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1.
Crit Care ; 28(1): 236, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997712

RESUMO

BACKGROUND: To determine whether a decrease in serum (1,3)-ß-D-glucan (BDG) was associated with reduced mortality and to investigate the performance of BDG downslope in predicting clinical outcome in invasive candidiasis. METHODS: Observational cohort study in ICU patients over a ten-year period (2012-2022) in Italy. Proven invasive candidiasis with at least 2 BDG determinations were considered. RESULTS: In the study population of 103 patients (age 47 [35-62] years, SAPS II score 67 [52-77]) 68 bloodstream and 35 intrabdominal infections were recorded. Serial measurements showed that in 54 patients BDG decreased over time (BDG downslope group) while in 49 did not (N-BDG downslope group). Candida albicans was the pathogen most frequently isolated (61%) followed by C. parapsilosis (17%) and C. glabrata (12%), in absence of any inter-group difference. Invasive candidiasis related mortality was lower in BDG downslope than in N-BDG downslope group (17% vs 53%, p < 0.01). The multivariate Cox regression analysis showed the association of septic shock at infection occurrence and chronic liver disease with invasive candidiasis mortality (HR [95% CI] 3.24 [1.25-8.44] p = 0.02 and 7.27 [2.33-22.66] p < 0.01, respectively) while a BDG downslope was the only predictor of survival (HR [95% CI] 0.19 [0.09-0.43] p < 0.01). The area under the receiver operator characteristic curve for the performance of BDG downslope as predictor of good clinical outcome was 0.74 (p = 0.02) and our model showed that a BDG downslope > 70% predicted survival with both specificity and positive predictive value of 100%. CONCLUSIONS: A decrease in serum BDG was associated with reduced mortality and a steep downslope predicted survival with high specificity in invasive candidiasis.


Assuntos
Candidíase Invasiva , Unidades de Terapia Intensiva , beta-Glucanas , Humanos , Pessoa de Meia-Idade , Masculino , Candidíase Invasiva/sangue , Candidíase Invasiva/mortalidade , Candidíase Invasiva/diagnóstico , Feminino , Unidades de Terapia Intensiva/estatística & dados numéricos , Unidades de Terapia Intensiva/organização & administração , beta-Glucanas/sangue , beta-Glucanas/análise , Prognóstico , Adulto , Estudos de Coortes , Itália/epidemiologia , Biomarcadores/sangue , Biomarcadores/análise , Proteoglicanas/sangue , Proteoglicanas/análise , Valor Preditivo dos Testes
2.
Nature ; 530(7591): 485-9, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26886795

RESUMO

Eukaryotic transcription activators stimulate the expression of specific sets of target genes through recruitment of co-activators such as the RNA polymerase II-interacting Mediator complex. Aberrant function of transcription activators has been implicated in several diseases. However, therapeutic targeting efforts have been hampered by a lack of detailed molecular knowledge of the mechanisms of gene activation by disease-associated transcription activators. We previously identified an activator-targeted three-helix bundle KIX domain in the human MED15 Mediator subunit that is structurally conserved in Gal11/Med15 Mediator subunits in fungi. The Gal11/Med15 KIX domain engages pleiotropic drug resistance transcription factor (Pdr1) orthologues, which are key regulators of the multidrug resistance pathway in Saccharomyces cerevisiae and in the clinically important human pathogen Candida glabrata. The prevalence of C. glabrata is rising, partly owing to its low intrinsic susceptibility to azoles, the most widely used antifungal agent. Drug-resistant clinical isolates of C. glabrata most commonly contain point mutations in Pdr1 that render it constitutively active, suggesting that this transcriptional activation pathway represents a linchpin in C. glabrata multidrug resistance. Here we perform sequential biochemical and in vivo high-throughput screens to identify small-molecule inhibitors of the interaction of the C. glabrata Pdr1 activation domain with the C. glabrata Gal11A KIX domain. The lead compound (iKIX1) inhibits Pdr1-dependent gene activation and re-sensitizes drug-resistant C. glabrata to azole antifungals in vitro and in animal models for disseminated and urinary tract C. glabrata infection. Determining the NMR structure of the C. glabrata Gal11A KIX domain provides a detailed understanding of the molecular mechanism of Pdr1 gene activation and multidrug resistance inhibition by iKIX1. We have demonstrated the feasibility of small-molecule targeting of a transcription factor-binding site in Mediator as a novel therapeutic strategy in fungal infectious disease.


Assuntos
Antifúngicos/farmacologia , Candida glabrata/efeitos dos fármacos , Candida glabrata/metabolismo , Farmacorresistência Fúngica/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Complexo Mediador/metabolismo , Transativadores/metabolismo , Animais , Sítios de Ligação/efeitos dos fármacos , Candida glabrata/genética , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Farmacorresistência Fúngica Múltipla/efeitos dos fármacos , Fluconazol/farmacologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hidrazinas/farmacocinética , Hidrazinas/farmacologia , Cetoconazol/farmacologia , Complexo Mediador/química , Camundongos , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Tioureia/análogos & derivados , Tioureia/farmacocinética , Tioureia/farmacologia , Transativadores/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
3.
Mycoses ; 65(12): 1127-1136, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35842900

RESUMO

BACKGROUND: Onychomycosis (OM) accounts for about 50% of nail disorders in industrialised countries. Essential oils (EOs), aromatic natural compounds, are known for their antimicrobial activity. OBJECTIVE: The aim of this work was to evaluate the antifungal efficacy of seven EOs and a commercial MIX against 10 dermatophytes responsible for OM to select the most effective ones to be included in a preventive or curative formulation based on a green natural nail polish (GNNP). METHODS: Micro-broth dilution tests in line with EUCAST guidelines and olfactory satisfaction test were performed to select the best natural compounds previously analysed by SPME coupled with GC-MS. The same method was used to evaluate the release over time of the active compounds present in the two modified-GNNPs made by adding the best natural compound selected (the C. citratus EO) and the MIX. Furthermore, to evaluate the preventive and curative activity of modified-GNNPs, ex vivo experiments on healthy or colonised nails were performed. RESULTS AND CONCLUSIONS: Data showed that MIX-modified-GNNP had preventive activity as it inhibits the fungal growth by releasing its active ingredients for 7 days, while the OE-modified GNNP acts as a natural drug showing cytocidal activity on nails colonised by dermatophytes, but it requires two weekly applications.


Assuntos
Óleos Voláteis , Onicomicose , Humanos , Onicomicose/tratamento farmacológico , Óleos Voláteis/farmacologia , Óleos Voláteis/uso terapêutico , Polônia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Unhas
4.
Int J Mol Sci ; 23(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35216297

RESUMO

The increasing resistance of fungi to antibiotics is a severe challenge in public health, and newly effective drugs are required. Promising potential medications are lipopeptides, linear antimicrobial peptides (AMPs) conjugated to a lipid tail, usually at the N-terminus. In this paper, we investigated the in vitro and in vivo antifungal activity of three short myristoylated and non-myristoylated peptides derived from a mutant of the AMP Chionodracine. We determined their interaction with anionic and zwitterionic membrane-mimicking vesicles and their structure during this interaction. We then investigated their cytotoxic and hemolytic activity against mammalian cells. Lipidated peptides showed a broad spectrum of activity against a relevant panel of pathogen fungi belonging to Candida spp., including the multidrug-resistant C. auris. The antifungal activity was also observed vs. biofilms of C. albicans, C. tropicalis, and C. auris. Finally, a pilot efficacy study was conducted on the in vivo model consisting of Galleria mellonella larvae. Treatment with the most-promising myristoylated peptide was effective in counteracting the infection from C. auris and C. albicans and the death of the larvae. Therefore, this myristoylated peptide is a potential candidate to develop antifungal agents against human fungal pathogens.


Assuntos
Antifúngicos , Candida , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Biofilmes , Candida albicans , Humanos , Larva , Lipopeptídeos/farmacologia , Mamíferos , Testes de Sensibilidade Microbiana
5.
BMC Infect Dis ; 21(1): 82, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33461505

RESUMO

BACKGROUND: Keratitis due to by filamentous fungi are not easy to diagnose thus causing a delay in correct therapy. There are many descriptions of keratitis due to Candida, Fusarium and Aspergillus genera. Subramaniula genus has only recently been reported to cause human infections and there are few descriptions of eye infections due to this filamentous fungus. Diagnosis of fungal keratitis is usually based on microscopic and cultural techniques of samples obtained by corneal swabbing or scraping. Considering the amount of time required to obtain culture results it is wise to use other diagnostic methods, such as molecular analyses. Therapeutic options against these fungi are limited by low tissue penetration in the eye due to ocular barriers. We describe the first case of S. asteroides human keratitis treated with isavuconazole. CASE PRESENTATION: We describe a rare case of fungal keratitis unresponsive to antimicrobial treatment in a 65-year-old male patient without a history of diabetes or immunological diseases. He reported that the onset of symptoms occurred during a long holiday in Cape Verde Island. Initial treatment with topical antibiotics associated to steroids were ineffective, allowing a slow clinical progression of disease to corneal perforation. On admission in our Hospital, slit-lamp examination of the left eye showed conjunctival congestion and hyperemia, a large inferior corneal ulceration with brown pigment, corneal edema, about 3 mm of hypopyon and irido-lenticular synechiae. The slow clinical progression of the disease to corneal perforation and the aspect of the ulcer were consistent with a mycotic etiology. Molecular methods used on fungal colonies isolated by Sabouraud's dextrose agar cultures allowed the identification of Subramaniula asteroids from corneal scraping. Antimicrobial test showed a good susceptibility of this filamentous fungus to voriconazole and isavuconazole. Moreover, this fungal keratitis was successfully treated with isavuconazole, without side effects, observing a progressive clinical improvement. CONCLUSIONS: Molecular methods may be useful for the identification of filamentous fungal keratitis on scraping samples thus shortening the time of diagnosis. Systemic therapy by isavuconazole could be useful to treat the filamentous fungal keratitis, reducing the possible adverse effects due to the use of voriconazole by systemic administration.


Assuntos
Úlcera da Córnea/diagnóstico , Infecções Oculares Fúngicas/diagnóstico , Sordariales/isolamento & purificação , Idoso , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Úlcera da Córnea/tratamento farmacológico , Úlcera da Córnea/microbiologia , Diagnóstico Diferencial , Infecções Oculares Fúngicas/tratamento farmacológico , Infecções Oculares Fúngicas/microbiologia , Humanos , Masculino , Nitrilas/administração & dosagem , Nitrilas/uso terapêutico , Soluções Oftálmicas , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Triazóis/administração & dosagem , Triazóis/uso terapêutico
6.
Medicina (Kaunas) ; 57(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206911

RESUMO

Background and Objectives: Overtreatment with antifungal drugs is often observed. Antifungal stewardship (AFS) focuses on optimizing the treatment for invasive fungal diseases. The objective of the present study was to evaluate the utility of a post-prescription audit plus beta-D-glucan (BDG) assessment on reducing echinocandin use in persons with suspected invasive candidiasis. Materials and Methods: This is a prospective, pre-post quasi-experimental study of people starting echinocandins for suspected invasive candidiasis. The intervention of the study included review of each echinocandin prescription and discontinuation of treatment if a very low probability of fungal disease or a negative BDG value were found. Pre-intervention data were compared with the intervention phase. The primary outcome of the study was the duration of echinocandin therapy. Secondary outcomes were length of hospital stay and mortality. Results: Ninety-two echinocandin prescriptions were reviewed, 49 (53.3%) in the pre-intervention phase and 43 (46.7%) in the intervention phase. Discontinuation of antifungal therapy was possible in 21 of the 43 patients in the intervention phase (48.8%). The duration of echinocandin therapy was 7.4 (SD 4.7) in the pre-intervention phase, 4.1 days (SD 2.9) in persons undergoing the intervention, and 8.6 (SD 7.3) in persons in whom the intervention was not feasible (p at ANOVA = 0.016). Length of stay and mortality did not differ between pre-intervention and intervention phases. Conclusions: An intervention based on pre-prescription restriction and post-prescription audit when combined with BDG measurement is effective in optimizing antifungal therapy by significantly reducing excessive treatment duration.


Assuntos
Candidíase Invasiva , Equinocandinas , Antifúngicos/uso terapêutico , Candidíase Invasiva/diagnóstico , Candidíase Invasiva/tratamento farmacológico , Equinocandinas/uso terapêutico , Glucanos , Humanos , Prescrições , Estudos Prospectivos
7.
Crit Care ; 24(1): 550, 2020 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-32891170

RESUMO

BACKGROUND: (1,3)-ß-D-Glucan has been widely used in clinical practice for the diagnosis of invasive Candida infections. However, such serum biomarker showed potential to guide antimicrobial therapy in order to reduce the duration of empirical antifungal treatment in critically ill septic patients with suspected invasive candidiasis. METHODS: This was a single-centre, randomized, open-label clinical trial in which critically ill patients were enrolled during the admission to the intensive care unit (ICU). All septic patients who presented invasive Candida infection risk factors and for whom an empirical antifungal therapy was commenced were randomly assigned (1:1) in those stopping antifungal therapy if (1,3)-ß-D-glucan was negative ((1,3)-ß-D-glucan group) or those continuing the antifungal therapy based on clinical rules (control group). Serum 1,3-ß-D-glucan was measured at the enrolment and every 48/72 h over 14 days afterwards. The primary endpoint was the duration of antifungal treatment in the first 30 days after enrolment. RESULTS: We randomized 108 patients into the (1,3)-ß-D-glucan (n = 53) and control (n = 55) groups. Median [IQR] duration of antifungal treatment was 2 days [1-3] in the (1,3)-ß-D-glucan group vs. 10 days [6-13] in the control group (between-group absolute difference in means, 6.29 days [95% CI 3.94-8.65], p < 0.001). Thirty-day mortality was similar (28.3% [(1,3)-ß-D-glucan group] vs. 27.3% [control group], p = 0.92) as well as the overall rate of documented candidiasis (11.3% [(1,3)-ß-D-glucan group] vs. 12.7% [control group], p = 0.94), the length of mechanical ventilation (p = 0.97) and ICU stay (p = 0.23). CONCLUSIONS: In critically ill septic patients admitted to the ICU at risk of invasive candidiasis, a (1,3)-ß-D-glucan-guided strategy could reduce the duration of empirical antifungal therapy. However, the safety of this algorithm needs to be confirmed in future, multicentre clinical trial with a larger population. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03117439 , retrospectively registered on 18 April 2017.


Assuntos
Candidíase Invasiva/tratamento farmacológico , Proteoglicanas/administração & dosagem , Idoso , Antifúngicos/administração & dosagem , Antifúngicos/uso terapêutico , Estado Terminal/terapia , Feminino , Humanos , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/tendências , Masculino , Pessoa de Meia-Idade , Proteoglicanas/uso terapêutico
8.
Adv Exp Med Biol ; 1282: 21-35, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31468360

RESUMO

The clinical challenge on surface engineering of medical devices to prevent microorganisms adhesion and biofilm formation, has become an essential aspect for medical implants. Antibacterial properties of Graphene Oxide (GO) have been demonstrated across a broad spectrum of bacteria, and the different mechanisms of action with which this nanomaterial interacts with the microbial surface have been elucidated in detail. Innovative protective coatings based on graphene film and hydrogel could represent an innovative solution for the prevention of nosocomial pathogens colonization on implantable device. This brief review mainly focuses on the applications of graphene in nanomedicine with a particular deepening on the antibacterial properties of GO and GO-based nanomaterials. In order to evaluate the possible future applications of GO as an anti-biofilm coating material for medical devices, studies on the ability of graphene coated surface to prevent microbial adhesion are also discussed. A concise review on in vitro toxicity and in vivo safety is also presented.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Equipamentos e Provisões/microbiologia , Grafite/farmacologia , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-31061161

RESUMO

We determined the in vitro activity of fenticonazole against 318 vaginitis isolates of Candida and bacterial species and selected 28 isolates for time-kill studies. At concentrations equal to 4× MIC, fenticonazole reached the 99.9% killing endpoint by ∼10 h for Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli and by ∼17 h for Candida albicans and Candida parapsilosis; and at concentrations equal to 8× MIC, by ∼19 and ∼20 h for Candida glabrata and Candida tropicalis, respectively. At concentrations equal to 2× MIC, fenticonazole required ∼20 h to reach the above endpoint against C. albicans in mixed culture with S. aureus, S. agalactiae, or E. coli versus ∼17 h against C. albicans in pure culture. Supra-MICs are achievable in topically treated patients' vaginal surfaces.


Assuntos
Antibacterianos/uso terapêutico , Antifúngicos/uso terapêutico , Bactérias/efeitos dos fármacos , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Imidazóis/uso terapêutico , Vaginose Bacteriana/tratamento farmacológico , Feminino , Humanos , Testes de Sensibilidade Microbiana/métodos
10.
BMC Infect Dis ; 19(1): 215, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832598

RESUMO

BACKGROUND: Central Line-Associated BloodStream Infections (CLABSIs) are emerging challenge in Respiratory semi-Intensive Care Units (RICUs). We evaluated efficacy of educational interventions on rate of CLABSIs and effects of port protector as adjuvant tool. METHODS: Study lasted 18 months (9 months of observation and 9 of intervention). We enrolled patients with central venous catheter (CVC): 1) placed during hospitalization in RICU; 2) already placed without signs of systemic inflammatory response syndrome (SIRS) within 48 h after the admission; 3) already placed without evidence of microbiologic contamination of blood cultures. During interventional period we randomized patients into two groups: 1) educational intervention (Group 1) and 2) educational intervention plus port protector (Group 2). We focused on CVC-related sepsis as primary outcome. Secondary outcomes were the rate of CVC colonization and CVC contamination. RESULTS: Eighty seven CVCs were included during observational period. CLABSIs rate was 8.4/1000 [10 sepsis (9 CLABSIs)]. We observed 17 CVC colonizations and 6 contaminations. Forty six CVCs were included during interventional period. CLABSIs rate was 1.4/1000. 21/46 CVCs were included into Group 2, in which no CLABSIs or contaminations were reported, while 2 CVC colonizations were found. CONCLUSIONS: Our study clearly shows that both kinds of interventions significantly reduce the rate of CLABSIs. In particular, the use of port protector combined to educational interventions gave zero CLABSIs rate. TRIAL REGISTRATION: NCT03486093 [ ClinicalTrials.gov Identifier], retrospectively registered.


Assuntos
Infecções Relacionadas a Cateter/diagnóstico , Cateterismo Venoso Central/métodos , Idoso , Idoso de 80 Anos ou mais , Hemocultura , Infecções Relacionadas a Cateter/complicações , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Risco , Sepse/diagnóstico , Sepse/etiologia
11.
Biochim Biophys Acta ; 1860(6): 1089-97, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26922830

RESUMO

BACKGROUND: Fungal infections develop in pulmonary chronic inflammatory diseases such as asthma, Chronic Obstructive Pulmonary Disease (COPD) and Cystic Fibrosis (CF). The available antifungal drugs may fail to eradicate fungal pathogens, that can invade the lungs and vessels and spread by systemic circulation taking advantage of defective lung immunity. An increased rate of sphingolipid de novo synthesis, leading to ceramide accumulation, was demonstrated in CF and COPD inflamed lungs. The inhibitor of sphingolipid synthesis myriocin reduces inflammation and ameliorates the response against bacterial airway infection in CF mice. Myriocin also inhibits sphingolipid synthesis in fungi and exerts a powerful fungistatic effect. METHODS: We treated Aspergillus fumigatus infected airway epithelial cells with myriocin and we administered myriocin-loaded nanocarriers to A. fumigatus infected mice lung. RESULTS: We demonstrate here that de novo synthesized ceramide mediates the inflammatory response induced by A. fumigatus infection in airway epithelia. CF epithelial cells are chronically inflamed and defective in killing internalized conidia. Myriocin treatment reduced ceramide increase and inflammatory mediator release whereas it upregulated HO1 and NOD2, allowing the recovery of a functional killing of conidia in these cells. Myriocin-loaded nanocarriers, intratracheally administered to mice, significantly reduced both the inflammatory response induced by A. fumigatus pulmonary challenge and fungal lung invasion. CONCLUSIONS: We conclude that inhibition of sphingolipid synthesis can be envisaged as a dual anti-inflammatory and anti-fungal therapy in patients suffering from chronic lung inflammation with compromised immunity. GENERAL SIGNIFICANCE: Myriocin represents a powerful agent for inflammatory diseases and fungal infection.


Assuntos
Anti-Inflamatórios/farmacologia , Antifúngicos/farmacologia , Aspergillus fumigatus , Ceramidas/antagonistas & inibidores , Ácidos Graxos Monoinsaturados/farmacologia , Aspergilose Pulmonar/tratamento farmacológico , Animais , Antifúngicos/uso terapêutico , Linhagem Celular , Ceramidas/biossíntese , Ácidos Graxos Monoinsaturados/uso terapêutico , Humanos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Aspergilose Pulmonar/patologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-28416538

RESUMO

We tested 59 common and 27 uncommon Aspergillus species isolates for susceptibility to the mold-active azole antifungal agents itraconazole, voriconazole, and posaconazole using the Sensititre method. The overall essential agreement with the CLSI reference method was 96.5% for itraconazole and posaconazole and was 100% for voriconazole. By the Sensititre method as well as the CLSI reference method, all of 10 A. fumigatus isolates with a cyp51 mutant genotype were classified as being non-wild-type isolates (MIC > epidemiological cutoff value [ECV]) with respect to triazole susceptibility.


Assuntos
Antifúngicos/farmacologia , Aspergilose/tratamento farmacológico , Aspergillus/efeitos dos fármacos , Itraconazol/farmacologia , Triazóis/farmacologia , Voriconazol/farmacologia , Aspergilose/microbiologia , Aspergillus/classificação , Aspergillus/isolamento & purificação , Farmacorresistência Fúngica/genética , Testes de Sensibilidade Microbiana , Esterol 14-Desmetilase/genética
14.
Antimicrob Agents Chemother ; 59(7): 3944-55, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25896705

RESUMO

Sensititre YeastOne (SYO) is an affordable alternative to the Clinical and Laboratory Standards Institute (CLSI) reference method for antifungal susceptibility testing. In this study, the MICs of yeast isolates from 1,214 bloodstream infection episodes, generated by SYO during hospital laboratory activity (January 2005 to December 2013), were reanalyzed using current CLSI clinical breakpoints/epidemiological cutoff values to assign susceptibility (or the wild-type [WT] phenotype) to systemic antifungal agents. Excluding Candida albicans (57.4% of all isolates [n = 1,250]), the most predominant species were Candida parapsilosis complex (20.9%), Candida tropicalis (8.2%), Candida glabrata (6.4%), Candida guilliermondii (1.6%), and Candida krusei (1.3%). Among the non-Candida species (1.9%), 7 were Cryptococcus neoformans and 17 were other species, mainly Rhodotorula species. Over 97% of Candida isolates were susceptible (WT phenotype) to amphotericin B and flucytosine. Rates of susceptibility (WT phenotype) to fluconazole, itraconazole, and voriconazole were 98.7% in C. albicans, 92.3% in the C. parapsilosis complex, 96.1% in C. tropicalis, 92.5% in C. glabrata, 100% in C. guilliermondii, and 100% (excluding fluconazole) in C. krusei. The fluconazole-resistant isolates consisted of 6 C. parapsilosis complex isolates, 3 C. glabrata isolates, 2 C. albicans isolates, 2 C. tropicalis isolates, and 1 Candida lusitaniae isolate. Of the non-Candida isolates, 2 C. neoformans isolates had the non-WT phenotype for susceptibility to fluconazole, whereas Rhodotorula isolates had elevated azole MICs. Overall, 99.7% to 99.8% of Candida isolates were susceptible (WT phenotype) to echinocandins, but 3 isolates were nonsusceptible (either intermediate or resistant) to caspofungin (C. albicans, C. guilliermondii, and C. krusei), anidulafungin (C. albicans and C. guilliermondii), and micafungin (C. albicans). However, when the intrinsically resistant non-Candida isolates were included, the rate of echinocandin nonsusceptibility reached 1.8%. In summary, the SYO method proved to be able to detect yeast species showing antifungal resistance or reduced susceptibility.


Assuntos
Antifúngicos/farmacologia , Micoses/microbiologia , Leveduras/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Infecção Hospitalar/microbiologia , Farmacorresistência Fúngica , Feminino , Hospitais de Ensino , Humanos , Itália , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade
15.
J Clin Microbiol ; 52(5): 1453-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24554755

RESUMO

In recent studies evaluating the usefulness of the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS)-based identification of yeasts for the routine diagnosis of fungal infections, preanalytical sample processing has emerged as a critical step for reliable MALDI-TOF MS outcomes, especially when the Bruker Daltonics Biotyper software was used. In addition, inadequate results often occurred due to discrepancies between the methods used for clinical testing and database construction. Therefore, we created an in-house MALDI-TOF MS library using the spectra from 156 reference and clinical yeast isolates (48 species in 11 genera), which were generated with a fast sample preparation procedure. After a retrospective validation study, our database was evaluated on 4,232 yeasts routinely isolated during a 6-month period and fast prepared for MALDI-TOF MS analysis. Thus, 4,209 (99.5%) of the isolates were successfully identified to the species level (with scores of ≥2.0), with 1,676 (39.6%) having scores of >2.3. For the remaining 23 (0.5%) isolates, no reliable identification (with scores of <1.7) was obtained. Interestingly, these isolates were almost always from species uniquely represented or not included in the database. As the MALDI-TOF MS results were, except for 23 isolates, validated without additional phenotypic or molecular tests, our proposed strategy can enhance the rapidity and accuracy of MALDI-TOF MS in identifying medically important yeast species. However, while continuous updating of our database will be necessary to enrich it with more strains/species of new and emerging yeasts, the present in-house MALDI-TOF MS library can be made publicly available for future multicenter studies.


Assuntos
Leveduras/química , Leveduras/isolamento & purificação , Fracionamento Químico/métodos , Bases de Dados Factuais , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
18.
PLoS Pathog ; 8(8): e1002834, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22876178

RESUMO

Oxidative stress serves as an important host/environmental signal that triggers a wide range of responses in microorganisms. Here, we identified an oxidative stress sensor and response regulator in the important multidrug-resistant nosocomial pathogen Enterococcus faecium belonging to the MarR family and called AsrR (antibiotic and stress response regulator). The AsrR regulator used cysteine oxidation to sense the hydrogen peroxide which results in its dissociation to promoter DNA. Transcriptome analysis showed that the AsrR regulon was composed of 181 genes, including representing functionally diverse groups involved in pathogenesis, antibiotic and antimicrobial peptide resistance, oxidative stress, and adaptive responses. Consistent with the upregulated expression of the pbp5 gene, encoding a low-affinity penicillin-binding protein, the asrR null mutant was found to be more resistant to ß-lactam antibiotics. Deletion of asrR markedly decreased the bactericidal activity of ampicillin and vancomycin, which are both commonly used to treat infections due to enterococci, and also led to over-expression of two major adhesins, acm and ecbA, which resulted in enhanced in vitro adhesion to human intestinal cells. Additional pathogenic traits were also reinforced in the asrR null mutant including greater capacity than the parental strain to form biofilm in vitro and greater persistance in Galleria mellonella colonization and mouse systemic infection models. Despite overexpression of oxidative stress-response genes, deletion of asrR was associated with a decreased oxidative stress resistance in vitro, which correlated with a reduced resistance to phagocytic killing by murine macrophages. Interestingly, both strains showed similar amounts of intracellular reactive oxygen species. Finally, we observed a mutator phenotype and enhanced DNA transfer frequencies in the asrR deleted strain. These data indicate that AsrR plays a major role in antimicrobial resistance and adaptation for survival within the host, thereby contributes importantly to the opportunistic traits of E. faecium.


Assuntos
Proteínas de Bactérias/metabolismo , Enterococcus faecium/patogenicidade , Infecções por Bactérias Gram-Positivas/metabolismo , Fatores de Transcrição/metabolismo , Resistência beta-Lactâmica , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Enterococcus faecium/genética , Enterococcus faecium/metabolismo , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/genética , Humanos , Peróxido de Hidrogênio/farmacologia , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oxidantes/farmacologia , Oxirredução/efeitos dos fármacos , Característica Quantitativa Herdável , Fatores de Transcrição/genética , beta-Lactamas/farmacologia
19.
BMC Infect Dis ; 14: 634, 2014 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-25480675

RESUMO

BACKGROUND: Mathematical or statistical tools are capable to provide a valid help to improve surveillance systems for healthcare and non-healthcare-associated bacterial infections. The aim of this work is to evaluate the time-varying auto-adaptive (TVA) algorithm-based use of clinical microbiology laboratory database to forecast medically important drug-resistant bacterial infections. METHODS: Using TVA algorithm, six distinct time series were modelled, each one representing the number of episodes per single 'ESKAPE' (E nterococcus faecium, S taphylococcus aureus, K lebsiella pneumoniae, A cinetobacter baumannii, P seudomonas aeruginosa and E nterobacter species) infecting pathogen, that had occurred monthly between 2002 and 2011 calendar years at the Università Cattolica del Sacro Cuore general hospital. RESULTS: Monthly moving averaged numbers of observed and forecasted ESKAPE infectious episodes were found to show a complete overlapping of their respective smoothed time series curves. Overall good forecast accuracy was observed, with percentages ranging from 82.14% for E. faecium infections to 90.36% for S. aureus infections. CONCLUSIONS: Our approach may regularly provide physicians with forecasted bacterial infection rates to alert them about the spread of antibiotic-resistant bacterial species, especially when clinical microbiological results of patients' specimens are delayed.


Assuntos
Algoritmos , Infecções Bacterianas/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Farmacorresistência Bacteriana , Feminino , Previsões/métodos , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Vigilância da População , Staphylococcus aureus , Fatores de Tempo
20.
Sci Rep ; 14(1): 3344, 2024 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336904

RESUMO

Endoscopic Retrograde Cholangio-Pancreatography (ERCP) with biliary stenting is a minimally invasive medical procedure employed to address both malignant and benign obstructions within the biliary tract. Benign biliary strictures (BBSs), typically arising from surgical interventions such as liver transplants and cholecystectomy, as well as chronic inflammatory conditions, present a common clinical challenge. The current gold standard for treating BBSs involves the periodic insertion of plastic stents at intervals of 3-4 months, spanning a course of approximately one year. Unfortunately, stent occlusion emerges as a prevalent issue within this treatment paradigm, leading to the recurrence of symptoms and necessitating repeated ERCPs. In response to this clinical concern, we initiated a pilot study, delving into the microbial composition present in bile and on the inner surfaces of plastic stents. This investigation encompassed 22 patients afflicted by BBSs who had previously undergone ERCP with plastic stent placement. Our preliminary findings offered promising insights into the microbial culprits behind stent occlusion, with Enterobacter and Lactobacillus spp. standing out as prominent bacterial species known for their biofilm-forming tendencies on stent surfaces. These revelations hold promise for potential interventions, including targeted antimicrobial therapies aimed at curtailing bacterial growth on stents and the development of advanced stent materials boasting anti-biofilm properties.


Assuntos
Sistema Biliar , Colestase , Humanos , Bile , Projetos Piloto , Resultado do Tratamento , Colestase/cirurgia , Colangiopancreatografia Retrógrada Endoscópica/métodos , Stents , Estudos Retrospectivos
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