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1.
Pathogens ; 13(2)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38392866

RESUMEN

Antifungal therapy, especially with the azoles, could promote the incidence of less susceptible isolates of Cryptococcus neoformans and C. gattii species complexes (SC), mostly in developing countries. Given that these species affect mostly the immunocompromised host, the infections are severe and difficult to treat. This review encompasses the following topics: 1. infecting species and their virulence, 2. treatment, 3. antifungal susceptibility methods and available categorical endpoints, 4. genetic mechanisms of resistance, 5. clinical resistance, 6. fluconazole minimal inhibitory concentrations (MICs), clinical outcome, 7. environmental influences, and 8. the relevance of host factors, including pharmacokinetic/pharmacodynamic (PK/PD) parameters, in predicting the clinical outcome to therapy. As of now, epidemiologic cutoff endpoints (ECVs/ECOFFs) are the most reliable antifungal resistance detectors for these species, as only one clinical breakpoint (amphotericin B and C. neoformans VNI) is available.

2.
Med Mycol ; 61(4)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36931889

RESUMEN

Candida haemulonii complex species can be multidrug-resistant and cause infections such as candidemia. This study determined the genetic relationship between isolates from Brazil and the United States through whole-genome sequencing and performed antifungal susceptibility testing to investigate drug resistance. Contrary to what is widely described, most isolates were susceptible to azoles. However, an atypical susceptibility profile was found in 50% of Candida pseudohaemulonii strains, including resistance to the three echinocandins. Isolates from both countries formed distinct clusters with wide genetic diversity. Isolates from three hospitals in Brazil were clonal and involved in candidemia cases, pointing to the importance of improving hospital infection control measures and molecular identification.


Candida haemulonii complex species is worldwide distributed, and this study aimed to evaluate the resistance to antifungal drugs in cases from Brazil and the United States, and also compare their genetic relationships. A total of 50 strains were studied; most of them from Brazil were from cases of bloodstream infections, while the strains from the United States came from cases of wounds and may be associated with diabetic patients. The vast majority of strains were resistant to amphotericin B, one of the most effective drugs, and susceptible to fluconazole. In addition, 50% of C. pseudohaemulonii strains were resistant to echinocandins. The strains from Brazil and the United States had no genetic relationship and formed two distinct groups. In three Brazilian hospitals, strains were clonal, indicating an intra-hospital transmission. Our findings contribute to guiding therapy in bloodstream fungal infections caused by C. haemulonii species and alerting for nosocomial transmission of this yeast complex species.


Asunto(s)
Antifúngicos , Candidemia , Estados Unidos , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candidemia/microbiología , Candidemia/veterinaria , Candida , Brasil/epidemiología , Variación Genética , Pruebas de Sensibilidad Microbiana/veterinaria , Farmacorresistencia Fúngica/genética
3.
Med Mycol ; 61(3)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36893795

RESUMEN

Military women on active duty are exposed to constant physical and mental demands, which may predispose them to some infection risks, including vulvovaginal candidiasis (VVC), a pathology considered a global public health problem. To monitor the prevalent and emerging pathogens in VVC, this study aimed to evaluate the distribution of yeast species and their in vitro antifungal susceptibility profile. We studied 104 vaginal yeast specimens obtained during routine clinical examinations. The population was attended at the Medical Center of the Military Police, São Paulo, Brazil, and was divided into two groups: infected patients (VVC) and colonised patients. Species were identified by phenotypic and proteomic methods (MALDI-TOF MS) and susceptibility to eight antifungal drugs, including azoles, polyenes, and echinocandins, was determined using microdilution broth. Candida albicans stricto sensu was found to be the most frequently isolated species (55%), but we observed a considerable rate of other Candida species isolates (30%), including Candida orthopsilosis stricto sensu only in the infected group. There were also other rare genera such as Rhodotorula, Yarrowia, and Trichosporon (15%), of which Rhodotorula mucilaginosa was the most prevalent in both groups. Fluconazole and voriconazole had the highest activity against all species in both groups. Candida parapsilosis was the most susceptible species, except for amphotericin-B in the infected group. Of note, we observed unusual resistance in C. albicans. Our results have allowed us to compile an epidemiological database on the etiology of VVC to support the empirical treatment and improve the health care of military women.


Vulvovaginal candidiasis (VVC) is an infection caused by fungi, mainly Candida albicans. Our results show that fungi other than C. albicans can cause VVC. So, our findings may help to choose the most appropriate treatment, as some may be resistant, to improve the quality of life of military women.


Asunto(s)
Antifúngicos , Candidiasis Vulvovaginal , Femenino , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candidiasis Vulvovaginal/microbiología , Candidiasis Vulvovaginal/veterinaria , Estudios Transversales , Proteómica , Brasil/epidemiología , Candida albicans , Candida parapsilosis , Pruebas de Sensibilidad Microbiana/veterinaria , Farmacorresistencia Fúngica
4.
Med Mycol ; 61(3)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36807459

RESUMEN

Trichosporonosis corresponds to a systemic fungal disease that leads to high mortality rates and is frequently associated with medical devices. It affects immunosuppressed patients in particular and is strongly linked to acquired human immunodeficiency, organ and tissue transplants, and malignant hematologic diseases such as leukemia and lymphomas. Trichosporon infections have been increasingly reported worldwide; however, little information is available either about their characteristics or the causative microorganism. Thus, the aims of the present study were: to investigate 59 yeasts of the genus Trichosporon by verifying the biofilm formation capacity of isolates; to analyze the susceptibility patterns of planktonic cells against the antifungals fluconazole, itraconazole, amphotericin-B, voriconazole, and caspofungin by comparing European Committee for Antimicrobial Susceptibility Testing (EUCAST) broth microdilution technique with the commercial method Etest; and to assess the susceptibility patterns of biofilm cells (sessile) against the same antifungals through broth microdilution. The ability to form biofilm on the surface of polystyrene plates was noted for all isolates, and 54.3% of samples were considered strong producers. Comparison between the antifungal susceptibility techniques evidenced that Etest showed higher and discordant minimum inhibitory concentrations (MICs) from those obtained by the microdilution method, especially for fluconazole, itraconazole, and caspofungin. Considering the susceptibility of biofilms, most species had high MIC50 and MIC90 against the tested antifungals, showing 4-to-66-fold higher concentrations for amphotericin B and 2-to-33-fold greater concentrations for caspofungin. These results highlight the importance of further studies with Trichosporon spp. for comparison between laboratory findings and in vivo response, considering both the susceptibility tests and the behavior of biofilm cells against drugs.


This study investigated 59 isolates of the medically important yeast Trichosporon in relation to their ability to form biofilms and the susceptibility of biofilms to antifungal agents. All isolates were able to produce biofilms and biofilms showed lower antifungal susceptibility.


Asunto(s)
Trichosporon , Tricosporonosis , Humanos , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Fluconazol/farmacología , Caspofungina , Itraconazol , Anfotericina B/farmacología , Tricosporonosis/microbiología , Tricosporonosis/veterinaria , Biopelículas , Pruebas de Sensibilidad Microbiana/veterinaria
5.
Pharmaceutics ; 14(10)2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36297597

RESUMEN

Aspergillosis is an invasive fungal disease associated with high mortality. Antifungal susceptibility testing (AFST) is receiving increasing consideration for managing patients, as well as for surveilling emerging drug resistance, despite having time-consuming and technically complex reference methodologies. The Sensititre YeastOne (SYO) and Etest methods are widely utilized for yeasts but have not been extensively evaluated for Aspergillus isolates. We obtained Posaconazole (POS), Voriconazole (VCZ), Itraconazole (ITC), Amphotericin B (AMB), Caspofungin (CAS), and Anidulafungin (AND) minimum inhibitory concentrations (MICs) for both the Etest (n = 330) and SYO (n = 339) methods for 106 sequenced clinical strains. For 84 A. fumigatus, we analyzed the performance of both commercial methods in comparison with the CLSI-AFST, using available cutoff values. An excellent correlation could be demonstrated for Etest-AMB and Etest-VCZ (p < 0.01). SYO-MICs of AMB, VCZ, and POS resulted in excellent essential agreement (>93%), and >80% for AMB, VCZ, and ITC Etest-MICs. High categoric agreement was found for AMB, ITC, and CAS Etest-MICs (>85%) and AMB SYO-MICs (>90%). The considerable number of major/very major errors found using Etest and SYO, possibly related to the proposed cutoffs and associated with the less time-consuming processes, support the need for the improvement of commercial methods for Aspergillus strains.

6.
Artículo en Inglés | MEDLINE | ID: mdl-36118844

RESUMEN

Background: Cryptoccocal meningitis continues to present high incidence among AIDS patients. The treatment of choice is the synergistic combination of flucytosine (5-FC) with amphotericin B deoxycholate (AmBd) or its lipid formulations. However, 5-FC is unavailable in many countries and AmB demands hospitalization. The combination of AmB with the fungistatic fluconazole (FLC) or the use of high FLC daily doses alone became the choice. Nonetheless, sterilization of cerebrospinal fluid is delayed with FLC monotherapy, mainly with high fungal burden. These findings suggest the search for new antifungal compounds, such as liriodenine. Methods: Liriodenine antifungal activity was evaluated by three procedures: determining the minimum inhibitory concentration (MIC) on 30 strains of the Cryptococcus neoformans (C. neoformans) complex and 30 of the Cryptococcus gattii (C. gattii) complex, using EUCAST methodology and amphotericin B deoxycholate as control; performing the time-kill methodology in two strains of the C. neoformans complex and one of the C. gattii complex; and injury to cryptococcal cells, evaluated by transmission electron microscopy (TEM). Liriodenine absorption and safety at 0.75 and 1.50 mg.kg-1 doses were evaluated in BALB/c mice. Results: Liriodenine MICs ranged from 3.9 to 62.5 µg.mL-1 for both species complexes, with no differences between them. Time-kill methodology confirmed its concentration-dependent fungicidal effect, killing all the strains below the limit of detection (33 CFU.mL-1) at the highest liriodenine concentration (32-fold MIC), with predominant activity during the first 48 hours. Liriodenine induced severe Cryptococcus alterations - cytoplasm with intense rarefaction and/or degradation, injury of organelles, and presence of vacuoles. Liriodenine was better absorbed at lower doses, with no histopathological alterations on the digestive tract. Conclusion: The fungicidal activity confirmed by time-kill methodology, the intense Cryptococcus injury observed by TEM, the absorption after gavage administration, and the safety at the tested doses indicate that the liriodenine molecule is a promising drug lead for development of anticryptococcal agents.

7.
Mycoses ; 65(12): 1146-1158, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35869803

RESUMEN

INTRODUCTION: Chromoblastomycosis is a disease caused by melanized fungi, primarily belonging to the genera Fonsecaea and Cladophialophora, mainly affecting individuals who are occupationally exposed to soil and plant products. This research aimed to determine the clinical, epidemiological and laboratory characteristics of chromoblastomycosis in the state of Mato Grosso, Brazil. MATERIALS AND METHODS: Patients diagnosed with chromoblastomycosis treated at the Júlio Müller University Hospital, Cuiabá, Brazil, from January 2015 to December 2020, whose isolates were preserved in the Research Laboratory of the Faculty of Medicine of the Federal University of Mato Grosso. Isolates were identified by partly sequencing the Internal Transcribed Spacer (ITS) and ß-tubulin (BT2) loci. AFLP fingerprinting was used to explore the genetic diversity. Susceptibility to itraconazole, voriconazole, 5-fluorocytosine, terbinafine and amphotericin B was determined by the broth microdilution technique. RESULTS: Ten patients were included, nine were male (mean age = 64.1 years). Mean disease duration was 8.6 years. Lesions were mainly observed in the lower limbs. Predominant clinical forms were verrucous and scarring. Systemic arterial hypertension and type II diabetes mellitus were the predominant comorbidities. Leprosy was the main concomitant infectious disease. Fonsecaea pedrosoi was the unique aetiological agent identified with moderate genetic diversity (H = 0.3934-0.4527; PIC = 0.3160-0.3502). Antifungal agents with the highest activity were terbinafine, voriconazole and itraconazole. CONCLUSION: Chromoblastomycosis is affecting the poor population in rural and urban areas, mainly related to agricultural activities, with F. pedrosoi being the dominant aetiologic agent. All isolates had low MICs for itraconazole, voriconazole and terbinafine, confirming their importance as therapeutic alternatives for chromoblastomycosis.


Asunto(s)
Cromoblastomicosis , Diabetes Mellitus Tipo 2 , Humanos , Persona de Mediana Edad , Cromoblastomicosis/tratamiento farmacológico , Cromoblastomicosis/epidemiología , Cromoblastomicosis/microbiología , Itraconazol/farmacología , Itraconazol/uso terapéutico , Terbinafina/uso terapéutico , Voriconazol/uso terapéutico , Epidemiología Molecular , Brasil/epidemiología , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Antifúngicos/farmacología , Antifúngicos/uso terapéutico
9.
J Water Health ; 19(5): 724-735, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34665766

RESUMEN

The aim of this study was to investigate the occurrence of fungi in dialysis water and dialysate, in addition to evaluating the susceptibility to antifungals and the biofilm production capacity of isolated microorganisms. The samples were collected in three hemodialysis units in Bauru (Brazil), every 15 days (July 2017-June 2018) at post-reverse osmosis, reuse, and dialysate points. The fungi were isolated by spread plate on Sabouraud dextrose agar. Filamentous fungi were phenotypically identified and yeasts were subjected to molecular evaluation of the ITS region. Susceptibility test to antifungals was carried out by the broth microdilution method and biofilm production capacity was evaluated in microtiter plates using crystal violet staining. Fungi were isolated in 52/216 (24.1%) samples, with an average count of 16.3 (10-40) CFU/mL. Overall, 61 microorganisms were identified, with 54 (88.5%) filamentous fungi and 7 (11.5%) yeasts. The main genera included were Penicillium, Cladosporium, Scedosporium, Rhinocladiella, Fusarium, and Emmonsia. Most isolates showed high values of minimum inhibitory concentration for 5-flucytosine and fluconazole and 35/45 (77.8%) isolates were classified as strong producers of biofilm. In order to increase the safety of the dialysis process, the adoption of control measures and monitoring of fungi in hemodialysis fluids is suggested.


Asunto(s)
Antifúngicos , Soluciones para Diálisis , Antifúngicos/farmacología , Biopelículas , Diálisis , Hongos , Pruebas de Sensibilidad Microbiana , Diálisis Renal , Agua
10.
Journal of water & health ; 00(0): 1-12, 2021. tab, graf
Artículo en Inglés | CONASS, Sec. Est. Saúde SP, SESSP-IALPROD, Sec. Est. Saúde SP | ID: biblio-1292361

RESUMEN

The aim of this study was to investigate the occurrence of fungi in dialysis water and dialysate, in addition to evaluating the susceptibility to antifungals and the biofilm production capacity of isolated microorganisms. The samples were collected in three hemodialysis units in Bauru (Brazil), every 15 days (July 2017­June 2018) at post-reverse osmosis, reuse, and dialysate points. The fungi were isolated by spread plate on Sabouraud dextrose agar. Filamentous fungi were phenotypically identified and yeasts were subjected to molecular evaluation of the ITS region. Susceptibility test to antifungals was carried out by the broth microdilution method and biofilm production capacity was evaluated in microtiter plates using crystal violet staining. Fungi were isolated in 52/216 (24.1%) samples, with an average count of 16.3 (10­40) CFU/ mL. Overall, 61 microorganisms were identified, with 54 (88.5%) filamentous fungi and 7 (11.5%) yeasts. The main genera included were Penicillium, Cladosporium, Scedosporium, Rhinocladiella, Fusarium, and Emmonsia. Most isolates showed high values of minimum inhibitory concentration for 5-flucytosine and fluconazole and 35/45 (77.8%) isolates were classified as strong producers of biofilm. In order to increase the safety of the dialysis process, the adoption of control measures and monitoring of fungi in hemodialysis fluids is suggested.


Asunto(s)
Chrysosporium , Soluciones para Diálisis , Diálisis , Antifúngicos , Diálisis Renal , Biopelículas
12.
J Clin Microbiol ; 57(1)2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30429250

RESUMEN

Cryptococcus neoformans and Cryptococcus gattii are the main pathogenic species of invasive cryptococcosis among the Cryptococcus species. Taxonomic studies have shown that these two taxa have different genotypes or molecular types with biological and ecoepidemiological peculiarities. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been proposed as an alternative method for labor-intensive methods for C. neoformans and C. gattii genotype differentiation. However, Vitek MS, one of the commercial MALDI-TOF MS instruments, has not been yet been evaluated for this purpose. Thus, we constructed an in-house database with reference strains belonging to the different C. neoformans (VNI, VNII, VNIII, and VNIV) and C. gattii (VGI, VGII, VGIII, and VGIV) major molecular types by using the software Saramis Premium (bioMérieux, Marcy-l'Etoile, France). Then, this new database was evaluated for discrimination of the different genotypes. Our in-house database provided correct identification for all C. neoformans and C. gattii genotypes; however, due to the intergenotypic mass spectral similarities, a careful postanalytic evaluation is necessary to provide correct genotype identification.


Asunto(s)
Criptococosis/microbiología , Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Técnicas de Tipificación Micológica/métodos , Técnicas de Tipificación Micológica/normas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/normas , Cryptococcus gattii/química , Cryptococcus gattii/clasificación , Cryptococcus gattii/aislamiento & purificación , Cryptococcus neoformans/química , Cryptococcus neoformans/clasificación , Cryptococcus neoformans/aislamiento & purificación , Bases de Datos Genéticas , Genotipo , Humanos
13.
BMC Vet Res ; 14(1): 229, 2018 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-30124171

RESUMEN

BACKGROUND: The incidence of visceral leishmaniasis (VL), one of the most important neglected diseases worldwide, is increasing in Brazil. The objectives of this study were to determine the canine VL (CanL) seroprevalence in an urban area of Araçatuba municipality and to evaluate its relationship with the characteristics of dogs and their owners. RESULTS: The CanL seroprevalence in the study area was 0.081 (95% credible interval [CI]: 0.068-0.096). The following covariates/categories were positively associated with the occurrence of a seropositive dog: more than 10 dogs that had lived in the house (odds ratio [OR] = 2.36; 95% CI: 1.03-5.43) (baseline: 0-10 dogs); house with dogs that previously died of VL (OR = 4.85; 95% CI: 2.65-8.86) or died of causes other than old age (OR = 2.26; 95% CI: 1.12-4.46) (baseline: natural or no deaths); dogs that spent the day in a sheltered backyard (OR = 2.14; 95% CI: 1.05-4.40); dogs that spent the day in an unsheltered backyard or the street (OR = 2.67; 95% CI: 1.28-5.57) (baseline: inside home). Spatial dependence among observations occurred within about 45.7 m. CONCLUSIONS: The number of dogs that had lived in the house, previous deaths by VL or other cause, and the place the dog stayed during the day were associated with the occurrence of a VL seropositive dog. The short-distance spatial dependence could be related to the vector characteristics, producing a local neighbourhood VL transmission pattern. The geostatistical approach in a Bayesian context using integrated nested Laplace approximation (INLA) allowed to identify the covariates associated with VL, including its spatially dependent transmission pattern.


Asunto(s)
Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Leishmaniasis Visceral/veterinaria , Análisis Espacial , Animales , Teorema de Bayes , Brasil/epidemiología , Estudios Transversales , Perros , Femenino , Incidencia , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/mortalidad , Masculino , Características de la Residencia , Estudios Seroepidemiológicos
14.
Vet Parasitol Reg Stud Reports ; 12: 13-16, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-31014800

RESUMEN

Visceral leishmaniosis (VL) is a public health problem and its occurrence depends primarily on the presence of the vector and susceptible hosts; in the urban environment, the dog is the main reservoir. This study aimed to analyze the distribution of canine visceral leishmaniosis (CVL) and factors associated with it in an urban area endemic for VL. Analysis of the variables was based on 2755 epidemiological records of dogs positive and negative for CVL over a three-year period (2009, 2010 and 2011). A dog was considered positive when it presented amastigotes in the cytological examination of lymph node biopsy and/or was seropositive by immunoenzymatic and indirect immunofluorescence assays. CVL positive dogs were observed throughout the town, but significant differences were observed between the sectors analyzed (P<0.0001), with two sectors showing higher positivity. CVL prevalence was 35.9% and was significantly associated with age and breed (P<0.0001). Concerning symptoms, 44.3% of symptomatic dogs were positive for LV (P<0.0001) in an urban area endemic for this zoonosis.


Asunto(s)
Reservorios de Enfermedades/veterinaria , Enfermedades de los Perros/diagnóstico , Leishmaniasis Visceral/diagnóstico , Animales , Brasil/epidemiología , Reservorios de Enfermedades/parasitología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Perros , Enfermedades Endémicas/estadística & datos numéricos , Femenino , Leishmaniasis Visceral/epidemiología , Masculino , Prevalencia , Factores de Riesgo , Zoonosis/epidemiología , Zoonosis/parasitología
15.
Mycopathologia ; 182(9-10): 947-952, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28523421

RESUMEN

Paracoccidioidomycosis is a systemic mycosis prevalent in Latin American countries, caused by the dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. The habitat of these fungi in nature remains undefined, although it is believed that infection occurs by inhalation of infective propagules present in soil. Sentinel animals, such as dogs, can be valuable epidemiological markers of paracoccidioidomycosis. Taking into account that paracoccidioidomycosis and visceral leishmaniasis may occur in the same area, the objective of this study was to evaluate the occurrence of P. brasiliensis infection in dogs positive for Leishmania sp. Serum samples of dogs positive (n = 199) and negative (n = 101) for Leishmania sp. were analyzed by the immunodiffusion test using P. brasiliensis exoantigen, and 22 samples (7.3%) were positive. The serum samples positive in the immunodiffusion test were also analyzed by Western blotting using the P. brasiliensis gp43 recombinant protein, and 86% of the samples were positive. A high positive correlation (r = 0.96) between positivity for Leishmania sp. and P. brasiliensis was observed. These data suggest an association between leishmaniasis and paracoccidioidomycosis in dogs.


Asunto(s)
Anticuerpos Antifúngicos/sangre , Coinfección/veterinaria , Enfermedades de los Perros/diagnóstico , Leishmaniasis/veterinaria , Paracoccidioides/inmunología , Paracoccidioidomicosis/veterinaria , Pruebas Serológicas , Animales , Western Blotting , Brasil , Coinfección/diagnóstico , Coinfección/microbiología , Enfermedades de los Perros/microbiología , Perros , Inmunodifusión , Leishmaniasis/complicaciones , Paracoccidioidomicosis/diagnóstico
16.
PLoS Negl Trop Dis ; 10(8): e0004885, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27529479

RESUMEN

Cryptococcus neoformans and Cryptococcus gattii are responsible globally for almost one million cryptococcosis cases yearly, mostly in immunocompromised patients, such as those living with HIV. Infections due to C. gattii have mainly been described in tropical and subtropical regions, but its adaptation to temperate regions was crucial in the species evolution and highlighted the importance of this pathogenic yeast in the context of disease. Cryptococcus gattii molecular type VGII has come to the forefront in connection with an on-going emergence in the Pacific North West of North America. Taking into account that previous work pointed towards South America as an origin of this species, the present work aimed to assess the genetic diversity within the Brazilian C. gattii VGII population in order to gain new insights into its origin and global dispersal from the South American continent using the ISHAM consensus MLST typing scheme. Our results corroborate the finding that the Brazilian C. gattii VGII population is highly diverse. The diversity is likely due to recombination generated from sexual reproduction, as evidenced by the presence of both mating types in clinical and environmental samples. The data presented herein strongly supports the emergence of highly virulent strains from ancestors in the Northern regions of Brazil, Amazonia and the Northeast. Numerous genotypes represent a link between Brazil and other parts of the world reinforcing South America as the most likely origin of the C. gattii VGII subtypes and their subsequent global spread, including their dispersal into North America, where they caused a major emergence.


Asunto(s)
Cryptococcus gattii/genética , Variación Genética , Evolución Biológica , Brasil/epidemiología , Criptococosis/epidemiología , Criptococosis/microbiología , Cryptococcus gattii/clasificación , Cryptococcus gattii/aislamiento & purificación , Cryptococcus neoformans/clasificación , Cryptococcus neoformans/genética , Genotipo , Humanos , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , América del Norte/epidemiología , Filogeografía , Bosque Lluvioso , Recombinación Genética , América del Sur/epidemiología
17.
Rev Inst Med Trop Sao Paulo ; 57 Suppl 19: 57-64, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26465371

RESUMEN

During recent decades, antifungal susceptibility testing has become standardized and nowadays has the same role of the antibacterial susceptibility testing in microbiology laboratories. American and European standards have been developed, as well as equivalent commercial systems which are more appropriate for clinical laboratories. The detection of resistant strains by means of these systems has allowed the study and understanding of the molecular basis and the mechanisms of resistance of fungal species to antifungal agents. In addition, many studies on the correlation of in vitro results with the outcome of patients have been performed, reaching the conclusion that infections caused by resistant strains have worse outcome than those caused by susceptible fungal isolates. These studies have allowed the development of interpretative breakpoints for Candida spp. and Aspergillus spp., the most frequent agents of fungal infections in the world. In summary, antifungal susceptibility tests have become essential tools to guide the treatment of fungal diseases, to know the local and global disease epidemiology, and to identify resistance to antifungals.


Asunto(s)
Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Candida/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/métodos , Aspergillus/clasificación , Candida/clasificación , Farmacorresistencia Fúngica , Humanos
18.
Rev. Inst. Med. Trop. Säo Paulo ; 57(supl.19): 57-64, Sept. 2015. tab
Artículo en Inglés | LILACS | ID: lil-762051

RESUMEN

SUMMARYDuring recent decades, antifungal susceptibility testing has become standardized and nowadays has the same role of the antibacterial susceptibility testing in microbiology laboratories. American and European standards have been developed, as well as equivalent commercial systems which are more appropriate for clinical laboratories. The detection of resistant strains by means of these systems has allowed the study and understanding of the molecular basis and the mechanisms of resistance of fungal species to antifungal agents. In addition, many studies on the correlation of in vitro results with the outcome of patients have been performed, reaching the conclusion that infections caused by resistant strains have worse outcome than those caused by susceptible fungal isolates. These studies have allowed the development of interpretative breakpoints for Candida spp. and Aspergillus spp., the most frequent agents of fungal infections in the world. In summary, antifungal susceptibility tests have become essential tools to guide the treatment of fungal diseases, to know the local and global disease epidemiology, and to identify resistance to antifungals.


RESUMONas últimas décadas, os testes de suscetibilidade a antifúngicos foram padronizados e, atualmente, servem tal como os testes de suscetibilidade a antibacterianos em laboratórios de microbiologia. Métodos de referência norte americanos e europeus foram desenvolvidos, assim como os equivalentes sistemas comerciais, estes últimos mais apropriados a laboratórios clínicos. A detecção de cepas resistentes por meio de tais sistemas permitiu o estudo e a compreensão das bases moleculares dos mecanismos de resistência de espécies fúngicas a fármacos antifúngicos. Além disso, foram realizados muitos estudos sobre a correlação de resultados obtidos in vitro com o desfecho clínico de pacientes permitindo a conclusão de que infecções por cepas resistentes têm pior evolução em relação às causadas por cepas sensíveis. Os estudos permitiram o estabelecimento de pontos de corte interpretativos (interpretative breakpoints development) para Candida spp. e Aspergillus spp., os agentes etiológicos mais frequentes de infecções fúngicas em todo o mundo. Em resumo, os testes de suscetibilidade representam uma ferramenta essencial para a orientação do tratamento de doenças fúngicas, para o conhecimento da epidemiologia local e global, bem como para a identificação de resistência a antifúngicos.


Asunto(s)
Humanos , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Candida/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/métodos , Aspergillus/clasificación , Candida/clasificación , Farmacorresistencia Fúngica
19.
FEMS Yeast Res ; 12(8): 890-6, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22883021

RESUMEN

We aim in this study to provide levels of susceptibility of 162 bloodstream isolates of non-Candida albicans and non-C. tropicalis species from a sentinel program conducted in 11 hospitals in Brazil. Additionally, we compared the broth microdilution (BMD) method of the European Committee of Susceptibility Testing (EUCAST) with Clinical Laboratory Standards Institute (CLSI) BMD method for fluconazole, itraconazole, voriconazole, and amphotericin B. The study included 103 C. parapsilosis, 38 C. glabrata, 8 C. orthopsilosis, and 7 C. krusei isolates, and single isolates of Pichia anomala, C. famata, C. lusitaniae, C. kefyr, C. guilliermondii, and C. metapsilosis. Of note, we observed cross-resistance between fluconazole and voriconazole for two isolates being one C. parapsilosis and one C. glabrata. Good essential agreement (EA) was observed between the EUCAST and the CLSI results for C. parapsilosis and for fluconazole, itraconazole, voriconazole, and amphotericin B, respectively: 98%, 99%, 98%, and 97%. Otherwise, for C. glabrata, the EA for fluconazole was 84.2% and for voriconazole 89.4%. Because data from Brazil are scarce, our results contribute to the consolidation of the database of candidemia agents and monitoring of trends in the profile of drug resistance.


Asunto(s)
Candida/efectos de los fármacos , Candida/aislamiento & purificación , Farmacorresistencia Fúngica/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/métodos , Anfotericina B/farmacología , Antifúngicos/farmacología , Sangre/microbiología , Brasil , Candida/clasificación , Candidemia/tratamiento farmacológico , Candidemia/microbiología , ADN de Hongos/genética , Fluconazol/farmacología , Humanos , Itraconazol/farmacología , Pichia/clasificación , Pichia/efectos de los fármacos , Pichia/aislamiento & purificación , Pirimidinas/farmacología , Centros de Atención Terciaria , Triazoles/farmacología , Voriconazol
20.
J Med Microbiol ; 61(Pt 7): 1003-1008, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22493277

RESUMEN

The Candida parapsilosis group encompasses three species: C. parapsilosis, Candida orthopsilosis and Candida metapsilosis. These species are phenotypically indistinguishable, and molecular methods are needed for their detection. We analysed 152 unique blood culture isolates of the C. parapsilosis group obtained during 1997-2011. The isolates were screened by PCR amplification of the gene encoding secondary alcohol dehydrogenase, followed by digestion with the restriction enzyme BanI. Isolates with RFLP patterns distinct from those of the C. parapsilosis group were characterized as C. parapsilosis sensu stricto (90.8 %), C. orthopsilosis (8.6 %) and C. metapsilosis (0.6 %). Antifungal susceptibility tests indicated that all isolates were susceptible to itraconazole, amphotericin B and caspofungin. Although C. orthopsilosis and C. metapsilosis isolates were susceptible to fluconazole, higher MICs (≥2 mg l(-1)) were observed for C. orthopsilosis. Three isolates (2.0 %) of C. parapsilosis sensu stricto were resistant to voriconazole. Five C. parapsilosis isolates (3.3 %) were intermediate, and a single isolate (0.7 %) was resistant (MIC 16 mg l(-1)) to fluconazole. These data were confirmed using reference strains. It was observed that C. parapsilosis isolates were less susceptible to all triazoles, and this finding deserves further attention to assess the appearance of cross-resistance phenomena. In conclusion, C. metapsilosis and C. orthopsilosis are involved in a small but significant number of invasive infections in Brazil.


Asunto(s)
Antifúngicos/farmacología , Candida/clasificación , Candida/efectos de los fármacos , Candidemia/epidemiología , Candidemia/microbiología , Brasil , Candida/genética , Candida/aislamiento & purificación , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación Molecular/métodos , Técnicas de Tipificación Micológica/métodos , Micología/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia
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