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1.
Med Mycol ; 62(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39174488

RESUMO

The Trichophyton mentagrophytes complex comprises a group of dermatophyte fungi responsible for various dermatological infections. The increasing drug resistance of this species complex, especially terbinafine resistance of Trichophyton indotineae, is a major concern in dermatologist practice. This study provides a comprehensive analysis of T. mentagrophytes complex strains isolated from patients in Hue City, Vietnam, focusing on their phenotypic and genetic characteristics, antifungal susceptibility profiles, and molecular epidemiology. Keratinophilic fungi from dermatophytosis culture samples were identified morphologically and phenotypically, with species and genotypes confirmed by internal transcribed spacer sequencing and phylogenetic analysis. Antifungal susceptibility testing was carried out to evaluate their susceptibility to itraconazole, voriconazole, and terbinafine. The 24% (n = 27/114) of superficial mycoses were phenotypically attributed to T. mentagrophytes complex isolates. Trichophyton interdigitale, mainly genotype II*, was predominant (44.4%), followed by T. mentagrophytes genotype III* (22.2%), T. indotineae (14.8%), T. tonsurans (11.2%), and T. mentagrophytes (7.4%). While all isolates were susceptible to itraconazole and voriconazole, half of T. indotineae isolates exhibited resistance to terbinafine, linked to the Phe397Leu mutation in the SQLE protein. This study highlighted the presence of terbinafine-resistant T. indotineae isolates in Vietnam, emphasizing the need to investigate dermatophyte drug resistance and implement effective measures in clinical practice.


Species diversity within the Trichophyton mentagrophytes complex isolated from dermatophytosis in Hue City, Vietnam, was observed. Terbinafine-resistant T. indotineae isolates were detected for the first time in Vietnam, emphasizing the importance of implementing antifungal susceptibility testing to effectively manage and prevent the spread of resistant isolates.


Assuntos
Antifúngicos , Farmacorresistência Fúngica , Genótipo , Testes de Sensibilidade Microbiana , Filogenia , Terbinafina , Tinha , Humanos , Vietnã , Antifúngicos/farmacologia , Terbinafina/farmacologia , Tinha/microbiologia , Arthrodermataceae/efeitos dos fármacos , Arthrodermataceae/genética , Arthrodermataceae/classificação , Arthrodermataceae/isolamento & purificação , Masculino , Análise de Sequência de DNA , Itraconazol/farmacologia , DNA Espaçador Ribossômico/genética , Feminino , Pessoa de Meia-Idade , DNA Fúngico/genética , Epidemiologia Molecular , Adulto , Trichophyton
2.
Antibiotics (Basel) ; 12(9)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37760735

RESUMO

Globally, antibiotic-resistant Klebsiella spp. cause healthcare-associated infections with high mortality rates, and the rise of hypervirulent Klebsiella pneumoniae (hvKp) poses a significant threat to human health linked to community-acquired infections and increasing non-susceptibility. We investigated the phenotypic and genetic features of 36 Klebsiella isolates recovered from invasive infections at Hospital Central of Maputo in Mozambique during one year. The majority of the isolates displayed multidrug resistance (MDR) (29/36) to cephalosporins, gentamicin, ciprofloxacin, and trimethoprim-sulfamethoxazole but retained susceptibility to amikacin, carbapenems, and colistin. Most isolates were ESBLs-producing (28/36), predominantly carrying the blaCTX-M-15 and other beta-lactamase genes (blaSHV, blaTEM-1, and blaOXA-1). Among the 16 genomes sequenced, multiple resistance genes from different antibiotic classes were identified, with blaCTX-M-15, mostly in the ISEcp1-blaCTX-M-15-orf477 genetic environment, co-existing with blaTEM-1 and aac(3)-IIa in five isolates. Our results highlight the presence of polyclonal MDR ESBL-producing K. pneumoniae from eight sequence types (ST), mostly harbouring distinct yersiniabactin within the conjugative integrative element (ICE). Further, we identified susceptible hvKp ST23, O1-K1-type isolates carrying yersiniabactin (ybt1/ICEKp10), colibactin, salmochelin, aerobactin, and hypermucoid locus (rmpADC), associated with severe infections in humans. These findings are worrying and underline the importance of implementing surveillance strategies to avoid the risk of the emergence of the most threatening MDR hvKp.

3.
J Infect Dev Ctries ; 17(4): 550-558, 2023 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-37159900

RESUMO

INTRODUCTION: Candida spp. are responsible for infections ranging from local to systemic, and resistance to antifungal first-line therapy is increasing in non-albicans Candida species. We aimed to determine the etiology of candidiasis and the antifungal resistance of Candida spp. isolated in Hue hospitals, Central-Vietnam. METHODS: Species identification was performed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry supported by fungal internal-transcribed-spacer amplification and sequencing. Antifungal susceptibility testing was performed by disk diffusion method and minimum inhibitory concentrations of azoles, caspofungin, and amphotericin B against C. tropicalis were determined by broth microdilution. Polymorphism of erg11 gene associated with fluconazole resistance was carried out by polymerase chain reaction and sequencing. Multilocus sequence typing (MLST) was used for typing selected C. albicans isolates. RESULTS: Overall, 196 Candida isolates were detected, mostly C. albicans (48%), followed by C. tropicalis (16%), C. parapsilosis (11%), C. glabrata (9%), C. orthopsilosis (6%) and to a lesser extent another eight species. High rates of resistance to fluconazole and voriconazole (18.8%) were observed in C. tropicalis with five isolates co-resistant to both agents. Y132F and S154F missense mutations in the ERG11 protein were associated with fluconazole-resistance in C. tropicalis (67.7%). Resistance to caspofungin was found in one isolate of C. albicans. MLST identified a polyclonal population of C. albicans with multiple diploid sequence types, and with few lineages showing potential nosocomial spread. CONCLUSIONS: Resistance to triazole agents should be considered in C. tropicalis infections in the studied hospitals, and surveillance measures taken to avoid Candida diffusion.


Assuntos
Azóis , Candida albicans , Azóis/farmacologia , Fluconazol , Antifúngicos/farmacologia , Caspofungina , Tipagem de Sequências Multilocus , Vietnã/epidemiologia , Candida/genética , Hospitais
4.
Antibiotics (Basel) ; 12(3)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36978343

RESUMO

Rare information is available on clinical Enterococcus faecium encountered in Sardinia, Italy. This study investigated the antimicrobial susceptibility profiles and genotypic characteristics of E. faecium isolated at the University Hospital of Sassari, Italy, using the Vitek2 system and PCR, MLST, or WGS. Vitek2 revealed two VanB-type vancomycin-resistant Enterococcus faecium (VREfm) isolates (MICs mg/L = 8 and ≥32) but failed to detect vancomycin resistance in one isolate (MIC mg/L ≤ 1) despite positive genotypic confirmation of vanB gene, which proved to be vancomycin resistant by additional phenotypic methods (MICs mg/L = 8). This vanB isolate was able to increase its vancomycin MIC after exposure to vancomycin, unlike the "classic" occult vanB-carrying E. faecium, becoming detectable by Vitek 2 (MICs mg/L ≥ 32). All three E. faecium had highly mutated vanB2 operons, as part of a chromosomally integrated Tn1549 transposon, with common missense mutations in VanH and VanB2 resistance proteins and specific missense mutations in the VanW accessory protein. There were additional missense mutations in VanS, VanH, and VanB proteins in the vanB2-carrying VREfm isolates compared to Vitek2. The molecular typing revealed a polyclonal hospital-associated E. faecium population from Clade A1, and that vanB2-VREfm, and nearly half of vancomycin-susceptible E. faecium (VSEfm) analyzed, belonged to ST117. Based on core genome-MLST, ST117 strains had different clonal types (CT), excluding nosocomial transmission of specific CT. Detecting vanB2-carrying VREfm isolates by Vitek2 may be problematic, and alternative methods are needed to prevent therapeutic failure and spread.

5.
Int J Antimicrob Agents ; 60(4): 106649, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35934230

RESUMO

Extended-spectrum ß-lactamase (ESBL)-producing extraintestinal pathogenic Escherichia coli (ExPEC), particularly high-risk lineages, are responsible for severe infections and increased mortality and hospital costs worldwide, with a major burden in low-income countries. Here we determined the antimicrobial susceptibility and performed whole-genome sequencing of E. coli isolates from extraintestinal infections of patients during 2017-2018 at Maputo Central Hospital (Mozambique). Multidrug resistance was displayed by 71% of isolates (17/24). All isolates resistant to cefotaxime and ceftazidime were positive for ESBL genes (16/24; 67%) and were co-resistant to amoxicillin/clavulanate (14/16; 88%), piperacillin/tazobactam (8/16; 50%), gentamicin (12/16; 75%), trimethoprim/sulfamethoxazole (15/16; 94%) and ciprofloxacin (11/16; 69%). Several major high-risk ExPEC lineages were identified, such as H30Rx-ST131, fimH41-ST131, H24Rx-ST410, ST617, ST361 and ST69 harbouring blaCTX-M-15, and H30R-ST131, ST38 and ST457 carrying blaCTX-M-27. Dissemination of CTX-M transposition units (ISEcp1-blaCTX-M-15-orf477 and ISEcp1-blaCTX-M-27-IS903B) among different sequence types could be occurring through the mobility of IncF plasmids. Additionally, all H24Rx-ST410 isolates carried ISEcp1-mediated blaCMY-2 AmpC and specific mutations in PBP3/OmpC proteins, potentially contributing to carbapenem resistance even in the absence of carbapenemase genes. Genome analysis highlighted a high assortment of ExPEC/UPEC virulence-associated genes mainly involved in adhesion, invasion, iron uptake and secretory systems among isolates, and an ExPEC/EAEC hybrid pathotype (fimH27-ST131_O18-ac:H4) showing the highest virulence gene content. cgMLST showed clonality and closely related isolates, particularly among ST131 and ST410, suggesting hospital-acquired infections and long-term ward persistence. Our study provides new insights into ExPEC clones, urging measures to prevent and contain their diffusion in this hospital and Mozambique.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli Extraintestinal Patogênica , Amoxicilina , Antibacterianos/farmacologia , Carbapenêmicos , Cefotaxima , Ceftazidima , Ciprofloxacina , Ácido Clavulânico , Escherichia coli , Infecções por Escherichia coli/epidemiologia , Proteínas de Escherichia coli/genética , Escherichia coli Extraintestinal Patogênica/genética , Escherichia coli Extraintestinal Patogênica/metabolismo , Gentamicinas , Hospitais , Humanos , Ferro , Moçambique/epidemiologia , Piperacilina , Tazobactam , Combinação Trimetoprima e Sulfametoxazol , beta-Lactamases/genética , beta-Lactamases/metabolismo
6.
PLoS Negl Trop Dis ; 16(8): e0010385, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36040926

RESUMO

Eumycetoma is a chronic debilitating fungal disease endemic to tropical and subtropical regions, with Sudan featuring the highest eumycetoma incidence. Among the 50 species of fungi most commonly associated with eumycetoma Madurella mycetomatis (M. mycetomatis) is often referenced as the most common pathogen. However, there is an enormous knowledge gap related to this neglected disease and its pathogenesis, epidemiological features, and host-specific factors that could contribute to either the host susceptibility and resistance. In this study, we were able to utilize a metagenomic approach and samples collected from clinical black grains (BG) and familiar household environments aimed to assay both the habitat of eumycetoma-associated fungi and its possible connection with eumycetoma patients living in two different eumycetoma endemic villages within the White Nile State of Sudan. DNA sequencing targeting the fungal ITS2 domain was performed on soil, animal dung, housing walls and roofs, and Acacia-species thorn samples and compared with culture-dependent methods of fungal isolation. Additionally, we compared the soil samples obtained in the endemic zone with that from non-endemic zones, including Wagga village in Kassala State and Port Sudan suburb in Port Sudan State. Overall, a total of 392 Amplicon Sequence Variants (ASVs) were detected by ITS2 metagenomics Eumycetoma causative organisms accounted for 10% of total ASVs which included 11 genera: Exserohilum (2%), Aspergillus (1.7%), Curvularia (1%), Alternaria (0.9%), Madurella (0.5%), Fusarium (0.4%), Cladosporium (0.2%) Exophiala (0.15%), and, in a lesser extent, Microascus (0.05%) Bipolaris and Acremonium (0.01%) for each. Only five genera were identified by culture method, which included Fusarium (29%), Aspergillus (28%), Alternaria (2.5%), Bipolaris (1.6%), and Chaetomium (0.8%). M. mycetomatis was detected within all the studied patients' houses, accounting for 0.7% of total sequences. It was the first common eumycetoma-associated agent detected in soil samples and the third common in the dung and wall samples. In contrast, it was not detected in the roof or thorn samples nor in the soils from non-endemic regions. Exserohilum rostratum, Aspergillus spp and Cladosporium spp were detected in all samples. M. mycetomatis and other eumycetoma-associated fungal identified in the patients' black grains (BG) samples by metagenomics were identified in the environmental samples. Only Acremonium alternatum and Falciformispora senegalensis, responsible for eumycetoma in two patients were not detected, suggesting the infections in these patients happened outside these endemic areas. The soil, animal dung, and houses built from the same soil and dung are the main risk factors for M. mycetomatis infection in these endemic villages. Furthermore, the poor hygienic and environmental conditions, walking barefooted, and the presence of animals within the houses increase the risk of M. mycetomatis and other fungi causing eumycetoma.


Assuntos
Madurella , Micetoma , Animais , Metagenômica , Micetoma/microbiologia , Doenças Negligenciadas/diagnóstico , Solo
7.
J Mycol Med ; 32(3): 101291, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35550973

RESUMO

BACKGROUND: Nannizzia incurvata, a species belonging to the Nannizzia gypsea complex, is considered a neglected pathogen. OBJECTIVE: To detected N. incurvata isolates from dermatophytosis patients in Hue city - Viet Nam, and test the antifungal susceptibility of this species. Moreover, fungal capability to produce hydrolytic enzymes was evaluated. METHODS: Patients' samples were collected and cultured on Sabouraud-chloramphenicol-cycloheximide medium. Dermatophytes isolates were initially macroscopically and microscopically identified. ITS PCR-RFLP and ITS rDNA sequences were performed to determine and confirm species. An ITS Neighbor-Joining phylogenetic tree evaluated the genetic relationship among isolates. Fungal hydrolytic enzymes were examined, including lipase, phospholipase and protease. Antifungal susceptibility testing was carried out by the disk diffusion method. MICs of itraconazole, voriconazole, and terbinafine against these isolates were determined by the broth microdilution method. RESULTS: Twelve isolates of N. gypsea complex were preliminary morphologically identified. PCR-RFLP and ITS-rDNA sequencing identified and confirmed dermatophytes as N. incurvata strains, respectively. An evident polymorphism among isolates was highlighted in the phylogenetic tree. All isolates showed the activity of lipase, phospholipase, and protease production. Overall, all N. incurvata isolates were susceptible to itraconazole, voriconazole, clotrimazole, miconazole, and terbinafine. Few isolates were susceptible to griseofulvin, and none of them were susceptible to fluconazole. CONCLUSIONS: There was a presence of polyclonal N. incurvata isolates in dermatophytosis patients from Hue city, identified by PCR-RLFP and confirmed by ITS sequencing. We confirmed PCR-RLFP as a reliable technique to identify this species. Azole and terbinafine are the optimal choices for N. incurvata treatment except for fluconazole.


Assuntos
Arthrodermataceae , Farmacorresistência Fúngica , Tinha , Antifúngicos/farmacologia , Arthrodermataceae/classificação , Arthrodermataceae/efeitos dos fármacos , DNA Ribossômico , Fluconazol , Humanos , Itraconazol , Lipase , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases , Fosfolipases , Filogenia , Terbinafina , Tinha/microbiologia , Vietnã/epidemiologia , Voriconazol
8.
Microb Drug Resist ; 27(12): 1633-1640, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34077257

RESUMO

The development of carbapenem resistance in extraintestinal pathogenic Escherichia coli (ExPEC) has significant clinical implications, particularly in countries where second-line antimicrobials are not readily available, rendering treatments ineffective, and ExPEC infections untreatable. Thus, early detection of high-risk ExPEC lineages and raising awareness of the specific mechanisms underlying carbapenem resistance are mandatory for the selection of appropriate treatment options and the prevention of E. coli spread. This study aims to investigate the phenotypic and genotypic features of the first NDM-5 carbapenemase-producing ExPEC strain isolated from the blood of a patient admitted to the Maputo Central Hospital (MCH), in Mozambique. E. coli SSM100 isolate was identified by MALDI-TOF, it displayed high-level resistance to third generation cephalosporins, carbapenems, fluoroquinolones, and aminoglycosides, performing antimicrobial susceptibilities testing by VITEK 2 system. E. coli SSM100 isolate was classified through whole-genome sequencing as ST405-D-O102: H6, a globally distributed lineage associated with antimicrobial resistance, carrying the blaNDM-5 gene located on an F1:A1:B49 plasmid, coharboring blaCTX-M-15, blaTEM-1, aadA2, sul1, and dfrA12 genes. In addition, mutations in gyrA (S83L and D87N), parC (S80I and E84V), and parE (I529L) conferring fluoroquinolone resistance were also found. Moreover, SSM100 isolate carried 88 virulence genes, of which 28 are reported to be associated with UPEC. The emergence of NDM-5 carbapenemase in a pandemic ST405-D-O102:H6 clone in Mozambique is of great concern. Locations of extended-spectrum ß-lactamase determinants and NDM-5 carbapenemase gene on IncF-plasmid can increase their spread reinforcing the need for antimicrobial surveillance and the urgent introduction of carbapenemase detection tests in diagnostic laboratories of the country.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli Extraintestinal Patogênica/efeitos dos fármacos , Escherichia coli Extraintestinal Patogênica/crescimento & desenvolvimento , Escherichia coli Extraintestinal Patogênica/genética , Escherichia coli Extraintestinal Patogênica/isolamento & purificação , Genes Bacterianos , Genótipo , Testes de Sensibilidade Microbiana , Moçambique , Fenótipo , Plasmídeos , Virulência , Sequenciamento Completo do Genoma , beta-Lactamases/genética
9.
Trans R Soc Trop Med Hyg ; 115(4): 307-314, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33449116

RESUMO

BACKGROUND: Eumycetoma is a chronic subcutaneous granulomatous disease that is endemic in Sudan and other countries. It can be caused by eight different fungal orders. The gold standard diagnostic test is culture, however, culture-independent methods such as imaging, histopathological and molecular techniques can support diagnosis, especially in cases of negative cultures. METHODS: The amplicon-based internal transcribed spacer 2 metagenomic technique was used to study black grains isolated from 14 tissue biopsies from patients with mycetoma. Furthermore, mycological culture and surgical biopsy histopathological examinations of grains were performed. RESULTS: Madurella mycetomatis (n=5) and Falciformispora spp. (n=4) organisms were identified by culture and confirmed by metagenomics. Metagenomics recognised, at the species level, Falciformispora as Falciformispora tompkinsii (n=3) and Falciformispora senegalensis (n=1), while in culture-negative cases (n=5), Madurella mycetomatis (n=3), Falciformispora senegalensis (n=1) and Fusarium spp. (n=1) were identified. Interestingly, the metagenomics results showed a 'consortium' of different fungi in each sample, mainly Ascomycota phylum, including various species associated with eumycetoma. The microbial co-occurrence in eumycetoma showed the co-presence of Madurella with Trichoderma, Chaetomium, Malasseziales and Sordariales spp., while Falciformispora co-presented with Inocybe and Alternaria and was in mutual exclusion with Subramaniula, Aspergillus and Trichothecium. CONCLUSION: Metagenomics provides new insights into the aetiology of eumycetoma in samples with negative culture and into the diversity and complexity of grains mycobiota, calling into question the accuracy of traditional culture for the identification of causative agents.


Assuntos
Micetoma , Negro ou Afro-Americano , Ascomicetos , Humanos , Metagenômica , Micetoma/diagnóstico , Sudão
10.
J Infect Dev Ctries ; 14(11): 1344-1348, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33296350

RESUMO

INTRODUCTION: Imported parasitosis, which do not require an invertebrate vector, are extremely dangerous and can lead to the occurrence of disease in currently parasite free areas. In the present study we report a case of multi-parasitic infection in a young immigrant from Ghana to Italy caused by filaria, Schistosoma sp. and Strongyloides sp. CASE PRESENTATION: A 27-year-old Ghanaian man attended the Hospital of Nuoro (Sardinia), Italy, at the end of August 2015, claiming pain to the kidney and hypertensive crisis; the patient presented with dyspnea and epistaxis, chronic itchy skin of the back, shoulders, arms and legs, anuria and high creatinine, metabolic acidosis and hypereosinophilic syndrome. Serological test for parasitic infections were done, and showed a marked positivity for filaria, Schistosoma sp. and Strongyloides sp. The patient started the treatment immediately with two doses per day of Bassado Antibiotic (tetracycline) for twenty days and then with a single dose of 3 mg of ivermectin that was repeated after 3 months. CONCLUSIONS: Immigrant patients from endemic areas who show clinical signs, such as a general itching on the back, shoulders and arms and legs, should have a thorough history in order to make early diagnosis and prevent further complications. Therefore, general practitioners and doctors in Europe and in other parasitosis non-endemic countries, should consider to test for parasites in any immigrant from endemic countries to aid in establishing the final diagnosis and prevent further complications.


Assuntos
Coinfecção/diagnóstico , Doenças Transmissíveis Importadas/diagnóstico , Doenças Transmissíveis Importadas/parasitologia , Emigrantes e Imigrantes , Filariose/diagnóstico , Esquistossomose/diagnóstico , Estrongiloidíase/diagnóstico , Adulto , Animais , Anti-Helmínticos/uso terapêutico , Coinfecção/tratamento farmacológico , Coinfecção/parasitologia , Filariose/tratamento farmacológico , Gana , Humanos , Itália , Masculino , Schistosoma/efeitos dos fármacos , Strongyloides/efeitos dos fármacos
11.
PLoS Negl Trop Dis ; 13(5): e0007276, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31145740

RESUMO

In this communication, a case of black grain eumycetoma produced by the fungus C. atrobrunneum is reported. The patient was initially misdiagnosed with M. mycetomatis eumycetoma based on the grains' morphological and cytological features. However, further aerobic culture of the black grains generated a melanised fungus identified as C. atrobrunneum by conventional morphological methods and by internal transcribed spacer 2 (ITS2) ribosomal RNA gene sequencing. This is the first-ever report of C. atrobrunneum as a eumycetoma-causative organism of black grain eumycetoma. It is essential that the causative organism is identified to the species level, as this is important for proper patient management and to predict treatment outcome and prognosis.


Assuntos
Chaetomium/isolamento & purificação , Micetoma/microbiologia , Adulto , Antifúngicos/uso terapêutico , Chaetomium/classificação , Chaetomium/genética , Chaetomium/fisiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Humanos , Masculino , Micetoma/diagnóstico , Micetoma/tratamento farmacológico , Filogenia , Sudão
12.
Int J Antimicrob Agents ; 52(5): 586-592, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30012442

RESUMO

Enterococcus faecium has become a globally disseminated nosocomial pathogen mainly because of acquisition and diffusion of virulence factors and multidrug resistance determinants, including glycopeptides, which are some of the last resort antimicrobials used to treat more serious infections common in high-risk patients. In this study we investigated and characterized hospital-associated (HA) E. faecium isolates collected at Hue Central Hospital, Vietnam. Our results highlighted the spread among hospital wards of a surprisingly heterogeneous multidrug-resistant E. faecium population comprising five different CC17-related sequence types (STs), of which 46% VREf carry the vanB gene. Whole genome sequencing of selected E. faecium isolates showed that VREf from different STs carried the same chromosomal integrated Tn1549-like transposon, with a highly mutated vanB2-operon, showing an increased level of vancomycin resistance (VanB phenotype) and able, in one isolate, to confer resistance to teicoplanin (VanA incongruent phenotype). Two unusual vanA/vanB2-type strains were detected within the vanB2-type ST17 population, harbouring a Tn1546-vanA-like transposon in pJEG40-like plasmids. Wg-SNPs-based analysis showed the genetic relatedness of VSEf/VREf of the same STs and indicated lateral exchange of the Tn1549-like element among isolates followed by clonal expansion. Microevolution among ST17 isolates, including the vanA/vanB2-type strains, and inter-wards VREf transmission, were highlighted. The use of teicoplanin is strongly discouraged in the study hospital because of the spreading of Tn1549-vanB2 associated to teicoplanin resistance. A rational use of glycopeptides and effective surveillance measures are required to reduce nosocomial VSEF/VREf spread and to avoid the rise of unusual and misleading VREf genotypes.


Assuntos
Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Enterococcus faecium/isolamento & purificação , Genótipo , Enterococos Resistentes à Vancomicina/isolamento & purificação , Cromossomos Bacterianos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/transmissão , Elementos de DNA Transponíveis , Transmissão de Doença Infecciosa , Farmacorresistência Bacteriana , Enterococcus faecium/genética , Evolução Molecular , Transferência Genética Horizontal , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/transmissão , Hospitais , Humanos , Epidemiologia Molecular , Tipagem Molecular , Mutação , Óperon , Plasmídeos , Polimorfismo de Nucleotídeo Único , Teicoplanina/farmacologia , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/classificação , Enterococos Resistentes à Vancomicina/genética , Vietnã/epidemiologia , Sequenciamento Completo do Genoma
13.
Infect Genet Evol ; 52: 19-25, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28434988

RESUMO

In Vietnam, the high prevalence of Helicobacter pylori infection represents a serious health problem. Virulence genes of H. pylori have been associated to increased risk of severe gastrointestinal diseases and the genetic background differs in geographical areas. We investigated cagA and vacA genotypes of H. pylori from dyspeptic patients from central Vietnam and the correlation with clinical outcomes; we also performed sequencing analysis of partial cagA gene. Overall, 84% of strains were cagA-positive, 75% were East-Asian type with a prevalence of vacAs1i1m1 and vacAs1i1m2 genotypes (66.7% and 33.3%, respectively) and 9% were Western type vacAs1i1m1 (n=4) and vacAs1i1m2 (n=4); vacAs1i2m2 (n=4) and vacAs2i2m2 (n=2) genotypes were associated to cagA-negative. Strains from gastric ulcer and cancer were of East-Asian type, while cagA-negative or Western strains were from gastritis and duodenal ulcer. H. pylori strains from gastric ulcer patients were predominantly vacAs1i1m1 compared to other vacA genotypes (p<0.05). East-Asian type strains vacAs1i1m1 or vacAs1i1m2 were found in gastric cancer patients and also in less severe disease. Phylogenetic tree analysis of CagA sequences showed the co-circulation of H. pylori of different geographical origins with Western sequences closer related to Cambodia, one of the entry of Western strains in Southeast-Asia through human migrations. Sequence analysis revealed in two Western type strains a chimeric CagA-3' region with identity with East-Asian CagA suggesting recombination event in the process of evolution among East-Asian and Western H. pylori strains. Moreover, polymorphism in CagA multimerization (CM) motif was observed including new East-Asian CM motifs. In conclusion, we have found in central Vietnam a geographically dependent diversity of cagA genotype, with higher rates of cagA-negative and Western-type strains compared with other nation's parts that can partly explain the lower risk of gastric cancer. The polymorphism of CM motifs may explain the variability of disease manifestations of vacAs1i1m1 and s1i1m2 East-Asian isolates.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Dispepsia/microbiologia , Técnicas de Genotipagem/métodos , Helicobacter pylori/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Evolução Molecular , Feminino , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Análise de Sequência de DNA , Vietnã , Adulto Jovem
15.
J Infect Dev Ctries ; 9(6): 609-13, 2015 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26142670

RESUMO

Increasing antimicrobial resistance to key antibiotics in Helicobacter pylori has become a main cause of treatment failures in many countries, including Vietnam. For this reason it is advisable to perform antimicrobial sensitivity tests to provide more focused regimens for H. pylori eradication. However, this approach is generally unavailable for H. pylori in Vietnam and the selection of treatment regimens is mainly based on the trend of antibiotic use in the population, resistance development in the region, and history of H. pylori eradication of patients. The aim of this review is to examine the current situation of antimicrobial resistance in Vietnam and suggest management strategies for treatment selection.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Quimioterapia Combinada/métodos , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Vietnã/epidemiologia
16.
J Infect Dev Ctries ; 9(6): 661-4, 2015 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26142678

RESUMO

INTRODUCTION: Diarrheagenic Escherichia coli (DEC) represents one of the leading cause of diarrhoea in developing countries. In this study a molecular approach was applied for the detection of diarrheagenic Escherichia coli (DEC) circulating in Maputo, Mozambique. METHODOLOGY: All isolates were PCR tested for species-specific genes and for 11 molecular markers: stx1, stx2, eae, bfpA, lt, st, ipaH, aap, aggR CVD432 and daaE. RESULTS: Of the 80 E. coli isolated, 74% were potential DEC: 21% EIEC, 19% EPEC, 15% EAEC, 13% ETEC, 5% DAEC and 1% hybrids. CONCLISION: This study revealed the complexity of the etiology of diarrhea caused by pathogenic E. coli in Mozambique, and the risk of the emergence of new pathogenic variants due to the horizontal transmission of pathogenicity factors.


Assuntos
Diarreia/microbiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Genes Bacterianos , Fatores de Virulência/genética , Criança , Pré-Escolar , Diarreia/epidemiologia , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Transferência Genética Horizontal , Variação Genética , Genótipo , Humanos , Lactente , Moçambique/epidemiologia , Reação em Cadeia da Polimerase
17.
J Infect Dev Ctries ; 9(6): 670-3, 2015 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26142680

RESUMO

A clinical case of infection caused by Fasciolopsis buski in a 24 weeks pregnant woman from Vietnam affected by systemic lupus erythematosus (SLE) is reported here. On 22 February 2012 the patient was admitted to Hue Hospital in Hue, Vietnam, with a diagnosis of general illness and suspected acute anaemia. Laboratory analysis indicated possible SLE syndrome and coprological tests demonstrated the presence of F. buski eggs. During hospitalization the patient naturally eliminated the adult form in faeces suggesting the infection had already progressed at least for three months. One month after hospitalization due to the high severity of both SLE and fasciolopsiasis, a medical abortion was carried out and the following day the patient died. Even though infection due to Fasciolopsis buski is rare, this case highlights the importance of an accurate and prompt diagnosis of this infectious agent, which may have saved the foetus and mother's lives.


Assuntos
Fasciolidae/isolamento & purificação , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/patologia , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/patologia , Adulto , Animais , Povo Asiático , Fasciolidae/classificação , Evolução Fatal , Fezes/parasitologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Gravidez , Complicações Infecciosas na Gravidez/parasitologia , Infecções por Trematódeos/parasitologia , Vietnã
18.
Int J Antimicrob Agents ; 45(3): 244-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25499186

RESUMO

Antimicrobial resistance in Helicobacter pylori has increased worldwide and has become a major cause of treatment failure in many countries, including Vietnam. It is advisable to perform an antibiogram to provide optimal regimens for H. pylori eradication. This study evaluated the rate of antibiotic resistance to the four commonly used antibiotics against H. pylori at a tertiary care hospital in Central Vietnam and analysed point mutations in genes related to clarithromycin (CLA) and levofloxacin (LFX) resistance. A total of 92 H. pylori strains from gastric biopsy specimens were tested; 42.4% were resistant to CLA (primary, 34.2%; secondary, 73.7%), 41.3% to LFX (primary, 35.6%; secondary, 63.2%), 76.1% to metronidazole (MTZ) and 1.1% to amoxicillin. Multidrug resistance was observed in 56.5% (primary, 50.7%; secondary, 78.9%) of isolates (P<0.05). The rate of resistance to LFX was significantly higher in females than males (P<0.05). Most of the CLA- and LFX-resistant strains harboured resistance-associated mutations, with common positions at A2143G and T2182C in the 23S rRNA gene and at Asn-87 or Asp-91 in GyrA. Minimum inhibitory concentrations (MICs) increased in strains carrying quadruple mutations in their 23S rRNA gene and in strains with Asn-87 GyrA mutation (P<0.05). One high-level LFX-resistant strain (MIC=32mg/L) had new mutations with a combination of N87A, A88N and V65I. High resistance rates to CLA, MTZ and LFX discourage standard and LFX-based triple therapies as first-line treatment in Vietnam.


Assuntos
Antibacterianos/farmacologia , Claritromicina/farmacologia , Farmacorresistência Bacteriana , Helicobacter pylori/efeitos dos fármacos , Levofloxacino/farmacologia , Metronidazol/farmacologia , Adolescente , Adulto , Idoso , DNA Girase/genética , Feminino , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação Puntual , RNA Ribossômico 23S/genética , Centros de Atenção Terciária , Vietnã , Adulto Jovem
19.
Int J Antimicrob Agents ; 44(2): 156-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25059441

RESUMO

Seven high-risk clones of vancomycin-resistant Enterococcus faecium (VREF) belonging to clonal complex 17 were identified using multilocus sequence typing (MLST) among clinical isolates from Saudi Arabia. Among these isolates, a new hospital-associated sequence type (ST795), VanB(2)-type teicoplanin-resistant strain was detected. Its unusual phenotype resulted from a new combination of mutations in the ddl, vanS and vanW genes, which confirmed the trend of evolution in VanB-type resistance. Furthermore, characteristics of adaptation and persistence in the hospital environment of ST795 were emphasised by the presence of genes and clusters recognised to be specific for hospital-associated VREF.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Enterococcus faecium/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/microbiologia , Teicoplanina/farmacologia , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Análise por Conglomerados , Infecção Hospitalar/microbiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Enterococcus faecium/classificação , Enterococcus faecium/genética , Enterococcus faecium/isolamento & purificação , Genótipo , Humanos , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Mutação , Arábia Saudita , Análise de Sequência de DNA , Enterococos Resistentes à Vancomicina/classificação , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/isolamento & purificação
20.
J Infect Dev Ctries ; 6(11): 786-97, 2012 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-23277504

RESUMO

INTRODUCTION: Wild migratory birds are global distributors of pathogens. Sardinia, Italy, is the second largest Island in the Mediterranean and is a land bridge between Europe and Africa. METHODOLOGY: We designed a surveillance protocol to investigate wild migratory birds for presence, frequency, and type of avian influenza viruses. We collected over 4,000 avian samples and compared three sampling methods, fecal, cloacal, and tracheal, to determine the most productive for virus identification. To determine frequency of infection, RNA was extracted and RT-PCRs for avian influenza virus genes were run. Positive samples were cultivated for live virus, sub typed and sequenced. RESULTS: Forty-four samples were positive for influenza nucleoprotein gene. We identified two previously unidentified H3 subtype strains and found cloacae to have the highest rate of virus identification and fecal sampling to provide quality RNA and repeatable results for determination of virus presence. CONCLUSION: Our investigation provides information on the frequency of Mediterranean avian influenza viruses, and validates the initiation of an avian influenza surveillance protocol.  Taken together with global avian influenza findings, these results give insight into infectious disease distributions which is important for viral pandemic monitoring and design of preventative measures.


Assuntos
Aves/virologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/análise , Vírus da Influenza A Subtipo H3N8/isolamento & purificação , Influenza Aviária/diagnóstico , Sequência de Aminoácidos , Migração Animal , Animais , Cloaca/virologia , Monitoramento Ambiental , Fezes/virologia , Testes de Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H3N8/classificação , Vírus da Influenza A Subtipo H3N8/genética , Influenza Aviária/virologia , Itália , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência
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