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1.
J Clin Microbiol ; 62(4): e0142823, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38470023

RESUMO

The molecular detection of Toxoplasma gondii DNA is a key tool for the diagnosis of disseminated and congenital toxoplasmosis. This multicentric study from the Molecular Biology Pole of the French National Reference Center for toxoplasmosis aimed to evaluate Toxoplasma gondii Real-TM PCR kit (Sacace). The study compared the analytical and clinical performances of this PCR assay with the reference PCRs used in proficient laboratories. PCR efficiencies varied from 90% to 112%; linearity zone extended over four log units (R2 > 0.99) and limit of detection varied from 0.01 to ≤1 Tg/mL depending on the center. Determined on 173 cryopreserved DNAs from a large range of clinical specimens, clinical sensitivity was 100% [106/106; 95 confidence interval (CI): 96.5%-100%] and specificity was 100% (67/67; 95 CI: 94.6%-100%). The study revealed two potential limitations of the Sacace PCR assay: the first was the inconsistency of the internal control (IC) when added to the PCR mixture. This point was not found under routine conditions when the IC was added during the extraction step. The second is a lack of practicality, as the mixture is distributed over several vials, requiring numerous pipetting operations. Overall, this study provides useful information for the molecular diagnosis of toxoplasmosis; the analytical and clinical performances of the Sacace PCR kit were satisfactory, the kit having sensitivity and specificity similar to those of expert center methods and being able to detect low parasite loads, at levels where multiplicative analysis gives inconsistently positive results. Finally, the study recommends multiplicative analysis in particular for amniotic fluids, aqueous humor, and other single specimens.


Assuntos
Toxoplasma , Toxoplasmose Congênita , Toxoplasmose , Humanos , Toxoplasma/genética , Toxoplasmose/diagnóstico , Toxoplasmose/parasitologia , Toxoplasmose Congênita/diagnóstico , Toxoplasmose Congênita/parasitologia , DNA , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , DNA de Protozoário/genética , DNA de Protozoário/análise
2.
Mycopathologia ; 188(1-2): 169-171, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36287321

RESUMO

Candida palmioleophila belongs to the Saccharomycetales. This opportunistic yeast which has been associated with invasive infections in human and animals, warrants a specific attention as it is frequently misidentified and display reduced susceptibility to fluconazole. Here, we report the first draft genome of C. palmioleophila, obtained from a clinical isolate.


Assuntos
Candida , Fluconazol , Animais , Humanos , Fluconazol/farmacologia , Candida/genética , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Saccharomyces cerevisiae , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica
3.
J Infect Dis ; 225(5): 868-880, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34604908

RESUMO

BACKGROUND: The role of respiratory coinfections at diagnosis of Pneumocystis jirovecii pneumonia (PcP) on clinical impact has been underestimated. METHODS: A retrospective observational study was conducted January 2011 to April 2019 to evaluate respiratory coinfections at diagnosis of PcP patients in 2 tertiary care hospitals. Coinfection was defined by identification of pathogens from P. jirovecii-positive samples. RESULTS: Of 7882 respiratory samples tested for P. jirovecii during the 8-year study, 328 patients with diagnosis of PcP were included. Mean age was 56.7 (SD 14.9) years, 193 (58.8%) were male, 74 (22.6%) had positive HIV serology, 125 (38.1%) had viral coinfection, 76 (23.2%) bacterial coinfection, and 90-day mortality was 25.3%. In the overall population, 90-day mortality was independently associated with solid tumor underlying disease (odds ratio [OR], 11.8; 95% confidence interval [CI], 1.90-78.0; P = .008), sepsis-related organ failure assessment score (SOFA) at admission (OR, 1.62; 95% CI, 1.34-2.05; P< .001), and cytomegalovirus (CMV) respiratory coinfection (OR, 3.44; 95% CI, 1.24-2.90; P = .02). Among HIV-negative patients, respiratory CMV coinfection was associated with worse prognosis, especially when treated with adjunctive corticosteroid therapy. CONCLUSIONS: Respiratory CMV coinfection at PcP diagnosis was independently associated with increased 90-day mortality, specifically in HIV-negative patients.


Assuntos
Coinfecção , Infecções por Citomegalovirus , Infecções por HIV , Pneumocystis carinii , Pneumonia por Pneumocystis , Citomegalovirus , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia por Pneumocystis/complicações , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/epidemiologia , Estudos Retrospectivos
4.
Clin Infect Dis ; 75(7): 1242-1244, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-35213688

RESUMO

A returned traveler to Uganda presented with a Plasmodium falciparum kelch13 A675V mutant infection that exhibited delayed clearance under artesunate therapy. Parasites were genetically related to recently reported Ugandan artemisinin-resistant A675V parasites. Adequate malaria prevention measures and clinical and genotypic surveillance are important tools to avoid and track artemisinin resistance.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Artesunato/uso terapêutico , Resistência a Medicamentos/genética , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Plasmodium falciparum/genética , Proteínas de Protozoários , Uganda
5.
Med Mycol ; 60(7)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35713494

RESUMO

Aspergillosis is pervasive in bird populations, especially those under human care. Its management can be critically impacted by exposure to high levels of conidia and by resistance to azole drugs. The fungal contamination in the environment of a Humboldt penguin (Spheniscus humboldti) group, housed in a French zoological park next to numerous large crop fields, was assessed through three serial sessions of surface sampling in nests, in 2018-20: all isolates were counted and characterized by sequencing. When identified as Aspergillus fumigatus, they were systematically screened for resistance mutations in the cyp51A gene and tested for minimal inhibitory concentrations (MICs) determination. At the same time, the clinical incidence of aspergillosis was evaluated in the penguin population by the means of systematic necropsy and mycological investigations. A microsatellite-based analysis tracked the circulation of A. fumigatus strains. Environmental investigations highlighted the substantial increase of the fungal load during the summer season (>12-fold vs. the other timepoints) and a large overrepresentation of species belonging to the Aspergillus section Fumigati, ranging from 22.7 to 94.6% relative prevalence. Only one cryptic species was detected (A. nishimurae), and one isolate exhibited G138S resistance mutation with elevated MICs. The overall incidence of aspergillosis was measured at ∼3.4% case-years, and mostly in juveniles. The analysis of microsatellite polymorphism revealed a high level of genetic diversity among A. fumigatus clinical isolates. In contrast, one environmental strain appeared largely overrepresented during the summer sampling session. In all, the rural location of the zoo did not influence the emergence of resistant strains.


Assuntos
Aspergilose , Spheniscidae , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergilose/microbiologia , Aspergilose/veterinária , Aspergillus fumigatus , Azóis/farmacologia , Farmacorresistência Fúngica , Proteínas Fúngicas/genética , Humanos , Programas de Assistência Gerenciada , Testes de Sensibilidade Microbiana/veterinária , Mutação
6.
Mycoses ; 65(3): 303-311, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34821412

RESUMO

Candida and Cryptococcus affect millions of people yearly, being responsible for a wide array of clinical presentations, including life-threatening diseases. Interestingly, most human pathogenic yeasts are not restricted to the clinical setting, as they are also ubiquitous in the environment. Recent studies raise concern regarding the potential impact of agricultural use of azoles on resistance to medical antifungals in yeasts, as previously outlined with Aspergillus fumigatus. Thus, we undertook a narrative review of the literature and provide lines of evidence suggesting that an alternative, environmental route of azole resistance, may develop in pathogenic yeasts, in addition to patient route. However, it warrants sound evidence to support that pathogenic yeasts cross border between plants, animals and humans and that environmental reservoirs may contribute to azole resistance in Candida or other yeasts for humans. As these possibilities could concern public health, we propose a road map for future studies under the One Health perspective.


Assuntos
Fungicidas Industriais , Saúde Única , Animais , Antifúngicos/farmacologia , Aspergillus fumigatus , Azóis/farmacologia , Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Humanos , Testes de Sensibilidade Microbiana
7.
Acta Paediatr ; 110(1): 79-84, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32304593

RESUMO

AIM: We assessed the diagnostic accuracy of serum (1 â†’ 3)-ß-D-glucan (BDG) for neonatal invasive candidiasis (NIC) using the recommended cut-off usually used in adults for detecting invasive candidiasis and searched for an optimal cut-off for ruling out NIC. METHODS: We conducted a prospective cross-sectional study at Nantes University medical centre from January 2017 to July 2018. All consecutive newborn infants of less than 28 days of corrected age, with clinically suspected NIC, who underwent BDG assay, were included. Sensitivity and specificity were calculated by using the recommended cut-off of 80 pg/mL. Receiver operating characteristic curve analysis was used to identify an optimal cut-off value. RESULTS: We included 55 newborn infants with 61 episodes of suspected NIC. Their median gestational and chronological ages were 28.0 weeks (interquartile range [IQR] 26.4-34.1) and 10.0 days (IQR 6.0-22.0), respectively. Of 61 episodes, seven revealed NIC. Sensitivity and specificity were 85.7% (95% confidence interval [CI] 42.1%-99.6%) and 51.9% (37.8%-65.7%) with the recommended cut-off, respectively. An optimal cut-off of 174 pg/mL offered the same sensitivity but higher specificity 77.8% (64.4%-88.0%). CONCLUSION: The recommended cut-off of 80 pg/mL was probably too low for ruling out NIC. A higher cut-off might have been more appropriate.


Assuntos
Candidíase Invasiva , beta-Glucanas , Adulto , Candidíase Invasiva/diagnóstico , Estudos Transversais , Humanos , Lactente , Recém-Nascido , Estudos Prospectivos , Sensibilidade e Especificidade
8.
BMC Infect Dis ; 20(1): 945, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33308180

RESUMO

BACKGROUND: Filamentous basidiomycetes are mainly considered to be respiratory tract colonizers but the clinical significance of their isolation in a specimen is debatable. Hormographiella aspergillata was first reported as a human pathogen in 1971. We discuss the role of this mold as a pathogen or colonizer and give an update on diagnostic tools and in vitro antifungal susceptibility. CASE PRESENTATION: We identified three cases of H. aspergillata with respiratory symptoms in a short period of time. One invasive infection and two colonizations were diagnosed. Culture supernatants showed that H. aspergillata can produce galactomannan and ß-D-glucan but not glucuronoxylomannan. For the first time, isavuconazole susceptibility was determined and high minimum inhibitory concentrations (MICs) were found. Liposomal amphotericin B and voriconazole have the lowest MICs. CONCLUSION: To date, 22 invasive infections involving H. aspergillata have been reported. On isolation of H. aspergillata, its pathogenic potential in clinical settings can be tricky. Molecular identification and antifungal susceptibility testing are essential considering high resistance against several antifungal therapies.


Assuntos
Agaricales/genética , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Pneumopatias Fúngicas/diagnóstico , Adulto , Agaricales/isolamento & purificação , Idoso , Evolução Fatal , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Prenat Diagn ; 40(13): 1741-1752, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32506432

RESUMO

OBJECTIVE: To describe the lesions detected by prenatal ultrasound examination in congenital toxoplasmosis (CT). METHODS: We retrospectively analyzed all cases of fetal infection with Toxoplasma gondii with ultrasound anomalies described by fetal medicine experts in 2009 to 2019 in 30 French centers. RESULTS: Eighty-eight cases of CT were included. Forty-five (51.1%) had one or more cerebral signs only, 35 (39.8%) had cerebral plus extracerebral signs and 8 (9.1%) had extracerebral signs only. The main cerebral signs were intracranial hyperechogenic nodular foci (n = 60) of which 20 were isolated, ventriculomegalies (n = 44) which generally increased during follow-up, and periventricular abscesses (n = 12). The main extracerebral signs were hepatomegaly and/or splenomegaly (n = 14), small for gestational age (n = 14), ascites (n = 14, including 2 with hydrops), and hyperechogenic bowel (n = 11). Maternal infection occurred mostly in the first or second trimester (81 cases), periconceptionally in one and in the third trimester in six cases. The first ultrasound signs were detected after a median of 7 weeks (range: 1.4; 24.0) following maternal toxoplasmosis seroconversion. CONCLUSION: While no sign was specific of CT, there were typical associations of cerebral signs with or without extracerebral signs. Detailed ultrasound examination could improve prognostic evaluation, as well as diagnosis of CT in settings lacking serological screening.


Assuntos
Doenças Fetais/diagnóstico por imagem , Complicações Infecciosas na Gravidez/diagnóstico por imagem , Toxoplasmose Congênita/diagnóstico por imagem , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Estudos Retrospectivos
10.
Mycoses ; 61(1): 30-34, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28922487

RESUMO

Fungal rhinosinusitis (FRS) has a worldwide distribution, comprises distinct clinical entities but is mostly due to Aspergillus among which Aspergillus fumigatus plays a major role in European countries. Although, there is accumulating evidence for the emergence of environmentally acquired-azole resistance in A. fumigatus (such as TR34 /L98H) in various clinical settings, there is few data for patients with FRS. In this study, we aimed to investigate the prevalence of A. fumigatus azole resistance due to TR34 /L98H in a multicentre cohort of patients with FRS. One hundred and thirty-seven patients with FRS admitted between 2002 and 2016 at four French medical centres were retrospectively enrolled. Clinical and mycological findings were collected. Aspergillus fumigatus and the TR34 /L98H alteration conferring azole resistance were investigated directly from clinical samples using the commercial CE-IVD marked MycoGENIE® A. fumigatus real-time PCR assay. Fungal ball was the more frequent clinical form (n = 118). Despite the presence of fungal hyphae at direct microscopic examination, mycological cultures remained negative for 83 out of the 137 patients (60.6%). The PCR assay proved to be useful allowing the identification of A. fumigatus and etiological diagnosis in 106 patients (77.4%) compared with 44 patients (32.1%) when using culture as the reference method. Importantly, neither TR34 nor L98H alterations were evidenced.


Assuntos
Aspergilose/diagnóstico , Aspergillus fumigatus/genética , Azóis/farmacologia , Farmacorresistência Fúngica/genética , Rinite/microbiologia , Sinusite/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/farmacologia , Aspergilose/epidemiologia , Aspergilose/microbiologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/isolamento & purificação , Aspergillus fumigatus/ultraestrutura , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Humanos , Hifas/ultraestrutura , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Adulto Jovem
11.
Clin Infect Dis ; 64(1): 76-78, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27682064

RESUMO

A case of fatal aspergillosis due to a TR46/Y121F/T289A azole-resistant Aspergillus fumigatus is reported. Environmental investigations at the patient's residence led to the recovery of TR46/Y121F/T289A isolates, genotypically indistinguishable from the clinical isolate, supporting for the first time the direct role of household as potential source of azole-resistant invasive aspergillosis.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/etiologia , Aspergillus fumigatus/efeitos dos fármacos , Azóis/uso terapêutico , Farmacorresistência Fúngica , Hospedeiro Imunocomprometido , Idoso , Antifúngicos/farmacologia , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Aspergillus fumigatus/genética , Azóis/farmacologia , Sistema Enzimático do Citocromo P-450/genética , Evolução Fatal , Proteínas Fúngicas/genética , Humanos , Infliximab/efeitos adversos , Infliximab/uso terapêutico , Testes de Sensibilidade Microbiana , Mutação
12.
Antimicrob Agents Chemother ; 59(7): 4331-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25918139

RESUMO

Azole resistance in Aspergillus fumigatus is an emerging public health concern. Recently, a novel fungicide-driven mutation in the cyp51A gene and its promoter, TR46/Y121F/T289A, leading to high-level resistance to voriconazole has been identified in The Netherlands, Belgium, Germany, Denmark, Tanzania, and India in both clinical and environmental samples. Here we report the first description of A. fumigatus carrying this mutation in France, in a cystic fibrosis patient, underlining the need for extensive monitoring of Aspergillus resistance.


Assuntos
Antibacterianos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Azóis/farmacologia , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Anticorpos Antifúngicos/análise , Aspergilose/microbiologia , Fibrose Cística/microbiologia , Europa (Continente) , França , Humanos , Imunoglobulina E/análise , Itraconazol/farmacologia , Masculino , Mutação/genética , Estudos Retrospectivos , Voriconazol/farmacologia , Adulto Jovem
13.
Int J Med Microbiol ; 304(8): 1062-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25201327

RESUMO

In South America, disseminated histoplasmosis due to Histoplasma capsulatum var. capsulatum (H. capsulatum), is a severe and frequent opportunistic infection in AIDS patients. In areas outside the USA where specific-Histoplasma antigen detection is not available, the diagnosis is difficult. With the galactomannan antigen (GM) detection, a test commonly used for invasive aspergillosis diagnosis, there is a cross-reactivity with H. capsulatum that can be helpful for the diagnosis of histoplasmosis. The aim of this study was to evaluate the GM detection for the diagnosis of disseminated histoplasmosis in AIDS patients. The performance of the GM detection was evaluated with serum collected in French Guiana where H. capsulatum is highly endemic. Sera from AIDS patients with disseminated histoplasmosis occurring from 2002 to 2009 and from control HIV-positive patients without histoplasmosis were tested with the GM detection and Histoplasma-specific antibody detection (IEP). In 39 AIDS patients with proven disseminated histoplasmosis, the sensitivity of the Histoplasma IEP was only 35.9% and was linked to the TCD4+ lymphocyte level. For the GM detection, the sensitivity (Se) was 76.9% and specificity (Sp) was 100% with the recommended threshold for aspergillosis diagnosis (0.5). The test was more efficient with a threshold of 0.4 (Se: 0.82 [95% CI: 0.66-0.92], Sp: 1.00 [95% CI: 0.86-1.00], LR+: >10, LR-: 0.18). This study confirms that the GM detection can be a surrogate marker for the diagnosis of disseminated histoplasmosis in AIDS patients in endemic areas where Histoplasma EIA is not available.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/complicações , Histoplasma/isolamento & purificação , Histoplasmose/diagnóstico , Histoplasmose/tratamento farmacológico , Mananas/sangue , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Adulto , Anticorpos Antifúngicos/sangue , Estudos de Coortes , Feminino , Guiana Francesa , Galactose/análogos & derivados , Histoplasmose/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , América do Sul
14.
Chest ; 165(6): 1319-1329, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38215935

RESUMO

BACKGROUND: Pneumocystis jirovecii pneumonia (PcP) remains associated with high rates of mortality, and the impact of immunocompromising underlying disease on the clinical presentation, severity, and mortality of PcP has not been adequately evaluated. RESEARCH QUESTION: Does the underlying disease and immunosuppression causing PcP impact the outcome and clinical presentation of the disease? STUDY DESIGN AND METHODS: In this multicenter retrospective observational study, conducted from January 2011 to December 2021, all consecutive patients admitted with a proven or probable diagnosis of PcP according to the European Organisation for Research and Treatment of Cancer consensus definitions were included to assess the epidemiology and impact of underlying immunosuppressive diseases on overall and 90-day mortality. RESULTS: Overall, 481 patients were included in the study; 180 (37.4%) were defined as proven PcP and 301 (62.6%) were defined as probable PcP. Patients with immune-mediated inflammatory diseases (IMIDs) or solid tumors had a statistically poorer prognosis than other patients with PcP at day 90. In multivariate analysis, among the HIV-negative population, solid tumor underlying disease (OR, 5.47; 95% CI, 2.16-14.1; P < .001), IMIDs (OR, 2.19; 95% CI, 1.05-4.60; P = .037), long-term corticosteroid exposure (OR, 2.07; 95% CI, 1.03-4.31; P = .045), cysts in sputum/BAL smears (OR, 1.92; 95% CI, 1.02-3.62; P = .043), and SOFA score at admission (OR, 1.58; 95% CI, 1.39-1.82; P < .001) were independently associated with 90-day mortality. Prior corticotherapy was the only immunosuppressant associated with 90-day mortality (OR, 1.67; 95% CI, 1.03-2.71; P = .035), especially for a prednisone daily dose ≥ 10 mg (OR, 1.80; 95% CI, 1.14-2.85; P = .010). INTERPRETATION: Among patients who were HIV-negative, long-term corticosteroid prior to PcP diagnosis was independently associated with increased 90-day mortality, specifically in patients with IMIDs. These results highlight both the needs for PcP prophylaxis in patients with IMIDs and to early consider PcP curative treatment in severe pneumonia among patients with IMIDs.


Assuntos
Pneumocystis carinii , Pneumonia por Pneumocystis , Humanos , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/epidemiologia , Pneumonia por Pneumocystis/mortalidade , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Prognóstico , Idoso , Pneumocystis carinii/isolamento & purificação , Hospedeiro Imunocomprometido , Fatores de Risco
15.
PLoS Pathog ; 7(9): e1002254, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21949655

RESUMO

CD36 is the major receptor mediating nonopsonic phagocytosis of Plasmodium falciparum-parasitized erythrocytes by macrophages. Its expression on macrophages is mainly controlled by the nuclear receptor PPARγ. Here, we demonstrate that inflammatory processes negatively regulate CD36 expression on human and murine macrophages, and hence decrease Plasmodium clearance directly favoring the worsening of malaria infection. This CD36 downregulation in inflammatory conditions is associated with a failure in the expression and activation of PPARγ. Interestingly, using siRNA mediating knock down of Nrf2 in macrophages or Nrf2- and PPARγ-deficient macrophages, we establish that in inflammatory conditions, the Nrf2 transcription factor controls CD36 expression independently of PPARγ. In these conditions, Nrf2 activators, but not PPARγ ligands, enhance CD36 expression and CD36-mediated Plasmodium phagocytosis. These results were confirmed in human macrophages and in vivo where only Nrf2 activators improve the outcome of severe malaria. Collectively, this report highlights that the Nrf2 transcription factor could be an alternative target to PPARγ in the control of severe malaria through parasite clearance.


Assuntos
Antígenos CD36/biossíntese , Macrófagos/imunologia , Malária Falciparum/imunologia , Fator 2 Relacionado a NF-E2/metabolismo , Fagocitose , Plasmodium falciparum/imunologia , Animais , Regulação para Baixo , Eritrócitos/parasitologia , Feminino , Humanos , Macrófagos/metabolismo , Macrófagos/parasitologia , Malária Falciparum/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2/genética , PPAR gama/genética , PPAR gama/metabolismo , Plasmodium falciparum/metabolismo
16.
Med Mycol ; 51(6): 652-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23373445

RESUMO

Candida spp. are an important cause of nosocomial bloodstream infections. Currently, complete identification of yeasts with conventional methods takes several days. We report here the first evaluation of an extraction method associated with the Vitek MS matrix-assisted laser desorption ionization time of flight mass spectrometry for direct identification of Candida species from positive blood cultures. We evaluated this protocol with blood cultures that were inoculated with reference and routine isolates (eight reference strains, 30 patients isolates and six mixed cultures containing two strains of different Candida species), or from patients with candidemia (28 isolates). This method performed extremely well (97% correct identification) with blood cultures of single Candida spp. and significantly reduced the time of diagnosis. Nevertheless, subculture remains indispensable to test fungal resistance and to detect mixed infections.


Assuntos
Candida/química , Candida/classificação , Candidemia/diagnóstico , Técnicas Microbiológicas/métodos , Micologia/métodos , Manejo de Espécimes/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sangue/microbiologia , Candida/isolamento & purificação , Humanos , Sensibilidade e Especificidade , Fatores de Tempo
17.
Microbiol Resour Announc ; 12(4): e0126022, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36861993

RESUMO

Yarrowia lipolytica is a nonconventional yeast of industrial interest that can sometimes act as an opportunistic pathogen and is responsible for invasive fungal infections. We report the draft genome sequence of the fluconazole-resistant strain CBS 18115, which was isolated from a blood culture. The Y132F substitution in ERG11, which was previously described in fluconazole-resistant Candida isolates, was identified.

18.
Clin Microbiol Infect ; 29(2): 257.e7-257.e11, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36209989

RESUMO

OBJECTIVES: Diutina (Candida) catenulata is an ascomycetous yeast isolated from environmental sources and animals, occasionally infecting humans. The aim of this study is to shed light on the in vitro antifungal susceptibility and genetic diversity of this opportunistic yeast. METHODS: Forty-five D. catenulata strains isolated from various sources (including human and environmental sources) and originating from nine countries were included. Species identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and confirmed via internal transcribed spacer ribosomal DNA barcoding. In vitro antifungal susceptibility was determined for seven systemic antifungals via the gradient strip method after 48 hours of incubation at 35°C using Etest® (Biomérieux) or Liofilchem® strips. Isolates exhibiting fluconazole minimal inhibitory concentrations (MICs) of ≥8 µg/mL were investigated for mutations in the ERG11 gene. A novel microsatellite genotyping scheme consisting of four markers was developed to assess genetic diversity. RESULTS: MIC ranges for amphotericin B, caspofungin, micafungin, isavuconazole, and posaconazole were 0.19-1 µg/mL, 0.094-0.5 µg/mL, 0.012-0.064 µg/mL, 0.003-0.047 µg/mL, and 0.006-0.032 µg/mL, respectively. By comparison, a broad range of MICs was noted for fluconazole (0.75 to >256 µg/mL) and voriconazole (0.012-0.38 mg/L), the higher values being observed among clinical strains. The Y132F amino acid substitution, associated with azole resistance in various Candida species (C. albicans, C. tropicalis, C. parapsilosis, and C. orthopsilosis), was the main substitution identified. Although microsatellite typing showed extensive genetic diversity, most strains with high fluconazole MICs clustered together, suggesting human-to-human transmission or a common source of contamination. DISCUSSION: The high rate of acquired fluconazole resistance among clinical isolates of D. catenulata is of concern. In this study, we highlight a link between the genetic diversity of D. catenulata and its antifungal resistance patterns, suggesting possible clonal transmission of resistant isolates.


Assuntos
Antifúngicos , Fluconazol , Animais , Humanos , Fluconazol/farmacologia , Antifúngicos/farmacologia , Candida , Anfotericina B/farmacologia , Voriconazol , Leveduras , Candida parapsilosis , Candida tropicalis , DNA Intergênico , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica/genética
19.
J Clin Microbiol ; 50(6): 2107-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22495559

RESUMO

We report here a clinical evaluation of the Vitek MS system for rapid fungal identification. A strategy that uses a single deposit without prior protein extraction was utilized to save time and money. Clinical isolates from the Toulouse University hospital were used to evaluate the performance of the Vitek MS compared to that of both routine laboratory techniques and Vitek2. The Vitek MS performed well in the identification of yeasts and Aspergillus fungi (93.2% of correct identifications).


Assuntos
Fungos/química , Fungos/classificação , Técnicas Microbiológicas/métodos , Micologia/métodos , Micoses/diagnóstico , Micoses/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Fatores de Tempo
20.
Microorganisms ; 10(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35056552

RESUMO

BACKGROUND: Sterols are the main components of fungal membranes. Inhibiting their biosynthesis is the mode of action of azole antifungal drugs that are widely used to treat fungal disease including aspergillosis. Azole resistance has emerged as a matter of concern but little is known about sterols biosynthesis in azole resistant Aspergillus fumigatus. METHODS: We explored the sterol composition of 12 A. fumigatus isolates, including nine azole resistant isolates with TR34/L98H, TR46/Y121F/T289A or TR53 alterations in the cyp51A gene and its promoter conferring azole resistance. Modifications in sterol composition were also investigated after exposure to two azole drugs, itraconazole and voriconazole. RESULTS: Overall, under basal conditions, sterol compositions were qualitatively equivalent, whatever the alterations in the target of azole drugs with ergosterol as the main sterol detected. Azole exposure reduced ergosterol composition and the qualitative composition of sterols was similar in both susceptible and resistant isolates. Interestingly TR53 strains behaved differently than other strains. CONCLUSIONS: Elucidating sterol composition in azole-susceptible and resistant isolates is of interest for a better understanding of the mechanism of action of these drugs and the mechanism of resistance of fungi.

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