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1.
Klin Mikrobiol Infekc Lek ; 27(1): 18-27, 2021 Mar.
Artigo em Tcheco | MEDLINE | ID: mdl-34648646

RESUMO

This draft of guidelines for the laboratory diagnosis of dermatomycoses was developed based on discussion among members of the Czech Society for Medical Microbiology Working Group on Mycology. The document Guidelines for the Laboratory Diagnosis of Dermatomycoses was published for discussion on the Czech Society for Medical Microbiology website on 23 March 2020. Until recently, recommendations concerning this area of laboratory diagnosis in mycology were only limited to information in manuals and no comprehensive and systematic document concerning these issues was available. In an effort to fill the gap, members of the working group developed recommendations covering various laboratory aspects of mycology, from obtaining a proper history, to adequate sampling techniques, sample analyses using conventional microscopy and culture techniques, to interpretation of results. Additional information was on the diagnostic potential of novel, modern technology, in particular molecular genetic methods and mass spectrometry. The recently developed European standards for testing the susceptibility of dermatophytes to antifungals were also included in the recommendations. The document will be regularly updated based on new findings.


Assuntos
Dermatomicoses , Micologia , Antifúngicos , República Tcheca , Dermatomicoses/diagnóstico , Humanos , Laboratórios
2.
Med Mycol ; 54(7): 714-24, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27161789

RESUMO

Despite advances in the treatment of invasive fungal diseases (IFD), mortality rates remain high. Moreover, due to the expanding spectrum of causative agents, fast and accurate pathogen identification is necessary. We designed a panfungal polymerase chain reaction (PCR), which targets the highly variable ITS2 region of rDNA genes and uses high resolution melting analysis (HRM) for subsequent species identification. The sensitivity and specificity of this method was tested on a broad spectrum of the most clinically important fungal pathogens including Aspergillus spp., Candida spp. and mucormycetes. Despite the fact that fluid from bronchoalveolar lavage (BAL) is one of the most frequently tested materials there is a lack of literature sources aimed at panfungal PCR as an IFD diagnostic tool from BAL samples. The applicability of this method in routine practice was evaluated on 104 BAL samples from immunocompromised patients. Due to high ITS region variability, we obtained divergent melting peaks for different fungal species. Thirteen out of 18 patients with proven or probable IFD were positive. Therefore, the sensitivity, specificity, positive predictive value and negative predictive value of our method were 67%, 100%, 100%, and 94%, respectively. In our assay, fungal pathogens identification is based on HRM, therefore omitting the expensive and time consuming sequencing step. With the high specificity, positive and negative predictive values, short time needed to obtain a result, and low price, the presented assay is intended to be used as a quick screening method for patients at risk of IFD.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , DNA Fúngico/genética , Fungos/isolamento & purificação , Pneumopatias Fúngicas/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Temperatura de Transição , DNA Fúngico/química , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Feminino , Fungos/classificação , Fungos/genética , Humanos , Pneumopatias Fúngicas/microbiologia , Masculino , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
3.
Mycoses ; 59(1): 48-55, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26661324

RESUMO

Disseminated fusariosis is a life-threatening, invasive, opportunistic infection in immunocompromised patients, especially those with haematological malignancies. The prognosis is poor because these fungi are resistant to many of the available antifungal agents. We present a case of disseminated fusariosis caused by Fusarium proliferatum in a patient with severe aplastic anaemia complicated by a secondary infection of Aspergillus flavus, with a fatal outcome. We also review the documented Fusarium infections in immunocompromised hosts.


Assuntos
Anemia Aplástica/complicações , Antifúngicos/uso terapêutico , Fusariose/diagnóstico , Hospedeiro Imunocomprometido , Infecções Oportunistas/diagnóstico , Triazóis/uso terapêutico , Antifúngicos/farmacologia , Aspergilose/complicações , Aspergilose/microbiologia , Aspergillus flavus/efeitos dos fármacos , Aspergillus flavus/isolamento & purificação , Coinfecção , Evolução Fatal , Fusariose/complicações , Fusariose/tratamento farmacológico , Fusariose/microbiologia , Fusarium/efeitos dos fármacos , Fusarium/isolamento & purificação , Humanos , Masculino , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/microbiologia , Adulto Jovem
4.
J Clin Microbiol ; 52(8): 2824-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24850354

RESUMO

Rapid differential diagnostics of pulmonary infiltrates suspected of invasive fungal disease in an immunocompromised host and early initiation of effective antifungal therapy are crucial for patient outcomes. There are no serological tests available to detect mucormycetes; therefore, PCR-based methods are highly suitable. We validated our previously published PCR followed by high-resolution melt analysis (PCR/HRMA) to detect Rhizopus spp., Rhizomucor pusillus, Lichtheimia corymbifera, and Mucor spp. in bronchoalveolar lavage (BAL) samples from immunocompromised patients who were at risk of invasive fungal disease. All PCR/HRMA-positive samples were retested using novel real-time quantitative PCR (RQ PCR) assays specific to the species identified. In total, between January 2009 and December 2012 we analyzed 99 BAL samples from 86 patients with pulmonary abnormalities using PCR/HRMA. Ninety (91%) BAL samples were negative, and 9 (9%) samples were positive. The sensitivity and specificity of PCR/HRMA were 100% and 93%, respectively. By combining the positive results of PCR/HRMA with positive RQ PCR results, the specificity was raised to 98%. PCR/HRMA, due to its high negative predictive value (99%), represents a fast and reliable tool for routine BAL sample screening for the differential diagnosis of pulmonary infiltrates in immunocompromised patients for the four most clinically important mucormycetes.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Pneumopatias Fúngicas/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Mucorales/classificação , Mucorales/isolamento & purificação , Mucormicose/diagnóstico , Reação em Cadeia da Polimerase/métodos , Feminino , Humanos , Hospedeiro Imunocomprometido , Pneumopatias Fúngicas/microbiologia , Masculino , Mucormicose/microbiologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Temperatura de Transição
5.
Folia Microbiol (Praha) ; 69(4): 903-911, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38647991

RESUMO

Patients with burn injury and inhalation injury are highly susceptible to infectious complications, including opportunistic pathogens, due to the loss of skin cover and mucosal damage of respiratory tract as well as the disruption of homeostasis. This case report, a 34-year-old man suffered critical burns, provides the first literature description of triple-impact immunoparalysis (critical burns, inhalation injury, and SARS-CoV-2 infection), leading to a lethal multifocal infection caused by several fungi including very rare environmental representatives Metschnikowia pulcherrima and Wickerhamomyces anomalus. The co-infection by these common environmental yeasts in a human is unique and has not yet been described in the literature. Importantly, our patient developed refractory septic shock and died despite targeted antifungal therapy including the most potent current antifungal agent-isavuconazole. It can be assumed that besides immunoparalysis, effectiveness of therapy by isavuconazole was impaired by the large distribution volume in this case. As this is a common situation in intensive care patients, routine monitoring of plasmatic concentration of isavuconazole can be helpful in personalization of the treatment and dose optimization. Whatmore, many fungal species often remain underdiagnosed during infectious complications, which could be prevented by implementation of new methods, such as next-generation sequencing, into clinical practice.


Assuntos
Antifúngicos , COVID-19 , Humanos , Adulto , Masculino , Antifúngicos/uso terapêutico , COVID-19/imunologia , COVID-19/complicações , Coinfecção/microbiologia , Coinfecção/tratamento farmacológico , Coinfecção/imunologia , Queimaduras/complicações , Queimaduras/microbiologia , Sepse/tratamento farmacológico , Sepse/microbiologia , Sepse/imunologia , Evolução Fatal , SARS-CoV-2/imunologia , Nitrilas/uso terapêutico , Micoses/tratamento farmacológico , Micoses/microbiologia , Micoses/imunologia , Micoses/diagnóstico , Piridinas/uso terapêutico , Triazóis/uso terapêutico , Saccharomycetales/genética , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/imunologia
6.
J Hematol Oncol ; 17(1): 63, 2024 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-39113112

RESUMO

Invasive fungal disease (IFD) presents a life-threatening condition in immunocompromised patients, thus often prompting empirical administration of antifungal treatment, without adequate mycological evidence. Over the past years, wide use of antifungal prophylaxis resulted in decreased occurrence of IFD but has contributed to changes in the spectrum of fungal pathogens, revealing the occurrence of previously rare fungal genera causing breakthrough infections. The expanding spectrum of clinically relevant fungal pathogens required the implementation of screening approaches permitting broad rather than targeted fungus detection to support timely onset of pre-emptive antifungal treatment. To address this diagnostically important aspect in a prospective setting, we analyzed 935 serial peripheral blood (PB) samples from 195 pediatric and adult patients at high risk for IFD, involving individuals displaying febrile neutropenia during treatment of hematological malignancies or following allogeneic hematopoietic stem cell transplantation. Two different panfungal-PCR-screening methods combined with ensuing fungal genus identification by Sanger sequencing were employed. In the great majority of PB-specimens displaying fungal DNAemia, the findings were transient and revealed fungi commonly regarded as non-pathogenic or rarely pathogenic even in the highly immunocompromised patient setting. Hence, to adequately exploit the diagnostic potential of panfungal-PCR approaches for detecting IFD, particularly if caused by hitherto rarely observed fungal pathogens, it is necessary to confirm the findings by repeated testing and to identify the fungal genus present by ensuing analysis. If applied appropriately, panfungal-PCR-screening can help prevent unnecessary empirical therapy, and conversely, contribute to timely employment of effective pre-emptive antifungal treatment strategies.


Assuntos
DNA Fúngico , Neutropenia Febril , Hospedeiro Imunocomprometido , Humanos , Estudos Prospectivos , Adulto , Neutropenia Febril/microbiologia , DNA Fúngico/análise , Feminino , Masculino , Criança , Adolescente , Pessoa de Meia-Idade , Prevalência , Adulto Jovem , Idoso , Fungos/isolamento & purificação , Fungos/genética , Neoplasias Hematológicas/complicações , Pré-Escolar , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções Fúngicas Invasivas/epidemiologia , Infecções Fúngicas Invasivas/prevenção & controle , Infecções Fúngicas Invasivas/etiologia , Infecções Fúngicas Invasivas/microbiologia , Antifúngicos/uso terapêutico
7.
Mycoses ; 56(2): 101-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22594314

RESUMO

There are discrepancies in the retrospective studies published in literature of whether or not bacteraemia could lead to false positivity of 1,3-ß-D (BG) glucan assay. We performed, for the first time, a prospective study evaluating the role of bacterial bloodstream infection to the reactivity of BG assay. Twenty-six episodes of bacteraemia that occurred in high-risk haematological patients were included in our study. Consecutive BG levels >80 pg ml(-1) were required for test positivity. Only 2 of 26 patients were BG positive - both with IFDs. Thus, we prospectively did not prove bacteraemia as the source of cross reactivity of BG assay in haematological patients.


Assuntos
Bacteriemia/sangue , Bactérias/metabolismo , beta-Glucanas/sangue , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Bactérias/isolamento & purificação , Humanos , Estudos Prospectivos , Estudos Retrospectivos , beta-Glucanas/metabolismo
8.
Microbiol Spectr ; 11(4): e0510722, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37306567

RESUMO

The MLST scheme currently used for Enterococcus faecium typing was designed in 2002 and is based on putative gene functions and Enterococcus faecalis gene sequences available at that time. As a result, the original MLST scheme does not correspond to the real genetic relatedness of E. faecium strains and often clusters genetically distant strains to the same sequence types (ST). Nevertheless, typing has a significant impact on the subsequent epidemiological conclusions and introduction of appropriate epidemiological measures, thus it is crucial to use a more accurate MLST scheme. Based on the genome analysis of 1,843 E. faecium isolates, a new scheme, consisting of 8 highly discriminative loci, was created in this study. These strains were divided into 421 STs using the new MLST scheme, as opposed to 223 STs assigned by the original MLST scheme. The proposed MLST has a discriminatory power of D = 0.983 (CI95% 0.981 to 0.984), compared to the original scheme's D = 0.919 (CI95% 0.911 to 0.927). Moreover, we identified new clonal complexes with our newly designed MLST scheme. The scheme proposed here is available within the PubMLST database. Although whole genome sequencing availability has increased rapidly, MLST remains an integral part of clinical epidemiology, mainly due to its high standardization and excellent robustness. In this study, we proposed and validated a new MLST scheme for E. faecium, which is based on genome-wide data and thus reflects the tested isolates' more accurate genetic similarity. IMPORTANCE Enterococcus faecium is one of the most important pathogens causing health care associated infections. One of the main reasons for its clinical importance is a rapidly spreading resistance to vancomycin and linezolid, which significantly complicates antibiotic treatment of infections caused by such resistant strains. Monitoring the spread and relationships between resistant strains causing severe conditions represents an important tool for implementing appropriate preventive measures. Therefore, there is an urgent need to establish a robust method enabling strain monitoring and comparison at the local, national, and global level. Unfortunately, the current, extensively used MLST scheme does not reflect the real genetic relatedness between individual strains and thus does not provide sufficient discriminatory power. This can lead directly to incorrect epidemiological measures due to insufficient accuracy and biased results.


Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Humanos , Enterococcus faecium/genética , Tipagem de Sequências Multilocus/métodos , Infecções por Bactérias Gram-Positivas/epidemiologia , Antibacterianos , Sequenciamento Completo do Genoma
9.
Microbiol Spectr ; 11(1): e0357122, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36629420

RESUMO

The Pseudomonas aeruginosa population has a nonclonal epidemic structure. It is generally composed of a limited number of widespread clones selected from a background of many rare and unrelated genotypes recombining at high frequency. Due to the increasing prevalence of nosocomial infections caused by multidrug-resistant/extensively drug-resistant (MDR/XDR) strains, it is advisable to implement infection control measures. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) are considered the gold standard methods in bacterial typing, despite being limited by cost, staff, and instrumental demands. Here, we present a novel mini-MLST scheme for P. aeruginosa rapid genotyping based on high-resolution melting analysis. Using the proposed mini-MLST scheme, 3,955 existing sequence types (STs) were converted into 701 melting types (MelTs), resulting in a discriminatory power of D = 0.993 (95% confidence interval [CI], 0.992 to 0.994). Whole-genome sequencing of 18 clinical isolates was performed to support the newly designed mini-MLST scheme. The clonal analysis of STs belonging to MelTs associated with international high-risk clones (HRCs) performed by goeBURST software revealed that a high proportion of the included STs are highly related to HRCs and have also been witnessed as responsible for serious infections. Therefore, mini-MLST provides a clear warning for the potential spread of P. aeruginosa clones recognized as MDR/XDR strains with possible serious outcomes. IMPORTANCE In this study, we designed a novel mini-MLST typing scheme for Pseudomonas aeruginosa. Its great discriminatory power, together with ease of performance and short processing time, makes this approach attractive for prospective typing of large isolate sets. Integrating the novel P. aeruginosa molecular typing scheme enables the development and spread of MDR/XDR high-risk clones to be investigated.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Tipagem de Sequências Multilocus , Epidemiologia Molecular/métodos , Estudos Prospectivos , Genótipo , Células Clonais , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia
10.
J Clin Microbiol ; 50(3): 602-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22189110

RESUMO

We developed and assessed the diagnostic value of a novel quantitative nested real-time (QNRT) PCR assay targeting the internal transcribed spacer region of ribosomal DNA (rDNA) in a guinea pig model of invasive pulmonary aspergillosis. Groups of 5 immunosuppressed animals that were infected using an aerosol chamber with Aspergillus fumigatus conidia were humanely terminated 1 h postinoculation and at days 3, 5, 7, and 11 postchallenge, and lung tissue, bronchoalveolar lavage (BAL) fluid, whole blood, and serum samples were collected. The QNRT PCR results obtained with the serum and BAL fluid were compared to those achieved with galactomannan and (1→3)-ß-d-glucan assays. High fungal burden levels were detected by QNRT PCR in both lung tissue and BAL fluid in all infected animals at each time point, and the sensitivity of each assay in BAL fluid was 100% by day 3 and remained so through the remainder of the study. The sensitivity of detection of fungi in whole blood and serum samples was significantly lower, and some samples remained negative by all three assays despite the advanced stage of the infection. From these data, we can conclude that this novel QNRT PCR method was highly sensitive for the detection of A. fumigatus from different types of samples in this model. In addition, BAL fluid samples appeared to be the most suitable for the early diagnosis of invasive pulmonary aspergillosis. When testing serum, the use of a combination of available assays may increase the possibility of early detection of this opportunistic mycosis.


Assuntos
Aspergillus fumigatus/isolamento & purificação , Aspergilose Pulmonar Invasiva/microbiologia , Mananas/análise , Micologia/métodos , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , beta-Glucanas/análise , Animais , Líquido da Lavagem Broncoalveolar/microbiologia , Contagem de Colônia Microbiana/métodos , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Modelos Animais de Doenças , Galactose/análogos & derivados , Cobaias , Aspergilose Pulmonar Invasiva/patologia , Pulmão/microbiologia , Masculino , Proteoglicanas , Sensibilidade e Especificidade
11.
Mycoses ; 55(6): 483-92, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22429709

RESUMO

The objective of this retrospective study was to evaluate results from voriconazole therapeutic drug monitoring (TDM) in haematological patients in routine clinical practice. Between 2005 and 2010, 1228 blood samples were obtained from 264 haematological patients (median 3 samples/patient; range 1-27) receiving voriconazole for targeted/preemptive treatment of invasive aspergillosis (IA) (46.3% of samples), empirical therapy (12.9%) or prophylaxis (40.8%). A high-pressure liquid chromatography assay was used to analyse voriconazole concentrations. Clinical and laboratory data were analysed retrospectively. The median of the detected voriconazole plasma concentration was 1.00 µg ml(-1) (range <0.20-13.47 µg ml(-1)). Significant inter- and intra-patients variability of measured concentrations (81.9% and 50.5%) were identified. With the exception of omeprazole administration, there was no relevant relationship between measured voriconazole concentrations and drug dose, route administration, age, gender, CYP2C19*2 genotype, gastrointestinal tract abnormality, administration via nasogastric tube, serum creatinine, and liver enzymes. However, per patient analysis identified significant role of individual voriconazole dose and drug form change on measured plasma concentration. Measured voriconazole concentrations did not correlate with the treatment outcome of patients with IA. We only identified a limited number of adverse events related to voriconazole therapy; however, the median plasma concentration was not different from concentrations measured in samples without reported toxicity. Our retrospective study has suggested that routine monitoring of voriconazole plasma concentrations has probably only a limited role in daily haematological practice.


Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/sangue , Aspergilose/tratamento farmacológico , Monitoramento de Medicamentos , Doenças Hematológicas/tratamento farmacológico , Pirimidinas/administração & dosagem , Pirimidinas/sangue , Triazóis/administração & dosagem , Triazóis/sangue , Adolescente , Adulto , Idoso , Antifúngicos/efeitos adversos , Hidrocarboneto de Aril Hidroxilases/genética , Aspergilose/complicações , Aspergilose/genética , Citocromo P-450 CYP2C19 , Relação Dose-Resposta a Droga , Feminino , Doenças Hematológicas/complicações , Doenças Hematológicas/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Pirimidinas/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Triazóis/efeitos adversos , Voriconazol , Adulto Jovem
12.
Klin Mikrobiol Infekc Lek ; 18(4): 96-101, 2012 Aug.
Artigo em Tcheco | MEDLINE | ID: mdl-23172020

RESUMO

Invasive fungal diseases (IFD) are a life-threatening infectious complications in immunocompromised patients and are associated with high rate of morbidity and mortality. The most common invasive mycosis in patients who underwent an allogeneic hematopoietic stem cell transplantation is invasive aspergilosis (IA), most frequently caused by the clinically dominant species Aspergillus fumigatus and, rarely, also by Aspergillus flavus, Aspergillus terreus and Aspergillus niger. In recent years, other related Aspergillus species were also reported to cause IFD, phenotypically similar to A. fumigatus and moreover, frequently exhibiting resistance towards various antifungals. For example, it is Aspergillus lentulus, Aspergillus viridinutans, Neosartoya fischeri, etc. Classical microbiological methods such as direct microscopy or culture are usually used for the identification of Aspergillus species. The application of PCR-based molecular techniques and monitoring of secondary metabolites production enable detection and identification of species, which are not distinguishable solely by their morphology. PCR methods are also useful for molecular strain typing of aspergilli and can reveal the genetic diversity of isolates.


Assuntos
Aspergilose/diagnóstico , Hospedeiro Imunocomprometido , Aspergilose/microbiologia , Aspergillus/classificação , Humanos
13.
Klin Mikrobiol Infekc Lek ; 18(4): 109-14, 2012 Aug.
Artigo em Tcheco | MEDLINE | ID: mdl-23172022

RESUMO

Methods of molecular genetics offer rapid and sensitive detection and identification of fungal pathogens. The currently used methods are based mainly on PCR. With regard to the ubiquitous presence of fungi, it is important to prevent contamination during the whole process, from sampling to laboratory analyses. Molecular genetic methods are not included among the EORTC/MSG criteria used for the diagnosis of invasive fungal diseases since interlaboratory standardization is still missing. Another reason is the use of different target genes for PCR. ITS sequences from rDNA clusters are recommended for DNA barcoding of fungi. The use of DNA sequencing for identification of fungi in clinical samples has certain limitations and interpretation of results could be problematic in some cases. DNA sequences are searched and compared in public databases on the Internet, the best known of them being the GenBank. However, more reliable data for identification of fungi are offered by specialized mycological databases.


Assuntos
Fungos/genética , Técnicas de Diagnóstico Molecular , Micoses/diagnóstico , DNA Fúngico/genética , Fungos/classificação , Humanos , Biologia Molecular , Micoses/microbiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
14.
Microbiol Spectr ; 10(1): e0181721, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138156

RESUMO

Staphylococcus aureus is a major bacterial human pathogen that causes a wide variety of clinical manifestations. The main aim of the presented study was to determine and optimize a novel sequencing independent approach that enables molecular typing of S. aureus isolates and elucidates the transmission of emergent clones between patients. In total, 987 S. aureus isolates including both methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) isolates were used to evaluate the novel typing approach combining high-resolution melting (HRM) analysis of multilocus sequence typing (MLST) genes (mini-MLST) and spa gene (spa-HRM). The novel approach's discriminatory ability was evaluated by whole-genome sequencing (WGS). The clonal relatedness of tested isolates was set by the BURP and BURST approach using spa and MLST data, respectively. Mini-MLST classified the S. aureus isolates into 38 clusters, followed by spa-HRM classifying the isolates into 101 clusters. The WGS proved HRM-based methods to effectively differentiate between related S. aureus isolates. Visualizing evolutionary relationships among different spa-types provided by the BURP algorithm showed comparable results to MLST/mini-MLST clonal clusters. We proved that the combination of mini-MLST and spa-HRM is rapid, reproducible, and cost-efficient. In addition to high discriminatory ability, the correlation between spa evolutionary relationships and mini-MLST clustering allows the variability in population structure to be monitored. IMPORTANCE Rapid and cost-effective molecular typing tools for Staphylococcus aureus epidemiological applications such as transmission tracking, source attribution and outbreak investigations are highly desirable. High-resolution melting based methods are effective alternative to those based on sequencing. Their good reproducibility and easy performance allow prospective typing of large set of isolates while reaching great discriminatory power. In this study, we established a new epidemiological approach to S. aureus typing. This scheme has the potential to greatly improve epidemiological investigations of S. aureus.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Controle de Infecções , Tipagem Molecular/métodos , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Tipagem de Sequências Multilocus , Estudos Prospectivos , Reprodutibilidade dos Testes , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Sequenciamento Completo do Genoma
15.
J Fungi (Basel) ; 7(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207136

RESUMO

Infectious complications are responsible for the majority of mortalities and morbidities of patients with critical burns. Although bacteria are the predominant etiological agents in such patients, yeasts and fungi have become relatively common causes of infections over the last decade. Here, we report a case of a young man with critical burns on 88% TBSA (total body surface area) arising as a part of polytrauma. The patient's history of orthotopic liver transplantation associated with the patient's need to use combined immunosuppressant therapy was an additional complication. Due to deep burns in the forearm region, we have (after a suitable wound bed preparation) applied a new bi-layered dermal substitute. The patient, however, developed a combined fungal infection in the region of this dermal substitute caused by Trichoderma longibrachiatum and Aspergillus fischeri (the first case ever reported). The infection caused the loss of the split-thickness skin grafts (STSGs); we had to perform repeated hydrosurgical and mechanical debridement and a systemic antifungal treatment prior to re-application of the STSGs. The subsequent skin transplant was successful.

16.
Sci Rep ; 11(1): 16572, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400722

RESUMO

Routinely used typing methods including MLST, rep-PCR and whole genome sequencing (WGS) are time-consuming, costly, and often low throughput. Here, we describe a novel mini-MLST scheme for Eschericha coli as an alternative method for rapid genotyping. Using the proposed mini-MLST scheme, 10,946 existing STs were converted into 1,038 Melting Types (MelTs). To validate the new mini-MLST scheme, in silico analysis was performed on 73,704 strains retrieved from EnteroBase resulting in discriminatory power D = 0.9465 (CI 95% 0.9726-0.9736) for mini-MLST and D = 0.9731 (CI 95% 0.9726-0.9736) for MLST. Moreover, validation on clinical isolates was conducted with a significant concordance between MLST, rep-PCR and WGS. To conclude, the great portability, efficient processing, cost-effectiveness, and high throughput of mini-MLST represents immense benefits, even when accompanied with a slightly lower discriminatory power than other typing methods. This study proved mini-MLST is an ideal method to screen and subgroup large sets of isolates and/or quick strain typing during outbreaks. In addition, our results clearly showed its suitability for prospective surveillance monitoring of emergent and high-risk E. coli clones'.


Assuntos
Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Escherichia coli/genética , Genes Bacterianos , Técnicas de Genotipagem , Tipagem de Sequências Multilocus/métodos , Polimorfismo de Nucleotídeo Único , Composição de Bases , Simulação por Computador , República Tcheca/epidemiologia , Primers do DNA , DNA Bacteriano/química , Surtos de Doenças , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Genoma Bacteriano , Desnaturação de Ácido Nucleico , Reação em Cadeia da Polimerase/métodos , Vigilância da População , Sequências Repetitivas de Ácido Nucleico , Sequenciamento Completo do Genoma
17.
J Clin Microbiol ; 48(9): 3392-4, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20592150

RESUMO

We present a method for rapid and simple detection of clinically relevant mucormycetes of the Mucorales order in cultures and clinical samples. This seminested real-time PCR uses mucormycete-specific primers and is followed by species identification using high-resolution melt (HRM) analysis. The method is highly suitable for routine clinical diagnostics.


Assuntos
DNA Fúngico/genética , Mucorales/classificação , Mucorales/isolamento & purificação , Mucormicose/diagnóstico , Micologia/métodos , Reação em Cadeia da Polimerase/métodos , DNA Fúngico/química , Humanos , Dados de Sequência Molecular , Mucorales/genética , Análise de Sequência de DNA , Temperatura de Transição
18.
Sci Rep ; 10(1): 17963, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087853

RESUMO

Invasive fungal disease (IFD) early diagnosis improves hematological patient survival. Non-culture-based methods may reduce diagnostic time to identify IFD. As complex data on the value of 1,3-ß-D-glucan (BDG) from bronchoalveolar lavage fluid (BALF) compared to serum for the most frequent invasive pulmonary aspergillosis (IPA) diagnosis are scarce, particularly including evaluation of potential factors adversely affecting BDG assay, we provided prospective single-center analysis evaluating 172 episodes of pulmonary infiltrates with BDG detection in BALF and serum samples collected in parallel among hematological patients from 2006 to 2015. Proven and probable IPA were documented in 13.4% of the episodes. Sensitivity (SEN), specificity (SPE), positive and negative predictive value (PPV; NPV), and diagnostic odds ratio (DOR) of the BDG assay using standard (80 pg/ml) cut-off for BALF were: 56.5%; 83.2%; 34.2%; 92.5%, and 6.5, respectively, and for serum were: 56.5%; 82.6%; 33.3%; 92.5%, and 6.2, respectively. The same BDG assay parameters employing a calculated optimal cut-off for BALF (39 pg/ml) were: 78.3%; 72.5%; 30.5%; 95.6%, and 9.5, respectively; and for serum (40 pg/ml) were: 73.9%; 69.1%; 27.0%; 94.5%, and 6.3, respectively. While identifying acceptable SEN, SPE, and DOR, yet low PPV of both BALF and serum BDG assay for IPA diagnosis, neither the combination of both materials nor the new optimal BDG cut-off led to significant test quality improvement. Absolute neutrophil count and aspirated BALF volume with a significant trend affected BDG assay performance. The BDG test did not outperform galactomannan assay.


Assuntos
Biomarcadores/análise , Biomarcadores/sangue , Líquido da Lavagem Broncoalveolar/química , Neoplasias Hematológicas/complicações , Aspergilose Pulmonar Invasiva/complicações , Aspergilose Pulmonar Invasiva/diagnóstico , beta-Glucanas/análise , beta-Glucanas/sangue , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
19.
PLoS One ; 14(8): e0221187, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31408497

RESUMO

Studying bacterial population diversity is important to understand healthcare associated infections' epidemiology and has a significant impact on dealing with multidrug resistant bacterial outbreaks. We characterised the extended-spectrum beta-lactamase producing K. pneumoniae (ESBLp KPN) population in our hospital using mini-MLST. Then we used whole genome sequencing (WGS) to compare selected isolates belonging to the most prevalent melting types (MelTs) and the colonization/infection pair isolates collected from one patient to study the ESBLp KPN population's genetic diversity. A total of 922 ESBLp KPN isolates collected between 7/2016 and 5/2018 were divided into 38 MelTs using mini-MLST with only 6 MelTs forming 82.8% of all isolates. For WGS, 14 isolates from the most prominent MelTs collected in the monitored period and 10 isolates belonging to the same MelTs collected in our hospital in 2014 were randomly selected. Resistome, virulome and ST were MelT specific and stable over time. A maximum of 23 SNV per core genome and 58 SNV per core and accessory genome were found. To determine the SNV relatedness cut-off values, 22 isolates representing colonization/infection pair samples obtained from 11 different patients were analysed by WGS with a maximum of 22 SNV in the core genome and 40 SNV in the core and accessory genome within pairs. The mini-MLST showed its potential for real-time epidemiology in clinical practice. However, for outbreak evaluation in a low diversity bacterial population, mini-MLST should be combined with more sensitive methods like WGS. Our findings showed there were only minimal differences within the core and accessory genome in the low diversity hospital population and gene based SNV analysis does not have enough discriminatory power to differentiate isolate relatedness. Thus, intergenic regions and mobile elements should be incorporated into the analysis scheme to increase discriminatory power.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla , Infecções por Klebsiella/genética , Klebsiella pneumoniae/genética , Tipagem de Sequências Multilocus , Sequenciamento Completo do Genoma , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Infecção Hospitalar/enzimologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/genética , Infecção Hospitalar/microbiologia , DNA Bacteriano/genética , Feminino , Humanos , Lactente , Recém-Nascido , Infecções por Klebsiella/enzimologia , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/isolamento & purificação , Masculino , Pessoa de Meia-Idade , beta-Lactamases/metabolismo
20.
Folia Microbiol (Praha) ; 64(3): 421-428, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30535753

RESUMO

Rapid diagnostics of fungal pneumonia and initiation of appropriate therapy are still challenging. In this study, we used two panfungal assays to test bronchoalveolar lavage fluid (BALF) samples to prove their ability to confirm invasive fungal disease diagnosis and identify causative agents. Two methods targeting different fungal rDNA regions were used, and the obtained PCR products were sequenced directly or after cloning. In total, 106 BALF samples from 104 patients were tested. After sequencing, we obtained 578 sequences. Four hundred thirty-seven sequences were excluded from further analysis due to duplication (n = 335) or similarity with sequences detected in the extraction control sample (n = 102); 141 unique sequences were analyzed. Altogether, 23/141 (16%) of the fungi detected belonged to pathogenic species, and 63/141 (45%) were identified as various yeasts; a variety of environmental or very rare fungal human pathogens represented 29/141 (21%) of the total and 26/141 (18%) were described as uncultured fungus. Panfungal PCR detected fungal species that would be missed by specific methods in only one case (probable cryptococcosis). Panfungal PCR followed by sequencing has limited use for testing BALF samples due to frequent commensal or environmental fungal species pickup.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Fungos/isolamento & purificação , Hospedeiro Imunocomprometido , Infecções Fúngicas Invasivas/diagnóstico , Primers do DNA/genética , DNA Fúngico/genética , DNA Intergênico/genética , Feminino , Fungos/genética , Fungos/patogenicidade , Humanos , Masculino , Técnicas de Diagnóstico Molecular , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Análise de Sequência de DNA
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