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1.
bioRxiv ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38948750

RESUMO

The global epidemic of drug-resistant Candida auris continues unabated. We do not know what caused the unprecedented appearance of pan-drug resistant (PDR) Candida auris strains in a hospitalized patient in New York; the initial report highlighted both known and unique mutations in the prominent gene targets of azoles, amphotericin B, echinocandins, and flucytosine antifungal drugs. However, the factors that allow C. auris to acquire multi-drug resistance and pan-drug resistance are not known. Therefore, we conducted a comprehensive genomic, transcriptomic, and phenomic analysis to better understand PDR C. auris . Among 1,570 genetic variants in drug-resistant C. auris , 299 were unique to PDR strains. The whole genome sequencing results suggested perturbations in genes associated with nucleotide biosynthesis, mRNA processing, and nuclear export of mRNA. Whole transcriptome sequencing of PDR C. auris revealed two genes to be significantly differentially expressed - a DNA repair protein and DNA replication-dependent chromatin assembly factor 1. Of 59 novel transcripts, 12 candidate transcripts had no known homology among expressed transcripts found in other organisms. We observed no fitness defects among multi-drug resistant (MDR) and PDR C. auris strains grown in nutrient-deficient or - enriched media at different temperatures. Phenotypic profiling revealed wider adaptability to nitrogenous nutrients with an uptick in the utilization of substrates critical in upper glycolysis and tricarboxylic acid cycle. Structural modelling of 33-amino acid deletion in the gene for uracil phosphoribosyl transferase suggested an alternate route in C. auris to generate uracil monophosphate that does not accommodate 5-fluorouracil as a substrate. Overall, we find evidence of metabolic adaptations in MDR and PDR C. auris in response to antifungal drug lethality without deleterious fitness costs.

2.
J Clin Microbiol ; 62(7): e0052524, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38888304

RESUMO

Candida auris is a multidrug-resistant fungal pathogen with a propensity to colonize humans and persist on environmental surfaces. C. auris invasive fungal disease is being increasingly identified in acute and long-term care settings. We have developed a prototype cartridge-based C. auris surveillance assay (CaurisSurV cartridge; "research use only") that includes integrated sample processing and nucleic acid amplification to detect C. auris from surveillance skin swabs in the GeneXpert instrument and is designed for point-of-care use. The assay limit of detection (LoD) in the skin swab matrix was 10.5 and 14.8 CFU/mL for non-aggregative (AR0388) and aggregative (AR0382) strains of C. auris, respectively. All five known clades of C. auris were detected at 2-3-5× (31.5-52.5 CFU/mL) the LoD. The assay was validated using a total of 85 clinical swab samples banked at two different institutions (University of California Los Angeles, CA and Wadsworth Center, NY). Compared to culture, sensitivity was 96.8% (30/31) and 100% (10/10) in the UCLA and Wadsworth cohorts, respectively, providing a combined sensitivity of 97.5% (40/41), and compared to PCR, the combined sensitivity was 92% (46/50). Specificity was 100% with both clinical (C. auris negative matrix, N = 31) and analytical (non-C. auris strains, N = 32) samples. An additional blinded study with N = 60 samples from Wadsworth Center, NY yielded 97% (29/30) sensitivity and 100% (28/28) specificity. We have developed a completely integrated, sensitive, specific, and 58-min prototype test, which can be used for routine surveillance of C. auris and might help prevent colonization and outbreaks in acute and chronic healthcare settings. IMPORTANCE: This study has the potential to offer a better solution to healthcare providers at hospitals and long-term care facilities in their ongoing efforts for effective and timely control of Candida auris infection and hence quicker response for any potential future outbreaks.


Assuntos
Candida auris , Candidíase , Sensibilidade e Especificidade , Humanos , Candidíase/diagnóstico , Candidíase/microbiologia , Candida auris/genética , Controle de Infecções/métodos , Monitoramento Epidemiológico , Pele/microbiologia , Limite de Detecção , Sistemas Automatizados de Assistência Junto ao Leito , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular/métodos , Candida/isolamento & purificação , Candida/genética , Candida/classificação
3.
JAMA Dermatol ; 160(7): 783-785, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38837127

RESUMO

This case report describes a patient with Trichophyton mentagrophytes internal transcribed spacer genotype VII resulting in tinea genitalis, glutealis, and corporis.


Assuntos
Tinha , Humanos , Tinha/transmissão , Tinha/diagnóstico , Tinha/microbiologia , Feminino , Masculino , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/transmissão , Infecções Sexualmente Transmissíveis/microbiologia , Adulto
4.
JAMA Dermatol ; 160(7): 701-709, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38748419

RESUMO

Importance: Trichophyton indotineae is an emerging dermatophyte causing outbreaks of extensive tinea infections often unresponsive to terbinafine. This species has been detected worldwide and in multiple US states, yet detailed US data on infections with T indotineae are sparse and could improve treatment practices and medical understanding of transmission. Objective: To correlate clinical features of T indotineae infections with in vitro antifungal susceptibility testing results, squalene epoxidase gene sequence variations, and isolate relatedness using whole-genome sequencing. Design, Setting, and Participants: This retrospective cohort study of patients with T indotineae infections in New York City spanned May 2022 to May 2023. Patients with confirmed T indotineae infections were recruited from 6 New York City medical centers. Main Outcome and Measure: Improvement or resolution at the last follow-up assessment. Results: Among 11 patients with T indotineae (6 male and 5 female patients; median [range] age, 39 [10-65] years), 2 were pregnant; 1 had lymphoma; and the remainder were immunocompetent. Nine patients reported previous travel to Bangladesh. All had widespread lesions with variable scale and inflammation, topical antifungal monotherapy failure, and diagnostic delays (range, 3-42 months). Terbinafine treatment failed in 7 patients at standard doses (250 mg daily) for prolonged duration; these patients also had isolates with amino acid substitutions at positions 393 (L393S) or 397 (F397L) in squalene epoxidase that correlated with elevated terbinafine minimum inhibitory concentrations of 0.5 µg/mL or higher. Patients who were treated with fluconazole and griseofulvin improved in 2 of 4 and 2 of 5 instances, respectively, without correlation between outcomes and antifungal minimum inhibitory concentrations. Furthermore, 5 of 7 patients treated with itraconazole cleared or had improvement at the last follow-up, and 2 of 7 were lost to follow-up or stopped treatment. Based on whole-genome sequencing analysis, US isolates formed a cluster distinct from Indian isolates. Conclusion and Relevance: The results of this case series suggest that disease severity, diagnostic delays, and lack of response to typically used doses and durations of antifungals for tinea were common in this primarily immunocompetent patient cohort with T indotineae, consistent with published data. Itraconazole was generally effective, and the acquisition of infection was likely in Bangladesh.


Assuntos
Antifúngicos , Testes de Sensibilidade Microbiana , Tinha , Trichophyton , Humanos , Masculino , Feminino , Antifúngicos/farmacologia , Antifúngicos/administração & dosagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Tinha/tratamento farmacológico , Tinha/microbiologia , Tinha/diagnóstico , Adulto , Idoso , Trichophyton/efeitos dos fármacos , Trichophyton/genética , Trichophyton/isolamento & purificação , Adolescente , Criança , Adulto Jovem , Sequenciamento Completo do Genoma , Esqualeno Mono-Oxigenase/genética , Cidade de Nova Iorque/epidemiologia , Terbinafina/farmacologia , Terbinafina/administração & dosagem , Farmacorresistência Fúngica , Estudos de Coortes
6.
J Clin Microbiol ; 61(4): e0176722, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36975998

RESUMO

Candida auris is a multidrug-resistant yeast pathogen causing outbreaks in health care facilities worldwide, and the emergence of echinocandin-resistant C. auris is a concern. Currently used Clinical and Laboratory Standards Institute (CLSI) and commercial antifungal susceptibility tests (AFST) are phenotype-based, slow, and not scalable, limiting their effectiveness in the surveillance of echinocandin-resistant C. auris. The urgent need for accurate and rapid methods of assessment of echinocandin resistance cannot be overstated, as this class of antifungal drugs is preferred for patient management. We report the development and validation of a TaqMan chemistry probe-based fluorescence melt curve analysis (FMCA) following asymmetric polymerase chain reaction (PCR) to assess mutations within the hot spot one (HS1) region of FKS1, the gene responsible for encoding 1,3-ß-d-glucan synthase that is a target for echinocandins. The assay correctly identified F635C, F635Y, F635del, F635S, S639F or S639Y, S639P, and D642H/R645T mutations. Of these mutations, F635S and D642H/R645T were not involved in echinocandin resistance, while the rest were, as confirmed by AFST. Of 31 clinical cases, the predominant mutation conferring echinocandin resistance was S639F/Y (20 cases) followed by S639P (4 cases), F635del (4 cases), F635Y (2 cases), and F635C (1 case). The FMCA assay was highly specific and did not cross-react with closely and distantly related Candida and other yeast and mold species. Structural modeling of the Fks1 protein, its mutants, and docked conformations of three echinocandin drugs suggest a plausible Fks1 binding orientation for echinocandins. These findings lay the groundwork for future evaluations of additional FKS1 mutations and their impact on the development of drug resistance. The TaqMan chemistry probe-based FMCA would allow rapid, high throughput, and accurate detection of FKS1 mutations conferring echinocandin resistance in C. auris.


Assuntos
Antifúngicos , Candida auris , Farmacorresistência Fúngica Múltipla , Equinocandinas , Proteínas Fúngicas , Glucosiltransferases , Reação em Cadeia da Polimerase em Tempo Real , Candida auris/efeitos dos fármacos , Candida auris/genética , Candida auris/isolamento & purificação , Equinocandinas/farmacologia , Antifúngicos/farmacologia , Sondas Moleculares/química , Farmacorresistência Fúngica Múltipla/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Desnaturação de Ácido Nucleico , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Glucosiltransferases/química , Glucosiltransferases/genética , Conformação Proteica em alfa-Hélice/genética , Mutação , Candidíase Invasiva/diagnóstico , Candidíase Invasiva/microbiologia , Fluorescência , Análise Mutacional de DNA/métodos
7.
Am J Infect Control ; 51(8): 866-870, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36736380

RESUMO

BACKGROUND: This pilot project implemented admission screening for Candida auris (C. auris) using real-time polymerase chain reaction (rt-PCR) in select high-risk units within health care facilities in New York City. METHODS: An admission screening encounter consisted of collecting 2 swabs, to be tested by rt-PCR, and a data collection form for individuals admitted to ventilator units at 2 nursing homes (NHA and NHB), and the ventilator/pulmonary unit, intensive care unit, and cardiac care unit at a hospital (Hospital C) located in New York City from November 2017 to November 2019. RESULTS: C. auris colonization was identified in 6.9% (n = 188/2,726) of admissions to participating units. Rates were higher among admissions to NHA and NHB (20.7% and 22.0%, respectively) than Hospital C (3.6%). Within Hospital C, the ventilator/pulmonary unit had a higher rate (5.7%) than the intensive care unit (3.8%) or cardiac care unit (2.5%). DISCUSSION: Consistent with prior research, we found that individuals admitted to ventilator units were at higher risk of C. auris colonization. CONCLUSIONS: This project demonstrates the utility of admission screening using rt-PCR testing to rapidly identify C. auris colonization among admissions to health care facilities so that appropriate transmission-based precautions and control measures can be implemented rapidly to help decrease transmission.


Assuntos
Candida , Candidíase , Humanos , Candida/genética , Candidíase/diagnóstico , Candida auris , Cidade de Nova Iorque/epidemiologia , Projetos Piloto , Casas de Saúde , Atenção à Saúde , Antifúngicos
8.
Mycopathologia ; 187(5-6): 527-534, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36355325

RESUMO

Candida auris is a nosocomial fungal pathogen of prime importance due to its global emergence and rapid spread in healthcare facilities worldwide. One important concern is that routine, conventional methods fail to identify C. auris. While molecular and protein-based assays accurately detect/identify C. auris, these methods are time-consuming, expensive, and require expertise. Therefore, the objective of the present study was to assess the potential use of a novel chromogenic medium, CHROMagar™ Candida Plus, as an economical alternative to expensive and laborious diagnostic tests. We compared CHROMagar™ Candida Plus with the standard enrichment (salt Sabouraud Dulcitol broth) medium to test the recovery efficiency of C. auris from surveillance samples. We also tested CHROMagar™ Candida Plus for its ability to distinguish C. auris from other yeast species. One hundred surveillance samples were cultured on CHROMagar™ Candida Plus and Dulcitol broth and incubated at 37 °C and 40 °C, respectively. Additionally, 32 Candida and yeast species were cultured on CHROMagar™ Candida Plus at 37 °C for three days to rule out any close resemblance to C. auris. Of 100 surveillance samples tested, 69 yielded presumptive positive C. auris exhibiting creamy pink colonies with a blue halo on CHROMagar™ Candida Plus within three days of incubation, and MALDI-TOF MS confirmed all by day 4. On the other hand, 69 of 100 surveillance samples yielded turbidity in Dulcitol broth by days 3-14 with final MALDI identification by days 5 to 17. Both media failed to identify one sample each, resulting in assay sensitivity and specificity of 99% and 97%, respectively. Of Candida and yeast species tested, 75-80% of C. metapsilosis and C. orthospilosis were misidentified as C. auris. However, previous studies indicated that these species are rarely detected in surveillance screening of C. auris. Naganishia diffluens also resembled C. auris, although it required different temperature growth (30 °C). In conclusion, CHROMagar™ Candida Plus provides rapid presumptive identification of C. auris. It would be another valuable tool in surveillance efforts to control the spread of C. auris in healthcare.


Assuntos
Candida auris , Candida , Candida parapsilosis , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Galactitol
9.
ACS Infect Dis ; 8(9): 1851-1868, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-35948057

RESUMO

Drug resistance is a significant concern in the treatment of diseases, including cryptococcosis caused by Cryptococcus neoformans (Cne) and Cryptococcus gattii (Cga). Alternative drug targets are necessary to overcome drug resistance before it attains a critical stage. Splicing of inteins from pro-protein precursors is crucial for activities of essential proteins hosting intein elements in many organisms, including human pathogens such as Cne and Cga. Through a high-throughput screening, we identified calcimycin (CMN) as a potent Prp8 intein splicing inhibitor with a minimum inhibitory concentration (MIC) of 1.5 µg/mL against the wild-type Cne-H99 (Cne-WT or Cne). In contrast, CMN inhibited the intein-less mutant strain (Cne-Mut) with a 16-fold higher MIC. Interestingly, Aspergillus fumigatus and a few Candida species were resistant to CMN. Further studies indicated that CMN reduced virulence factors such as urease activity, melanin production, and biofilm formation in Cne. CMN also inhibited Cne intracellular infection in macrophages. In a target-specific split nanoluciferase assay, the IC50 of CMN was 4.6 µg/mL. Binding of CMN to recombinant Prp8 intein was demonstrated by thermal shift assay and microscale thermophoresis. Treating Cne cells with CMN reduced intein splicing. CMN was fungistatic and showed a synergistic effect with the known antifungal drug amphotericin B. Finally, CMN treatment at 20 mg/kg body weight led to 60% reduction in lung fungal load in a cryptococcal pulmonary infection mouse model. Overall, CMN represents a potent antifungal with a novel mechanism of action to treat Cne and possibly Cga infections.


Assuntos
Criptococose , Cryptococcus neoformans , Animais , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Calcimicina/metabolismo , Calcimicina/farmacologia , Criptococose/tratamento farmacológico , Proteínas Fúngicas/química , Humanos , Inteínas , Camundongos , Alinhamento de Sequência
10.
Antimicrob Agents Chemother ; 66(7): e0005322, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35770999

RESUMO

Candida auris is an urgent antimicrobial resistance threat due to its global emergence, high mortality, and persistent transmissions. Nearly half of C. auris clinical and surveillance cases in the United States are from the New York and New Jersey Metropolitan area. We performed genome, and drug-resistance analysis of C. auris isolates from a patient who underwent multi-visceral transplantation. Whole-genome comparisons of 19 isolates, collected over 72 days, revealed closed similarity (Average Nucleotide Identity > 0.9996; Aligned Percentage > 0.9764) and a distinct subcluster of NY C. auris South Asia Clade I. All isolates had azole-linked resistance in ERG11(K143R) and CDR1(V704L). Echinocandin resistance first appeared with FKS1(S639Y) mutation and then a unique FKS1(F635C) mutation. Flucytosine-resistant isolates had mutations in FCY1, FUR1, and ADE17. Two pan-drug-resistant C. auris isolates had uracil phosphoribosyltransferase deletion (FUR1[1Δ33]) and the elimination of FUR1 expression, confirmed by a qPCR test developed in this study. Besides ERG11 mutations, four amphotericin B-resistant isolates showed no distinct nonsynonymous variants suggesting unknown genetic elements driving the resistance. Pan-drug-resistant C. auris isolates were not susceptible to two-drug antifungal combinations tested by checkerboard, Etest, and time-kill methods. The fungal population pattern, discerned from SNP phylogenetic analysis, was consistent with in-hospital or inpatient evolution of C. auris isolates circulating locally and not indicative of a recent introduction from elsewhere. The emergence of pan-drug-resistance to four major classes of antifungals in C. auris is alarming. Patients at high risk for drug-resistant C. auris might require novel therapeutic strategies and targeted pre-and/or posttransplant surveillance.


Assuntos
Antifúngicos , Farmacorresistência Fúngica , Antifúngicos/farmacologia , Candida auris , Farmacorresistência Fúngica/genética , Humanos , Testes de Sensibilidade Microbiana , Filogenia
11.
J Fungi (Basel) ; 8(2)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35205920

RESUMO

Candida blankii is a recently recognized human pathogen, with most cases of the infection being reported in the immunocompromised. We here describe the case of a critically ill elderly woman with COVID-19 who developed a C. blankii bloodstream infection from a femoral central venous catheter. Aspergillus niger was also isolated from her respiratory secretions. The patient was started on voriconazole for empiric coverage of both A. niger, and at that time, unidentified yeast was found in the blood. Fevers persisted, and the patient expired six days after the yeast was first isolated. Almost one month after her death, C. blankii was identified as the cause of fungemia by sequencing of the internal transcribed spacer (ITS) region of the ribosomal gene and BLAST searching against two databases (performed by a reference laboratory). The isolate demonstrated high minimum inhibitory concentrations (MICs) to azoles and low MICs to amphotericin B, similar to previously described isolates. Timely identification of C. blankii would have prompted different empiric antifungal choices and possibly changed the final outcome. Clinicians should be aware of the pathological potential of C. blankii, the challenges of correctly identifying the organism, and its susceptibility patterns to common antifungals. There is an urgent need to improve assays for C. blankii identification, which will aid in accurate and timely pathogen identification, and appropriate therapeutic management.

12.
Antimicrob Agents Chemother ; 66(3): e0224221, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35007140

RESUMO

About 55% of U.S. Candida auris clinical cases were reported from New York and New Jersey from 2016 through 2020. Nearly all New York-New Jersey clinical isolates (99.8%) were fluconazole resistant, and 50% were amphotericin B resistant. Echinocandin resistance increased from 0% to 4% and pan-resistance increased from 0 to <1% for New York C. auris clinical isolates but not for New Jersey, highlighting the regional differences.


Assuntos
Antifúngicos , Candida , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida auris , Testes de Sensibilidade Microbiana , New Jersey/epidemiologia , New York/epidemiologia
13.
J Clin Microbiol ; 60(2): e0077921, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-34878804

RESUMO

Ongoing health care-associated outbreaks of the multidrug-resistant yeast Candida auris have prompted the development of several rapid DNA-based molecular diagnostic tests. These tests do not distinguish between live and dead C. auris cells, limiting their use for environmental surveillance and containment efforts. We addressed this critical gap by developing a reverse transcription (RT)-quantitative real-time PCR (RT-qPCR) assay to rapidly detect live C. auris in health care environments. This assay targeted the internal transcribed spacer 2 (ITS2) ribosomal gene by obtaining pure RNA followed by reverse transcription (ITS2 cDNA) and qPCR. ITS2 cDNA was not detectable in bleach-killed cells but was detectable in heat- and ethanol-killed C. auris cells. The assay was highly sensitive, with a detection limit of 10 CFU per RT-qPCR. Validation studies yielded positive cycle threshold (CT) values from sponge matrix samples spiked with 102 to 105 CFU of live C. auris, while dead (bleach-killed) C. auris (105/mL) or other live Candida species (105/mL) had no CT values. Finally, 33 environmental samples positive for C. auris DNA but negative by culture were all negative by RT-qPCR assay, confirming the concordance between culture and the PCR assay. The RT-qPCR assay appears highly reproducible, robust, and specific for detecting live C. auris from environmental samples. The Candida auris RT-qPCR assay could be an invaluable tool in surveillance efforts to control the spread of live C. auris in health care environments.


Assuntos
Candida auris , Candidíase , Candidíase/diagnóstico , Candidíase/epidemiologia , Atenção à Saúde , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Transcrição Reversa , Sensibilidade e Especificidade
14.
Am J Infect Control ; 50(3): 358-360, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34793894

RESUMO

Candida auris (C. auris) is a globally emerging multidrug-resistant yeast. New York State (NYS) first detected C. auris in July 2016 and is the state most affected. This brief report describes characteristics of the first 114 individuals colonized with C. auris identified through active surveillance/screening by NYS Department of Health. "Colonized/screened" individuals were old (median age, 74 year), had extensive health care exposures and underlying conditions (multiple health care facility admissions in the 90 days prior with more than 80% requiring mechanical ventilation), and had 30- and 90-day mortality rates of 17.5% and 37.7%, respectively (with approximately 60% expired in the 2-year follow-up period). This description is helpful to inform additional prevention measures and add to the collective understanding of C. auris in the United States.


Assuntos
Candida auris , Candida , Idoso , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Hospitalização , Humanos , New York/epidemiologia , Estados Unidos
15.
Front Microbiol ; 12: 757835, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34691009

RESUMO

The recognition of a new yeast, Candida auris, in 2009 in East Asia, and its rapid global spread, was a reminder of the threats posed by multidrug-resistant fungal pathogens. C. auris had likely remained unrecognized for a long time as accurate tests were not available. The laboratory community responded to the C. auris challenge by publishing 35 new or revised diagnostic methods between 2014 and early 2021. The commercial sector also modified existing diagnostic devices. These C. auris diagnostic tests run the gamut from traditional culture-based differential and selective media, biochemical assimilations, and rapid protein profiles, as well as culture-independent DNA-based diagnostics. We provide an overview of these developments, especially the tests with validation data that were subsequently adopted for common use. We share a workflow developed in our laboratory to process over 37,000 C. auris surveillance samples and 5,000 C. auris isolates from the outbreak in the New York metropolitan area. Our preview covers new devices and diagnostic approaches on the horizon based on microfluidics, optics, and nanotechnology. Frontline laboratories need rapid, cheap, stable, and easy-to-implement tests to improve C. auris diagnosis, surveillance, patient isolation, admission screening, and environmental control. Among the urgent needs is a lateral flow assay or similar device for presumptive C. auris identification. All laboratories will benefit from devices that allow rapid antifungal susceptibility testing, including detection of mutations conferring drug resistance. Hopefully, multiplex test panels are on the horizon for synergy of C. auris testing with ongoing surveillance of other healthcare-associated infections. C. auris genome analysis has a proven role for outbreak investigations, and diagnostic laboratories need quick access to regional and national genome analysis networks.

16.
Ann Intern Med ; 174(11): 1554-1562, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34487450

RESUMO

BACKGROUND: Candida auris, a multidrug-resistant yeast, can spread rapidly in ventilator-capable skilled-nursing facilities (vSNFs) and long-term acute care hospitals (LTACHs). In 2018, a laboratory serving LTACHs in southern California began identifying species of Candida that were detected in urine specimens to enhance surveillance of C auris, and C auris was identified in February 2019 in a patient in an Orange County (OC), California, LTACH. Further investigation identified C auris at 3 associated facilities. OBJECTIVE: To assess the prevalence of C auris and infection prevention and control (IPC) practices in LTACHs and vSNFs in OC. DESIGN: Point prevalence surveys (PPSs), postdischarge testing for C auris detection, and assessments of IPC were done from March to October 2019. SETTING: All LTACHs (n = 3) and vSNFs (n = 14) serving adult patients in OC. PARTICIPANTS: Current or recent patients in LTACHs and vSNFs in OC. INTERVENTION: In facilities where C auris was detected, PPSs were repeated every 2 weeks. Ongoing IPC support was provided. MEASUREMENTS: Antifungal susceptibility testing and whole-genome sequencing to assess isolate relatedness. RESULTS: Initial PPSs at 17 facilities identified 44 additional patients with C auris in 3 (100%) LTACHs and 6 (43%) vSNFs, with the first bloodstream infection reported in May 2019. By October 2019, a total of 182 patients with C auris were identified by serial PPSs and discharge testing. Of 81 isolates that were sequenced, all were clade III and highly related. Assessments of IPC identified gaps in hand hygiene, transmission-based precautions, and environmental cleaning. The outbreak was contained to 2 facilities by October 2019. LIMITATION: Acute care hospitals were not assessed, and IPC improvements over time could not be rigorously evaluated. CONCLUSION: Enhanced laboratory surveillance and prompt investigation with IPC support enabled swift identification and containment of C auris. PRIMARY FUNDING SOURCE: Centers for Disease Control and Prevention.


Assuntos
Candidíase/diagnóstico , Candidíase/prevenção & controle , Cuidados Semi-Intensivos , Adulto , Idoso , Idoso de 80 Anos ou mais , California/epidemiologia , Candida auris/genética , Candidíase/transmissão , Feminino , Humanos , Controle de Infecções , Assistência de Longa Duração , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Alta do Paciente , Instituições de Cuidados Especializados de Enfermagem , Sequenciamento Completo do Genoma
17.
PLoS Negl Trop Dis ; 15(9): e0009765, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34529679

RESUMO

Coccidioidomycosis (Valley fever) is a pulmonary and systemic fungal disease with increasing incidence and expanding endemic areas. The differentiation of etiologic agents Coccidioides immitis and C. posadasii remains problematic in the clinical laboratories as conventional PCR and satellite typing schemes are not facile. Therefore, we developed Cy5- and FAM-labeled TaqMan-probes for duplex real-time PCR assay for rapid differentiation of C. immitis and C. posadasii from culture and clinical specimens. The RRA2 gene encoding proline-rich antigen 2, specific for Coccidioides genus, was the source for the first set of primers and probe. Coccidioides immitis contig 2.2 (GenBank: AAEC02000002.1) was used to design the second set of primers and probe. The second primers/probe did not amplify the corresponding C. posadasii DNA, because of an 86-bp deletion in the contig. The assay was highly sensitive with limit of detection of 0.1 pg gDNA/PCR reaction, which was equivalent to approximately ten genome copies of C. immitis or C. posadasii. The assay was highly specific with no cross-reactivity to the wide range of fungal and bacterial pathogens. Retrospective analysis of fungal isolates and primary specimens submitted from 1995 to 2020 confirmed 168 isolates and four primary specimens as C. posadasii and 30 isolates as C. immitis from human coccidioidomycosis cases, while all eight primary samples from two animals (rhesus monkey and rhinoceros) were confirmed as C. posadasii. A preliminary analysis of cerebrospinal fluid (CSF) and pleural fluid samples showed positive correlation between serology tests and real-time PCR for two of the 15 samples. The Coccidioides spp. duplex real-time PCR will allow rapid differentiation of C. immitis and C. posadasii from clinical specimens and further augment the treatment and surveillance of coccidioidomycosis.


Assuntos
Coccidioides/classificação , Coccidioidomicose/diagnóstico , Coccidioidomicose/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sequência de Bases , Coccidioidomicose/epidemiologia , DNA Fúngico/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Especificidade da Espécie
18.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33397721

RESUMO

Self-splicing proteins, called inteins, are present in many human pathogens, including the emerging fungal threats Cryptococcus neoformans (Cne) and Cryptococcus gattii (Cga), the causative agents of cryptococcosis. Inhibition of protein splicing in Cryptococcus sp. interferes with activity of the only intein-containing protein, Prp8, an essential intron splicing factor. Here, we screened a small-molecule library to find addititonal, potent inhibitors of the Cne Prp8 intein using a split-GFP splicing assay. This revealed the compound 6G-318S, with IC50 values in the low micromolar range in the split-GFP assay and in a complementary split-luciferase system. A fluoride derivative of the compound 6G-318S displayed improved cytotoxicity in human lung carcinoma cells, although there was a slight reduction in the inhibition of splicing. 6G-318S and its derivative inhibited splicing of the Cne Prp8 intein in vivo in Escherichia coli and in C. neoformans Moreover, the compounds repressed growth of WT C. neoformans and C. gattii In contrast, the inhibitors were less potent at inhibiting growth of the inteinless Candida albicans Drug resistance was observed when the Prp8 intein was overexpressed in C. neoformans, indicating specificity of this molecule toward the target. No off-target activity was observed, such as inhibition of serine/cysteine proteases. The inhibitors bound covalently to the Prp8 intein and binding was reduced when the active-site residue Cys1 was mutated. 6G-318S showed a synergistic effect with amphotericin B and additive to indifferent effects with a few other clinically used antimycotics. Overall, the identification of these small-molecule intein-splicing inhibitors opens up prospects for a new class of antifungals.


Assuntos
Processamento de Proteína/fisiologia , Proteínas de Ligação a RNA/genética , Antifúngicos/farmacologia , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Cryptococcus neoformans/patogenicidade , Proteínas Fúngicas/metabolismo , Humanos , Inteínas/genética , Íntrons/genética , Processamento de Proteína/genética , Splicing de RNA/genética , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência/métodos
19.
Open Forum Infect Dis ; 8(1): ofaa620, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33511238

RESUMO

BACKGROUND: Patients colonized with multidrug-resistant Candida auris and discharged to a community setting can subsequently seek care in a different healthcare facility and might be a source of nosocomial transmission of C auris. METHODS: We designed a case management pilot program for a cohort of New York City residents who had a history of positive C auris culture identified during clinical or screening activities in healthcare settings and discharged to a community setting during 2017-2019. Approximately every 3 months, case managers coordinated C auris colonization assessments, which included swabs of groin, axilla, and body sites yielding C auris previously. Patients eligible to become serially negative were those with ≥2 C auris colonization assessments after initial C auris identification. Clinical characteristics of serially negative and positive patients were compared. RESULTS: The cohort included 75 patients. Overall, 45 patients were eligible to become serially negative and had 552 person-months of follow-up. Of these 45 patients, 28 patients were serially negative (62%; rate 5.1/100 person-months), 8 were serially positive, and 9 could not be classified as either. There were no clinical characteristics that were significantly different between serially negative and positive patients. The median time from initial C auris identification to being serially negative at assessments was 8.6 months (interquartile range, 5.7-10.8 months). CONCLUSIONS: A majority of patients, assessed at least twice after C auris identification, no longer had C auris detectable on serial colonization assessments.

20.
J Clin Microbiol ; 59(3)2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33298609

RESUMO

Blastomycosis due to Blastomyces dermatitidis and Blastomyces gilchristii is a significant cause of respiratory mycoses in North America with occasional reported outbreaks. We developed a highly sensitive, specific, and reproducible TaqMan duplex real-time PCR assay for the differentiation of B. dermatitidis and B. gilchristii The new assay permitted retrospective analysis of Blastomyces cultures (2005 to 2019) and primary clinical specimens from blastomycosis cases (2013 to 2019) from New York patients. We identified B. dermatitidis as the predominant pathogen in 38 cases of blastomycosis, while B. gilchristii was a minor pathogen involved in five cases; these findings expand understanding of blastomycosis in New York. The duplex real-time PCR assay could be implemented in reference and public health laboratories to further understand the ecology and epidemiology of blastomycosis due to B. dermatitidis and B. gilchristii.


Assuntos
Blastomyces , Blastomicose , Blastomyces/genética , Blastomicose/diagnóstico , Blastomicose/epidemiologia , Humanos , New York/epidemiologia , América do Norte , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos
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