing (WGS). Based on this investigation, we describe Corynebacterium lowii sp. nov. and Corynebacterium oculi sp. nov., derived from human ocular specimens, as well as emend the description of Corynebacterium mastitidis. Type strains for these species are: C. lowii R-50085T (=LMG 28276T =CCUG 65815T) and C. oculi R-50187T (=LMG 28277T =CCUG 65816T). DNA G+C content was found to be 62.2 % (by HPLC) and 62.8 % (by WGS) for C. lowii R-50085T, 64.1 % (HPLC) and 64.8 % (WGS) for C. oculi R-50187T and 67.8 % (HPLC) for C. mastitidis LMG 19040T [=S-8T =CCUG 38654T =CECT 4843T =CIP 105509T =DSM 44356T =IFO (NBRC)16160T =JCM 12269T].


Assuntos
Corynebacterium/classificação , Olho/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Bélgica , Corynebacterium/genética , Corynebacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Humanos , Japão , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Suíça
12.
Int J Syst Evol Microbiol ; 63(Pt 6): 2146-2154, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23104363

RESUMO

Corynebacterium propinquum is a Gram-positive rod occasionally recovered from clinical infections which, according to 16S rRNA gene sequencing, is most closely related (>99% sequence similarity) to Corynebacterium pseudodiphtheriticum. The two species are very similar biochemically, commonly differentiated by a single test, the detection of urease, where strains of C. propinquum are described as being urease-non-producing and strains of C. pseudodiphtheriticum are described as urease-producing. In this study, historical and contemporary strains of C. propinquum and C. pseudodiphtheriticum from this laboratory were definitively characterized, which included use of rpoB sequencing. Urease-producing strains of C. propinquum as well as typical urease-non-producing isolates were identified after rpoB sequencing, with six of these being originally identified as C. pseudodiphtheriticum. Based on these observations, we propose emendation of the description of C. propinquum to include strains which produce urease. MALDI-TOF analysis may be a useful tool to differentiate these taxa. Existing commercial databases should be updated to include urease-positive strains of C. propinquum.


Assuntos
Corynebacterium/classificação , Urease/biossíntese , Corynebacterium/enzimologia , DNA Bacteriano/genética , Genes Bacterianos , Dados de Sequência Molecular , Fenótipo , RNA Ribossômico 16S/genética , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
J Clin Microbiol ; 49(11): 4003-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21880960

RESUMO

A toxigenic Corynebacterium diphtheriae biovar mitis sequence type 136 (ST136) strain was recovered from a toe infection of an unvaccinated patient recently returned from India. The isolate was resistant to clindamycin, erythromycin (ermX positive), tetracycline, and trimethoprim-sulfamethoxazole, intermediate to ceftriaxone and cefotaxime, and had high MICs for telithromycin and chloramphenicol but was sensitive to other drugs.


Assuntos
Abscesso/diagnóstico , Antibacterianos/farmacologia , Corynebacterium diphtheriae/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Dermatopatias Bacterianas/diagnóstico , Abscesso/microbiologia , Abscesso/patologia , Adulto , Técnicas de Tipagem Bacteriana , Canadá , Corynebacterium diphtheriae/isolamento & purificação , Difteria/diagnóstico , Difteria/microbiologia , Difteria/patologia , Humanos , Índia , Masculino , Tipagem Molecular , Dermatopatias Bacterianas/microbiologia , Dermatopatias Bacterianas/patologia , Dedos do Pé/microbiologia , Viagem
15.
Diagn Microbiol Infect Dis ; 95(1): 71-76, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31072645

RESUMO

Due to poor diagnostics and increased co-infections, HIV-associated Legionella infections are underreported. We aimed to retrospectively determine the frequency of Legionella infections in bronchoalveolar lavage (BAL) from HIV-associated pneumonia patients hospitalized in Medellin, Colombia, between February 2007 and April 2014. Although culture was negative, 17 BAL (36%) were positive for Legionella by quantitative polymerase chain reaction, most of which were in the Mycobacterium tuberculosis or Pneumocystis jirovecii co-infected patients, and included L. anisa (n = 6), L. bozemanae (n = 4), L. pneumophila (n = 3), and L. micdadei (n = 2). All L. bozemanae and L. micdadei associated with Pneumocystis, while all L. pneumophila associated with M. tuberculosis. Legionella probable cases had more complications and higher mortality rates (P = 0.02) and were rarely administered empirical anti-Legionella therapy while in hospital. Clinicians should be aware of the possible presence of Legionella in HIV and M. tuberculosis or P. jirovecii co-infected patients.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Coinfecção/microbiologia , Legionella/fisiologia , Legionelose/microbiologia , Pneumonia/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adulto , Líquido da Lavagem Broncoalveolar/microbiologia , Coinfecção/epidemiologia , Colômbia/epidemiologia , Feminino , Humanos , Legionella/genética , Legionelose/epidemiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/fisiologia , Pneumocystis carinii/isolamento & purificação , Pneumonia/epidemiologia , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Risco
18.
J Med Microbiol ; 56(Pt 3): 336-341, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17314363

RESUMO

An outbreak of Legionnaires' disease at a long-term care facility in Ontario, Canada from September to October 2005 resulted in the death of 23 residents and the illness of 112 other people. In response, molecular methods were developed to detect Legionella pneumophila in clinical lung samples and to subtype isolates from clinical and environmental samples. The targeted genetic loci included Legionella-specific virulence determinants (mip, icmO, sidA and lidA) and core bacterial determinants (ftsZ, trpS and dnaX). An established amplified fragment length polymorphism typing method provided the first indication of genetic relatedness between strains recovered from clinical samples and strains cultured from environmental samples taken from the outbreak site. These associations were verified using the European Working Group for Legionella Infections sequence-based typing protocol targeting the flaA, pilE, asd, mip, mompS and proA loci. These molecular typing methods confirmed the outbreak source as a contaminated air conditioning cooling tower.


Assuntos
Técnicas de Tipagem Bacteriana , Surtos de Doenças , Legionella pneumophila/classificação , Legionella pneumophila/genética , Legionelose/epidemiologia , Legionelose/microbiologia , Proteínas de Bactérias/genética , Análise por Conglomerados , Impressões Digitais de DNA/métodos , DNA Bacteriano/química , DNA Bacteriano/genética , Humanos , Legionella pneumophila/isolamento & purificação , Pulmão/microbiologia , Epidemiologia Molecular , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Ontário/epidemiologia , Análise de Sequência de DNA , Instituições de Cuidados Especializados de Enfermagem , Fatores de Virulência/genética
19.
BMC Infect Dis ; 5: 4, 2005 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-15667662

RESUMO

BACKGROUND: In the field of clinical mycobacteriology, Mycobacterium tuberculosis (MTB) can be a difficult organism to manipulate due to the restrictive environment of a containment level 3 (CL3) laboratory. Tests for rapid diagnostic work involving smears and molecular methods do not require CL3 practices after the organism has been rendered non-viable. While it has been assumed that after organism deactivation these techniques can be performed outside of a CL3, no conclusive study has consistently confirmed that the organisms are noninfectious after the theoretical 'deactivation' steps. Previous studies have shown that initial steps (such as heating/chemical fixation) may not consistently kill MTB organisms. METHODS: An inclusive viability study (n = 226) was undertaken to determine at which point handling of culture extraction materials does not necessitate a CL3 environment. Four different laboratory protocols tested for viability included: standard DNA extractions for IS6110 fingerprinting, crude DNA preparations for PCR by boiling and mechanical lysis, protein extractions, and smear preparations. For each protocol, laboratory staff planted a proportion of the resulting material to Bactec 12B medium that was observed for growth for 8 weeks. RESULTS: Of the 208 isolates initially tested, 21 samples grew within the 8-week period. Sixteen (7.7%) of these yielded positive results for MTB that included samples of: deactivated culture resuspensions exposed to 80 degrees C for 20 minutes, smear preparations and protein extractions. Test procedures were consequently modified and tested again (n = 18), resulting in 0% viability. CONCLUSIONS: This study demonstrates that it cannot be assumed that conventional practices (i.e. smear preparation) or extraction techniques render the organism non-viable. All methodologies, new and existing, should be examined by individual laboratories to validate the safe removal of material derived from MTB to the outside of a CL3 laboratory. This process is vital to establish in house biosafety-validated practices with the aim of protecting laboratory workers conducting these procedures.


Assuntos
Técnicas de Laboratório Clínico/normas , Contenção de Riscos Biológicos/normas , Viabilidade Microbiana , Mycobacterium tuberculosis , Contenção de Riscos Biológicos/métodos , Impressões Digitais de DNA , DNA Bacteriano/isolamento & purificação , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Saúde Ocupacional , Polimorfismo de Fragmento de Restrição , Medição de Risco
20.
Diagn Microbiol Infect Dis ; 47(3): 503-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14596969

RESUMO

Continuous monitoring systems for the detection of Mycobacterium tuberculosis are reported to have higher contamination rates than traditional radiometric technologies. Multiple decontamination methods have recently been reported in an attempt to optimize contamination rates for these systems. In this study, several decontamination methods for sputum were evaluated using viable colony count and flow cytometry. The decontamination protocols evaluated include N-Acetyl-L-Cysteine-Sodium Hydroxide (NALC-NaOH), modified Petroffs's method, and the Yamane procedure. Several parameters of the NALC-NaOH method were analyzed including final NaOH concentrations of 0.5-3%, NaOH exposure times of 0-30 min, and variations in resuspension media for the resultant pellet. All decontamination methods were performed on pooled and sterilized sputum seeded separately with either a mixture of common contaminating bacteria or M. tuberculosis H37Ra. Viability of organisms following decontamination was assessed by both colony counts and flow cytometric analysis. Flow cytometry viability assays utilized a combination of viability dyes and reference beads to determine viable organism concentrations. The results indicated that no decontamination method was clearly superior, however a concentration of 1-2% NaOH and an increase in the time of NaOH exposure to 30 min will effectively kill contaminating bacteria without significantly affecting the viability of M. tuberculosis H37Ra. While flow cytometry viability analysis did not directly correspond to viable colony counts, it was a useful tool for rapid viability analysis M. tuberculosis.


Assuntos
Citometria de Fluxo/métodos , Mycobacterium tuberculosis/isolamento & purificação , Hidróxido de Sódio/farmacologia , Escarro/microbiologia , Análise de Variância , Técnicas Bacteriológicas , Contagem de Colônia Microbiana , Humanos , Probabilidade , Sensibilidade e Especificidade , Manejo de Espécimes , Tuberculose Pulmonar/diagnóstico
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