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1.
J Clin Microbiol ; 62(2): e0114023, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38265207

RESUMO

Candida glabrata is one of the most common causes of systemic candidiasis, often resistant to antifungal medications. To describe the genomic context of emerging resistance, we conducted a retrospective analysis of 82 serially collected isolates from 33 patients from population-based candidemia surveillance in the United States. We used whole-genome sequencing to determine the genetic relationships between isolates obtained from the same patient. Phylogenetic analysis demonstrated that isolates from 29 patients were clustered by patient. The median SNPs between isolates from the same patient was 30 (range: 7-96 SNPs), while unrelated strains infected four patients. Twenty-one isolates were resistant to echinocandins, and 24 were resistant to fluconazole. All echinocandin-resistant isolates carried a mutation either in the FKS1 or FKS2 HS1 region. Of the 24 fluconazole-resistant isolates, 17 (71%) had non-synonymous polymorphisms in the PDR1 gene, which were absent in susceptible isolates. In 11 patients, a genetically related resistant isolate was collected after recovering susceptible isolates, indicating in vivo acquisition of resistance. These findings allowed us to estimate the intra-host diversity of C. glabrata and propose an upper boundary of 96 SNPs for defining genetically related isolates, which can be used to assess donor-to-host transmission, nosocomial transmission, or acquired resistance. IMPORTANCE In our study, mutations associated to azole resistance and echinocandin resistance were detected in Candida glabrata isolates using a whole-genome sequence. C. glabrata is the second most common cause of candidemia in the United States, which rapidly acquires resistance to antifungals, in vitro and in vivo.


Assuntos
Candidemia , Equinocandinas , Humanos , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Candida glabrata , Candidemia/microbiologia , Estudos Retrospectivos , Filogenia , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Mutação , Genômica , Farmacorresistência Fúngica/genética
2.
Stud Mycol ; 100: 100133, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34909054

RESUMO

Candida glabrata is the second leading cause of candidemia in many countries and is one of the most concerning yeast species of nosocomial importance due to its increasing rate of antifungal drug resistance and emerging multidrug-resistant isolates. Application of multilocus sequence typing (MLST) to clinical C. glabrata isolates revealed an association of certain sequence types (STs) with drug resistance and mortality. The current C. glabrata MLST scheme is based on single nucleotide polymorphisms (SNPs) at six loci and is therefore relatively laborious and costly. Furthermore, only a few high-quality C. glabrata reference genomes are available, limiting rapid analysis of clinical isolates by whole genome sequencing. In this study we provide long-read based assemblies for seven additional clinical strains belonging to three different STs and use this information to simplify the C. glabrata MLST scheme. Specifically, a comparison of these genomes identified highly polymorphic loci (HPL) defined by frequent insertions and deletions (indels), two of which proved to be highly resolutive for ST. When challenged with 53 additional isolates, a combination of TRP1 (a component of the current MLST scheme) with either of the two HPL fully recapitulated ST identification. Therefore, our comparative genomic analysis identified a new typing approach combining SNPs and indels and based on only two loci, thus significantly simplifying ST identification in C. glabrata. Because typing tools are instrumental in addressing numerous clinical and biological questions, our new MLST scheme can be used for high throughput typing of C. glabrata in clinical and research settings.

4.
5.
Am J Transplant ; 17(1): 296-299, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28029734

RESUMO

November 11, 2016/65(44);1234-1237. What is already known about this topic? Candida auris is an emerging pathogenic fungus that has been reported from at least a dozen countries on four continents during 2009-2015. The organism is difficult to identify using traditional biochemical methods, some isolates have been found to be resistant to all three major classes of antifungal medications, and C. auris has caused health care-associated outbreaks. What is added by this report? This is the first description of C. auris cases in the United States. C. auris appears to have emerged in the United States only in the last few years, and U.S. isolates are related to isolates from South America and South Asia. Evidence from U.S. case investigations suggests likely transmission of the organism occurred in health care settings. What are the implications for public health practice? It is important that U.S. laboratories accurately identify C. auris and for health care facilities to implement recommended infection control practices to prevent the spread of C. auris. Local and state health departments and CDC should be notified of possible cases of C. auris and of isolates of C. haemulonii and Candida spp. that cannot be identified after routine testing.


Assuntos
Candida/isolamento & purificação , Candidíase/diagnóstico , Candidíase/microbiologia , Farmacorresistência Fúngica Múltipla , Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Doenças Transmissíveis Emergentes , Saúde Global , Humanos , Prognóstico , Fatores de Risco , Fatores de Tempo , Estados Unidos
6.
Antimicrob Agents Chemother ; 59(11): 6725-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282428

RESUMO

Neither breakpoints (BPs) nor epidemiological cutoff values (ECVs) have been established for Candida spp. with anidulafungin, caspofungin, and micafungin when using the Sensititre YeastOne (SYO) broth dilution colorimetric method. In addition, reference caspofungin MICs have so far proven to be unreliable. Candida species wild-type (WT) MIC distributions (for microorganisms in a species/drug combination with no detectable phenotypic resistance) were established for 6,007 Candida albicans, 186 C. dubliniensis, 3,188 C. glabrata complex, 119 C. guilliermondii, 493 C. krusei, 205 C. lusitaniae, 3,136 C. parapsilosis complex, and 1,016 C. tropicalis isolates. SYO MIC data gathered from 38 laboratories in Australia, Canada, Europe, Mexico, New Zealand, South Africa, and the United States were pooled to statistically define SYO ECVs. ECVs for anidulafungin, caspofungin, and micafungin encompassing ≥97.5% of the statistically modeled population were, respectively, 0.12, 0.25, and 0.06 µg/ml for C. albicans, 0.12, 0.25, and 0.03 µg/ml for C. glabrata complex, 4, 2, and 4 µg/ml for C. parapsilosis complex, 0.5, 0.25, and 0.06 µg/ml for C. tropicalis, 0.25, 1, and 0.25 µg/ml for C. krusei, 0.25, 1, and 0.12 µg/ml for C. lusitaniae, 4, 2, and 2 µg/ml for C. guilliermondii, and 0.25, 0.25, and 0.12 µg/ml for C. dubliniensis. Species-specific SYO ECVs for anidulafungin, caspofungin, and micafungin correctly classified 72 (88.9%), 74 (91.4%), 76 (93.8%), respectively, of 81 Candida isolates with identified fks mutations. SYO ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin, micafungin, and especially caspofungin, since testing the susceptibilities of Candida spp. to caspofungin by reference methodologies is not recommended.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Lipopeptídeos/farmacologia , Anidulafungina , Candida/genética , Caspofungina , Micafungina , Testes de Sensibilidade Microbiana , Mutação/genética
7.
Transpl Infect Dis ; 17(3): 467-76, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25677448

RESUMO

Cryptococcus gattii was recognized as an emerging infection in the Pacific Northwest in 2004. Out of 62 total infections in Oregon since the outbreak, 11 were in solid organ transplant (SOT) recipients. SOT recipients were more likely to have disseminated disease and higher mortality than normal hosts, who mostly had isolated mass lesions. The median time from transplantation to C. gattii diagnosis was 17.8 months. The primary sites of infection were lung (n = 4), central nervous system (n = 3), or both (n = 4). The Oregon-endemic strain, VGII (subtypes IIa and IIc) was present in 10 of 11 patients; the median fluconazole minimum inhibitory concentration (MIC) was 12 µg/mL (range 2-32 µg/mL) for this strain. We found C. gattii infection among organ transplant recipients was disseminated at diagnosis, had low cerebrospinal fluid cryptococcal antigen titers, and was associated with an elevated fluconazole MIC and high attributable mortality.


Assuntos
Antígenos de Fungos/líquido cefalorraquidiano , Criptococose/diagnóstico , Cryptococcus gattii/isolamento & purificação , Surtos de Doenças , Fluconazol/farmacologia , Transplante de Órgãos/efeitos adversos , Criptococose/microbiologia , Cryptococcus gattii/classificação , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/imunologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Oregon/epidemiologia , Estudos Retrospectivos , Transplantados
8.
Antimicrob Agents Chemother ; 58(2): 916-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24277027

RESUMO

Since epidemiological cutoff values (ECVs) using CLSI MICs from multiple laboratories are not available for Candida spp. and the echinocandins, we established ECVs for anidulafungin and micafungin on the basis of wild-type (WT) MIC distributions (for organisms in a species-drug combination with no detectable acquired resistance mechanisms) for 8,210 Candida albicans, 3,102 C. glabrata, 3,976 C. parapsilosis, 2,042 C. tropicalis, 617 C. krusei, 258 C. lusitaniae, 234 C. guilliermondii, and 131 C. dubliniensis isolates. CLSI broth microdilution MIC data gathered from 15 different laboratories in Canada, Europe, Mexico, Peru, and the United States were aggregated to statistically define ECVs. ECVs encompassing 97.5% of the statistically modeled population for anidulafungin and micafungin were, respectively, 0.12 and 0.03 µg/ml for C. albicans, 0.12 and 0.03 µg/ml for C. glabrata, 8 and 4 µg/ml for C. parapsilosis, 0.12 and 0.06 µg/ml for C. tropicalis, 0.25 and 0.25 µg/ml for C. krusei, 1 and 0.5 µg/ml for C. lusitaniae, 8 and 2 µg/ml for C. guilliermondii, and 0.12 and 0.12 µg/ml for C. dubliniensis. Previously reported single and multicenter ECVs defined in the present study were quite similar or within 1 2-fold dilution of each other. For a collection of 230 WT isolates (no fks mutations) and 51 isolates with fks mutations, the species-specific ECVs for anidulafungin and micafungin correctly classified 47 (92.2%) and 51 (100%) of the fks mutants, respectively, as non-WT strains. These ECVs may aid in detecting non-WT isolates with reduced susceptibility to anidulafungin and micafungin due to fks mutations.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Proteínas Fúngicas/genética , Lipopeptídeos/farmacologia , Anidulafungina , Candida/classificação , Candida/genética , Candida/isolamento & purificação , Candidíase/epidemiologia , Candidíase/microbiologia , Europa (Continente)/epidemiologia , Expressão Gênica , Humanos , Micafungina , Testes de Sensibilidade Microbiana , Mutação , América do Norte/epidemiologia , América do Sul/epidemiologia
9.
Antimicrob Agents Chemother ; 58(4): 2006-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24419346

RESUMO

Although epidemiological cutoff values (ECVs) have been established for Candida spp. and the triazoles, they are based on MIC data from a single laboratory. We have established ECVs for eight Candida species and fluconazole, posaconazole, and voriconazole based on wild-type (WT) MIC distributions for isolates of C. albicans (n=11,241 isolates), C. glabrata (7,538), C. parapsilosis (6,023), C. tropicalis (3,748), C. krusei (1,073), C. lusitaniae (574), C. guilliermondii (373), and C. dubliniensis (162). The 24-h CLSI broth microdilution MICs were collated from multiple laboratories (in Canada, Brazil, Europe, Mexico, Peru, and the United States). The ECVs for distributions originating from ≥6 laboratories, which included ≥95% of the modeled WT population, for fluconazole, posaconazole, and voriconazole were, respectively, 0.5, 0.06 and 0.03 µg/ml for C. albicans, 0.5, 0.25, and 0.03 µg/ml for C. dubliniensis, 8, 1, and 0.25 µg/ml for C. glabrata, 8, 0.5, and 0.12 µg/ml for C. guilliermondii, 32, 0.5, and 0.25 µg/ml for C. krusei, 1, 0.06, and 0.06 µg/ml for C. lusitaniae, 1, 0.25, and 0.03 µg/ml for C. parapsilosis, and 1, 0.12, and 0.06 µg/ml for C. tropicalis. The low number of MICs (<100) for other less prevalent species (C. famata, C. kefyr, C. orthopsilosis, C. rugosa) precluded ECV definition, but their MIC distributions are documented. Evaluation of our ECVs for some species/agent combinations using published individual MICs for 136 isolates (harboring mutations in or upregulation of ERG11, MDR1, CDR1, or CDR2) and 64 WT isolates indicated that our ECVs may be useful in distinguishing WT from non-WT isolates.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Fluconazol/farmacologia , Pirimidinas/farmacologia , Triazóis/farmacologia , Testes de Sensibilidade Microbiana , Voriconazol
10.
Antimicrob Agents Chemother ; 57(12): 5836-42, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24018263

RESUMO

Although Clinical and Laboratory Standards Institute (CLSI) clinical breakpoints (CBPs) are available for interpreting echinocandin MICs for Candida spp., epidemiologic cutoff values (ECVs) based on collective MIC data from multiple laboratories have not been defined. While collating CLSI caspofungin MICs for 145 to 11,550 Candida isolates from 17 laboratories (Brazil, Canada, Europe, Mexico, Peru, and the United States), we observed an extraordinary amount of modal variability (wide ranges) among laboratories as well as truncated and bimodal MIC distributions. The species-specific modes across different laboratories ranged from 0.016 to 0.5 µg/ml for C. albicans and C. tropicalis, 0.031 to 0.5 µg/ml for C. glabrata, and 0.063 to 1 µg/ml for C. krusei. Variability was also similar among MIC distributions for C. dubliniensis and C. lusitaniae. The exceptions were C. parapsilosis and C. guilliermondii MIC distributions, where most modes were within one 2-fold dilution of each other. These findings were consistent with available data from the European Committee on Antimicrobial Susceptibility Testing (EUCAST) (403 to 2,556 MICs) for C. albicans, C. glabrata, C. krusei, and C. tropicalis. Although many factors (caspofungin powder source, stock solution solvent, powder storage time length and temperature, and MIC determination testing parameters) were examined as a potential cause of such unprecedented variability, a single specific cause was not identified. Therefore, it seems highly likely that the use of the CLSI species-specific caspofungin CBPs could lead to reporting an excessive number of wild-type (WT) isolates (e.g., C. glabrata and C. krusei) as either non-WT or resistant isolates. Until this problem is resolved, routine testing or reporting of CLSI caspofungin MICs for Candida is not recommended; micafungin or anidulafungin data could be used instead.


Assuntos
Antifúngicos/uso terapêutico , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Equinocandinas/uso terapêutico , Anidulafungina , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candidíase/microbiologia , Caspofungina , Farmacorresistência Fúngica , Europa (Continente) , Humanos , Lipopeptídeos/uso terapêutico , Micafungina , Testes de Sensibilidade Microbiana/normas , Testes de Sensibilidade Microbiana/estatística & dados numéricos , América do Norte , Variações Dependentes do Observador , América do Sul , Especificidade da Espécie
11.
Transpl Infect Dis ; 15(2): E64-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23387927

RESUMO

Initial presentation of invasive fungal infections such as histoplasmosis can include non-specific clinical manifestations, especially in immunocompromised patients. A high index of suspicion is required to identify atypical manifestations of these diseases, which carry a high risk of mortality, if the diagnosis is delayed or missed. We describe a case of a kidney transplant recipient with cutaneous lesions as initial manifestation of progressive disseminated histoplasmosis where a skin biopsy was crucial to an early diagnosis.


Assuntos
Dermatomicoses/diagnóstico , Histoplasmose/diagnóstico , Transplante de Rim , Adulto , Antifúngicos/uso terapêutico , Dermatomicoses/tratamento farmacológico , Feminino , Histoplasmose/tratamento farmacológico , Humanos , Hospedeiro Imunocomprometido , Itraconazol/uso terapêutico , Ohio , Complicações Pós-Operatórias , Fatores de Tempo , Resultado do Tratamento , População Branca
12.
Antimicrob Agents Chemother ; 56(6): 3107-13, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22391546

RESUMO

Clinical breakpoints (CBPs) are not available for the Cryptococcus neoformans-Cryptococcus gattii species complex. MIC distributions were constructed for the wild type (WT) to establish epidemiologic cutoff values (ECVs) for C. neoformans and C. gattii versus amphotericin B and flucytosine. A total of 3,590 amphotericin B and 3,045 flucytosine CLSI MICs for C. neoformans (including 1,002 VNI isolates and 8 to 39 VNII, VNIII, and VNIV isolates) and 985 and 853 MICs for C. gattii, respectively (including 42 to 259 VGI, VGII, VGIII, and VGIV isolates), were gathered in 9 to 16 (amphotericin B) and 8 to 13 (flucytosine) laboratories (Europe, United States, Australia, Brazil, Canada, India, and South Africa) and aggregated for the analyses. Additionally, 442 amphotericin B and 313 flucytosine MICs measured by using CLSI-YNB medium instead of CLSI-RPMI medium and 237 Etest amphotericin B MICs for C. neoformans were evaluated. CLSI-RPMI ECVs for distributions originating in ≥3 laboratories (with the percentages of isolates for which MICs were less than or equal to ECVs given in parentheses) were as follows: for amphotericin B, 0.5 µg/ml for C. neoformans VNI (97.2%) and C. gattii VGI and VGIIa (99.2 and 97.5%, respectively) and 1 µg/ml for C. neoformans (98.5%) and C. gattii nontyped (100%) and VGII (99.2%) isolates; for flucytosine, 4 µg/ml for C. gattii nontyped (96.4%) and VGI (95.7%) isolates, 8 µg/ml for VNI (96.6%) isolates, and 16 µg/ml for C. neoformans nontyped (98.6%) and C. gattii VGII (97.1%) isolates. Other molecular types had apparent variations in MIC distributions, but the number of laboratories contributing data was too low to allow us to ascertain that the differences were due to factors other than assay variation. ECVs may aid in the detection of isolates with acquired resistance mechanisms.


Assuntos
Anfotericina B/farmacologia , Antibacterianos/farmacologia , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Flucitosina/farmacologia , Testes de Sensibilidade Microbiana
13.
Antimicrob Agents Chemother ; 56(11): 5898-906, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22948877

RESUMO

Epidemiological cutoff values (ECVs) for the Cryptococcus neoformans-Cryptococcus gattii species complex versus fluconazole, itraconazole, posaconazole, and voriconazole are not available. We established ECVs for these species and agents based on wild-type (WT) MIC distributions. A total of 2,985 to 5,733 CLSI MICs for C. neoformans (including isolates of molecular type VNI [MICs for 759 to 1,137 isolates] and VNII, VNIII, and VNIV [MICs for 24 to 57 isolates]) and 705 to 975 MICs for C. gattii (including 42 to 260 for VGI, VGII, VGIII, and VGIV isolates) were gathered in 15 to 24 laboratories (Europe, United States, Argentina, Australia, Brazil, Canada, Cuba, India, Mexico, and South Africa) and were aggregated for analysis. Additionally, 220 to 359 MICs measured using CLSI yeast nitrogen base (YNB) medium instead of CLSI RPMI medium for C. neoformans were evaluated. CLSI RPMI medium ECVs for distributions originating from at least three laboratories, which included ≥95% of the modeled WT population, were as follows: fluconazole, 8 µg/ml (VNI, C. gattii nontyped, VGI, VGIIa, and VGIII), 16 µg/ml (C. neoformans nontyped, VNIII, and VGIV), and 32 µg/ml (VGII); itraconazole, 0.25 µg/ml (VNI), 0.5 µg/ml (C. neoformans and C. gattii nontyped and VGI to VGIII), and 1 µg/ml (VGIV); posaconazole, 0.25 µg/ml (C. neoformans nontyped and VNI) and 0.5 µg/ml (C. gattii nontyped and VGI); and voriconazole, 0.12 µg/ml (VNIV), 0.25 µg/ml (C. neoformans and C. gattii nontyped, VNI, VNIII, VGII, and VGIIa,), and 0.5 µg/ml (VGI). The number of laboratories contributing data for other molecular types was too low to ascertain that the differences were due to factors other than assay variation. In the absence of clinical breakpoints, our ECVs may aid in the detection of isolates with acquired resistance mechanisms and should be listed in the revised CLSI M27-A3 and CLSI M27-S3 documents.


Assuntos
Antifúngicos/uso terapêutico , Criptococose/tratamento farmacológico , Criptococose/epidemiologia , Cryptococcus gattii/efeitos dos fármacos , Fluconazol/uso terapêutico , Itraconazol/uso terapêutico , Pirimidinas/uso terapêutico , Triazóis/uso terapêutico , Antifúngicos/farmacologia , Austrália/epidemiologia , Criptococose/microbiologia , Cryptococcus gattii/crescimento & desenvolvimento , Cryptococcus gattii/isolamento & purificação , Farmacorresistência Fúngica/efeitos dos fármacos , Europa (Continente)/epidemiologia , Fluconazol/farmacologia , Humanos , Índia/epidemiologia , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana , América do Norte/epidemiologia , Pirimidinas/farmacologia , África do Sul/epidemiologia , América do Sul/epidemiologia , Triazóis/farmacologia , Voriconazol
14.
J Clin Microbiol ; 50(4): 1199-203, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22278842

RESUMO

The echinocandin class of antifungal agents is considered to be the first-line treatment of bloodstream infections (BSI) due to Candida glabrata. Recent reports of BSI due to strains of C. glabrata resistant to both fluconazole and the echinocandins are of concern and prompted us to review the experience of two large surveillance programs, the SENTRY Antimicrobial Surveillance Program for the years 2006 through 2010 and the Centers for Disease Control and Prevention population-based surveillance conducted in 2008 to 2010. The in vitro susceptibilities of 1,669 BSI isolates of C. glabrata to fluconazole, voriconazole, anidulafungin, caspofungin, and micafungin were determined by CLSI broth microdilution methods. Fluconazole MICs of ≥64 µg/ml were considered resistant. Strains for which anidulafungin and caspofungin MICs were ≥0.5 µg/ml and for which micafungin MICs were ≥0.25 µg/ml were considered resistant. A total of 162 isolates (9.7%) were resistant to fluconazole, of which 98.8% were nonsusceptible to voriconazole (MIC > 0.5 µg/ml) and 9.3%, 9.3%, and 8.0% were resistant to anidulafungin, caspofungin, and micafungin, respectively. There were 18 fluconazole-resistant isolates that were resistant to one or more of the echinocandins (11.1% of all fluconazole-resistant isolates), all of which contained an acquired mutation in fks1 or fks2. By comparison, there were no echinocandin-resistant strains detected among 110 fluconazole-resistant isolates of C. glabrata tested in 2001 to 2004. These data document the broad emergence of coresistance over time to both azoles and echinocandins in clinical isolates of C. glabrata.


Assuntos
Antifúngicos/farmacologia , Candida glabrata/efeitos dos fármacos , Candidemia/microbiologia , Farmacorresistência Fúngica Múltipla/genética , Equinocandinas/farmacologia , Fluconazol/farmacologia , Adulto , Idoso , Candida glabrata/genética , Candida glabrata/isolamento & purificação , Feminino , Proteínas Fúngicas/genética , Glucosiltransferases/genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Vigilância de Evento Sentinela , Adulto Jovem
15.
J Clin Microbiol ; 50(6): 2040-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22461672

RESUMO

Clinical breakpoints (CBPs) and epidemiological cutoff values (ECVs) have been established for several Candida spp. and the newer triazoles and echinocandins but are not yet available for older antifungal agents, such as amphotericin B, flucytosine, or itraconazole. We determined species-specific ECVs for amphotericin B (AMB), flucytosine (FC) and itraconazole (ITR) for eight Candida spp. (30,221 strains) using isolates from 16 different laboratories in Brazil, Canada, Europe, and the United States, all tested by the CLSI reference microdilution method. The calculated 24- and 48-h ECVs expressed in µg/ml (and the percentages of isolates that had MICs less than or equal to the ECV) for AMB, FC, and ITR, respectively, were 2 (99.8)/2 (99.2), 0.5 (94.2)/1 (91.4), and 0.12 (95.0)/0.12 (92.9) for C. albicans; 2 (99.6)/2 (98.7), 0.5 (98.0)/0.5 (97.5), and 2 (95.2)/4 (93.5) for C. glabrata; 2 (99.7)/2 (97.3), 0.5 (98.7)/0.5 (97.8), and 05. (99.7)/0.5 (98.5) for C. parapsilosis; 2 (99.8)/2 (99.2), 0.5 (93.0)/1 (90.5), and 0.5 (97.8)/0.5 (93.9) for C. tropicalis; 2 (99.3)/4 (100.0), 32 (99.4)/32 (99.3), and 1 (99.0)/2 (100.0) for C. krusei; 2 (100.0)/4 (100.0), 0.5 (95.3)/1 (92.9), and 0.5 (95.8)/0.5 (98.1) for C. lusitaniae; -/2 (100.0), 0.5 (98.8)/0.5 (97.7), and 0.25 (97.6)/0.25 (96.9) for C. dubliniensis; and 2 (100.0)/2 (100.0), 1 (92.7)/-, and 1 (100.0)/2 (100.0) for C. guilliermondii. In the absence of species-specific CBP values, these wild-type (WT) MIC distributions and ECVs will be useful for monitoring the emergence of reduced susceptibility to these well-established antifungal agents.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candidíase/microbiologia , Flucitosina/farmacologia , Itraconazol/farmacologia , Brasil , Canadá , Candida/isolamento & purificação , Europa (Continente) , Humanos , Testes de Sensibilidade Microbiana/normas , Estados Unidos
16.
Drug Resist Updat ; 14(3): 164-76, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21353623

RESUMO

The CLSI established clinical breakpoints (CBPs) for caspofungin (CSF), micafungin (MCF) and anidulafungin (ANF) versus Candida. The same CBP (susceptible (S): MIC ≤ 2 mcg/ml; non-S: MIC > 2 mcg/ml) was applied to all echinocandins and species. More data now allow reassessment of these CBPs. We examined cases of echinocandin failure where both MICs and fks mutations were assessed; wild type (WT) MICs and epidemiological cutoff values (ECVs) for a large Candida collection; molecular analysis of fks hotspots for Candida with known MICs; and pharmacokinetic and pharmacodynamic (PK/PD) data. We applied these findings to propose new species-specific CBPs for echinocandins and Candida. Of 18 candidiasis cases refractory to echinocandins and with fks mutations, 28% (CSF), 58% (ANF) and 66% (MCF) had MICs in the S category using CBP of ≤ 2 mcg/ml, while 0-8% would be S using CBP of ≤ 0.25 mcg/ml. WT MIC distributions revealed ECV ranges of 0.03-0.25 mcg/ml for all major species except C. parapsilosis (1-4 mcg/ml) and C. guilliermondii (4-16 mcg/ml). Among Candida tested for fks mutations, only 15.7-45.1% of 51 mutants were detected using the CBP for NS of >2 mcg/ml. In contrast, a cutoff of >0.25 mcg/ml for C. albicans, C. tropicalis, C. krusei, and C. dubliniensis detected 85.6% (MCF) to 95.2% (CSF) of 21 mutant strains. Likewise, a cutoff of >0.12 mcg/ml for ANF and CSF and of >0.06 mcg/ml for MCF detected 93% (ANF) to 97% (CSF, MCF) of 30 mutant strains of C. glabrata. These data, combined with PK/PD considerations, support CBPs of ≤ 0.25 mcg/ml (S), 0.5 mcg/ml (I), ≥ 1 (R) for CSF/MCF/ANF and C. albicans, C. tropicalis and C. krusei and ≤ 2 mcg/ml (S), 4 mcg/ml (I), and ≥ 8 mcg/ml (R) for these agents and C. parapsilosis. The CBPs for ANF and CSF and C. glabrata are ≤ 0.12 mcg/ml (S), 0.25 mcg/ml (I), and ≥ 0.5 mcg/ml (R), whereas those for MCF are ≤ 0.06 mcg/ml (S), 0.12 mcg/ml (I), and ≥ 0.25 mcg/ml (R). New, species-specific CBPs for Candida and the echinocandins are more sensitive to detect emerging resistance associated with fks mutations, and better able to predict risk for clinical failure.


Assuntos
Antifúngicos/administração & dosagem , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Farmacorresistência Fúngica/efeitos dos fármacos , Glucosiltransferases/antagonistas & inibidores , Anidulafungina , Antifúngicos/uso terapêutico , Candida/genética , Candidíase/metabolismo , Candidíase/microbiologia , Caspofungina , Farmacorresistência Fúngica/genética , Equinocandinas/administração & dosagem , Equinocandinas/uso terapêutico , Fluconazol/farmacologia , Glucosiltransferases/metabolismo , Humanos , Concentração Inibidora 50 , Lipopeptídeos/administração & dosagem , Lipopeptídeos/uso terapêutico , Micafungina , Testes de Sensibilidade Microbiana , Mutação , Proteoglicanas , Ensaios Clínicos Controlados Aleatórios como Assunto , Especificidade da Espécie , Resultado do Tratamento , beta-Glucanas/metabolismo
17.
Clin Infect Dis ; 53(12): 1188-95, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22016503

RESUMO

BACKGROUND: Cryptococcus gattii (Cg) has caused increasing infections in the US Pacific Northwest (PNW) since 2004. We describe this outbreak and compare clinical aspects of infection in the United States among patients infected with different Cg genotypes. METHODS: Beginning in 2005, PNW state health departments conducted retrospective and prospective passive surveillance for Cg infections, including patient interviews and chart reviews; clinical isolates were genotyped at the US Centers for Disease Control and Prevention (CDC). We examined symptom frequency and underlying conditions in US patients with Cg infection and modeled factors associated with death. RESULTS: From 1 December 2004 to July 2011, 96 Cg infections were reported to the CDC. Eighty-three were in patients in or travelers to the PNW, 78 of which were genotypes VGIIa, VGIIb, or VGIIc (outbreak strains). Eighteen patients in and outside the PNW had other molecular type Cg infections (nonoutbreak strains). Patients with outbreak strain infections were more likely than those with nonoutbreak-strain infections to have preexisting conditions (86% vs 31%, respectively; P < .0001) and respiratory symptoms (75% vs 36%, respectively; P = .03) and less likely to have central nervous system (CNS) symptoms (37% vs 90%, respectively; P = .008). Preexisting conditions were associated with increased pneumonia risk and decreased risk of meningitis and CNS symptoms. Nineteen (33%) of 57 patients died. Past-year oral steroid use increased odds of death in multivariate analysis (P = .05). CONCLUSIONS: Clinical differences may exist between outbreak-strain (VGIIa, VGIIb, and VGIIc) and nonoutbreak-strain Cg infections in the United States. Clinicians should have a low threshold for testing for Cg, particularly among patients with recent travel to the PNW.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/patologia , Criptococose/epidemiologia , Criptococose/patologia , Cryptococcus gattii/isolamento & purificação , Surtos de Doenças , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes/microbiologia , Criptococose/microbiologia , Cryptococcus gattii/classificação , Cryptococcus gattii/genética , Cryptococcus gattii/patogenicidade , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Técnicas de Tipagem Micológica , Noroeste dos Estados Unidos/epidemiologia , Fatores de Risco , Adulto Jovem
19.
Mol Cell Biol ; 14(6): 3623-33, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8196608

RESUMO

The binding of a U1 small nuclear ribonucleoprotein (snRNP) particle to the 5' splice site region of a pre-mRNA is a primary step of intron recognition. In this report, we identify a novel 75-kDa polypeptide of Saccharomyces cerevisiae, Prp39p, necessary for the stable interaction of mRNA precursors with the snRNP components of the pre-mRNA splicing machinery. In vivo, temperature inactivation or metabolic depletion of Prp39p blocks pre-mRNA splicing and causes growth arrest. Analyses of cell extracts reveal a specific and dramatic increase in the electrophoretic mobility of the U1 snRNP particle upon Prp39p depletion and demonstrate that extracts deficient in Prp39p activity are unable to form either the CC1 or CC2 commitment complex band characteristic of productive U1 snRNP/pre-mRNA association. Immunological studies establish that Prp39p is uniquely associated with the U1 snRNP and is recruited with the U1 snRNP into splicing complexes. On the basis of these and related observations, we propose that Prp39p functions, at least in part, prior to stable branch point recognition by the U1 snRNP particle to facilitate or stabilize the U1 snRNP/5' splice site interaction.


Assuntos
Precursores de RNA/metabolismo , Splicing de RNA , RNA Fúngico/metabolismo , Ribonucleoproteína Nuclear Pequena U1/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Genes Fúngicos , Dados de Sequência Molecular , Mutagênese Insercional , Reação em Cadeia da Polimerase , RNA Fúngico/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/metabolismo , Sequências Reguladoras de Ácido Nucleico , Saccharomyces cerevisiae/genética
20.
J Dent Res ; 78(4): 857-68, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10326730

RESUMO

Candida colonization of the oral cavity increases in the elderly. A major predisposing condition is denture use, which also increases in the elderly. To test whether the increase in colonization is age-related in a fashion independent of denture use, we analyzed the frequency (incidence) of carriage, the intensity of carriage, the multiplicity of species, and the genetic relatedness of strains in the oral cavities of 93 test subjects separated into the three age groups: 60 to 69 yr, 70 to 79 yr, and > or = 80 yr. Each age group was further subdivided into subjects with and without dentures, and into males and females. The results demonstrate that the frequency of carriage, the intensity of carriage, and multispecies carriage all increase as a function of age and differ according to gender, in both cases independent of denture use, suggesting that the natural suppression of yeast carriage in the oral cavity breaks down in the elderly. In addition, it is demonstrated that Candida glabrata colonizes the oral cavities of elderly individuals without dentures only after 80 yr of age, suggesting that there are age-related compromising conditions other than denture use in this most elderly age group.


Assuntos
Candida/isolamento & purificação , Boca/microbiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Southern Blotting/métodos , Southern Blotting/estatística & dados numéricos , Candida/genética , Candidíase Bucal/epidemiologia , Candidíase Bucal/microbiologia , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Impressões Digitais de DNA/métodos , Impressões Digitais de DNA/estatística & dados numéricos , Dentaduras/estatística & dados numéricos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Especificidade da Espécie
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