RESUMEN
Species from Candida parapsilosis complex are frequently found in neonatal candidemia. The antifungal agents to treat this infection are limited and the occurrence of low in vitro susceptibility to echinocandins such as micafungin has been observed. In this context, the chaperone Hsp90 could be a target to reduce resistance. Thus, the objective of this research was to identify isolates from the C. parapsilosis complex and verify the action of Hsp90 inhibitors associated with micafungin. The fungal identification was based on genetic sequencing and mass spectrometry. Minimal inhibitory concentrations were determined by broth microdilution method according to Clinical Laboratory and Standards Institute. The evaluation of the interaction between micafungin with Hsp90 inhibitors was realized using the checkerboard methodology. According to the polyphasic taxonomy, C. parapsilosis sensu stricto was the most frequently identified, followed by C. orthopsilosis and C. metapsilosis, and one isolate of Lodderomyces elongisporus was identified by genetic sequencing. The Hsp90 inhibitor geladanamycin associated with micafungin showed a synergic effect in 31.25% of the isolates, a better result was observed with radicicol, which shows synergic effect in 56.25% tested yeasts. The results obtained demonstrate that blocking Hsp90 could be effective to reduce antifungal resistance to echinocandins.
Asunto(s)
Antifúngicos , Candida parapsilosis , Candidemia , Proteínas HSP90 de Choque Térmico , Micafungina , Humanos , Recién Nacido , Antifúngicos/farmacología , Benzoquinonas/farmacología , Candida parapsilosis/efectos de los fármacos , Candida parapsilosis/aislamiento & purificación , Candida parapsilosis/genética , Candidemia/microbiología , Farmacorresistencia Fúngica , Sinergismo Farmacológico , Equinocandinas/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Proteínas HSP90 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/genética , Lactamas Macrocíclicas/farmacología , Lipopéptidos/farmacología , Micafungina/farmacología , Pruebas de Sensibilidad MicrobianaRESUMEN
Cryptococcus neoformans var. grubii is considered to be the major cause of cryptococcosis in immunosuppressed patients. Understanding cell wall glycoproteins using lectins is of medical interest and can contribute to specific therapy. The aim of this study was to evaluate the carbohydrates on the cell wall of Cryptococcus neoformans var. grubii clinical isolates, using a fluorescein isothiocyanate-lectin binding protocol. Thirty yeast strains stocked in the culture collection were cultivated for 2 days at 30 °C with shaking. Cells were obtained by centrifugation, washed in phosphate-buffered saline, and a suspension of 107 cells/mL was obtained. To determine the binding profile of lectins, concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europaeus agglutinin I (UEA-I), and peanut agglutinin (PNA) conjugated to fluorescein were used. All the tested clinical isolates of Cryptococcus neoformans var. grubii were intensely stained by WGA, moderately stained by Con A, and weakly stained by PNA and UEA-I. Thus, Cryptococcus can be detected in clinical specimens such as blood and cerebrospinal fluid using the fluorescent lectin WGA, which may be considered as an option for detection in cases of suspected cryptococcosis with low laboratory sensitivity. Future applications may be developed using this basic tool.
Asunto(s)
Carbohidratos , Pared Celular/metabolismo , Concanavalina A/metabolismo , Criptococosis/metabolismo , Cryptococcus neoformans/aislamiento & purificación , Cryptococcus neoformans/metabolismo , Lectinas/metabolismo , Criptococosis/microbiología , Criptococosis/patología , HumanosRESUMEN
As the prevalence of drug-resistant Candida isolates continues to rise, the imperative for identifying novel compounds to enhance the arsenal of antifungal drugs becomes increasingly critical. Consequently, exploring new treatment strategies, including synthesizing molecular hybrids and applying combination therapy, is essential. For this reason, this study evaluated the efficacy of ten molecular hybrids of aza-bicyclic 2-isoxazoline-acylhydrazone belonging to two series 90 and 91 as possible anti-Candida agents. In addition, we also investigated the interaction between the hybrids and fluconazole, a commonly used antifungal drug. We evaluated the antifungal effect of aza-bicyclic 2-isoxazoline-acylhydrazone hybrid compounds against six Candida spp. strains that target planktonic cells. However, none of these new molecules were inhibitory active at the tested concentrations (2 to 1,024 µg/mL). Moreover, we analyzed the interaction between the ten new hybrid molecules and fluconazole using the checkerboard assay, employing two different methodologies for reading the plate. For this, one isolate fluconazole-resistant was selected. We observed that only one combination, 6-(4-tert-butylbenzoil)-4,5,6,6a-tetrahydro-3a-H-pirrole[3,2-d]isoxazole-3-carboxylic(furan-2-metilidene)-hydrazide (91e) and fluconazole, exhibited a synergistic interaction (FICI range 0.0781 to 0.4739). The combination successfully inhibited the growth of C. albicans CA2 fluconazole-resistant, and no interaction was observed in an isolate susceptible to fluconazole. Additionally, these results emphasize the continued need for research into new compounds and the importance of using combined approaches to increase their activity.
Asunto(s)
Antifúngicos , Candida albicans , Farmacorresistencia Fúngica , Sinergismo Farmacológico , Fluconazol , Hidrazonas , Isoxazoles , Pruebas de Sensibilidad Microbiana , Antifúngicos/farmacología , Antifúngicos/química , Fluconazol/farmacología , Candida albicans/efectos de los fármacos , Hidrazonas/farmacología , Hidrazonas/química , Isoxazoles/farmacología , Isoxazoles/química , HumanosRESUMEN
Disseminated fusariosis is an uncommon clinical condition in immunocompromised patients. We report a fatal case of disseminated fusariosis secondary to neuroblastoma in a male patient, 15 years old, who underwent a bone marrow transplant. The patient was admitted to the pediatric intensive care unit (PICU) of a public hospital in Recife-PE, Brazil, presenting bone marrow aplasia, severe leukopenia, and thrombocytopenia. After 15 days, the patient developed right knee effusion. Synovial fluid and blood samples were analyzed at the Medical Mycology Laboratory of the Federal University of Pernambuco. Mycological diagnosis was based on the presence of hyaline septate hyphae on direct examination and the isolation of Fusarium oxysporum in culture, confirming the case of disseminated fusariosis. In vitro, the isolate showed fluconazole resistance and sensitivity to amphotericin B, anidulafungin, and voriconazole. Therapy with voriconazole in combination with liposomal amphotericin B led to an improved clinical response; however, due to underlying disease complications, the patient progressed to death.
Asunto(s)
Fusariosis/diagnóstico , Fusariosis/patología , Fusarium/aislamiento & purificación , Neuroblastoma/complicaciones , Adolescente , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Sangre/microbiología , Trasplante de Médula Ósea , Brasil , Resultado Fatal , Humanos , Huésped Inmunocomprometido , Masculino , Pruebas de Sensibilidad Microbiana , Técnicas Microbiológicas , Neuroblastoma/terapia , Líquido Sinovial/microbiologíaRESUMEN
Candidemia is responsible for substantial morbidity and mortality in neonatal intensive care units and represents a challenge due to the complexity of hospitalized neonates, the deficiency in approved and precise diagnostic techniques, and the increasing number of species resistant to antifungal agents. Thus, the objective of this study was to detect candidemia among neonates evaluating the risk factors, epidemiology, and antifungal susceptibility. Blood samples were obtained from neonates with suspected septicemia, and the mycological diagnosis was based on yeast growth in culture. The fungal taxonomy was based on classic identification, automated system, and proteomic, when necessary molecular tools were used. The in vitro susceptibility tests were performed according to the broth microdilution method from Clinical and Laboratory Standards Institute. Statistical analysis was performed using the R software version R-4.2.2. The prevalence of neonatal candidemia was 10.97%. The major risk factors involved were previous use of parenteral nutrition, exposure to broad-spectrum antibiotics, prematurity, and prior use central venous catheter, but only this last was statistically associated with mortality risk. Species from Candida parapsilosis complex and C. albicans were the most frequent. All isolates were susceptible to amphotericin B, except C. haemulonii that also exhibited elevated MICs to fluconazole. C. parapsilosis complex and C. glabrata exhibit the highest MICs to echinocandins. Considering these data, we emphasize that an effective management strategy to reduce the impact of neonatal candidemia should involve the knowledge of risk factors, rapid and precise mycological diagnostic, and tests of antifungal susceptibility to help in the selection of an appropriate treatment.
Asunto(s)
Candidemia , Recién Nacido , Humanos , Candidemia/microbiología , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida , Brasil/epidemiología , Unidades de Cuidado Intensivo Neonatal , Proteómica , Fluconazol , Farmacorresistencia Fúngica , Factores de Riesgo , Candida glabrata , Candida albicans , Candida parapsilosis , Pruebas de Sensibilidad MicrobianaRESUMEN
Premature hospitalized neonates have a greater risk for candidemia, however, fungemia due to rare opportunistic yeasts have been recently reported and is associated with high mortality rates. We herein report the first case in Latin America of Lodderomyces elongisporus fungemia in a premature neonate with a fatal outcome.
Asunto(s)
Candidemia , Fungemia , Enfermedades del Recién Nacido , Saccharomycetales , Recién Nacido , Humanos , Fungemia/diagnóstico , Fungemia/tratamiento farmacológico , América Latina , Saccharomycetales/genética , Candidemia/tratamiento farmacológico , Levaduras , Antifúngicos/farmacología , Antifúngicos/uso terapéuticoRESUMEN
Various researchers have concluded that lectins are useful reagents for the study of fungal cell wall surface glycoconjugates. In this study, we evaluated the expression of N-acetyl-D-glucosamine, L-fucose, D-galactose and glucose/mannose on the cell wall surface of Trichophyton tonsurans and other keratinophilic filamentous fungi, using a simple lectin-binding protocol. The fungal cultures used were isolated from soils obtained from public parks by the hair-bait technique. The lectin assays used concanavalin A (Con A), wheat germ agglutinin (WGA), Ulex europeus agglutinin I (UEA-I) and peanut agglutinin (PNA), all conjugated with horseradish peroxidase. Adhesive tape was placed sticky-side down over the fungal colony, gently pressed and then removed. The fungal-tape samples were incubated with the lectin for 1 h at 4 °C. Lectin binding was visualised using 3,3-diaminobendizine (DAB) and hydrogen peroxidase. There was a high expression of N-acetyl-D-glucosamine on the cell wall surface of all fungi species tested, whereas the expression of L-fucose, D-galactose and glucose/mannose demonstrated inter-specific variations. The lectin-binding assay presented in this article eliminates many of the laborious steps involved in other protocols. The amount and quality of the mycelium and spores immobilised by the adhesive tapes were suitable for obtaining the carbohydrate profile in glycoconjugates of the cell wall surface of filamentous fungi.
Asunto(s)
Pared Celular/química , Hongos/química , Glicoconjugados/análisis , Lectinas/metabolismo , Micología/métodos , Unión Proteica , Microbiología del SueloRESUMEN
Trichosporon species are usually opportunistic pathogens. Here, we present a case of esophagitis caused by T. inkin in a 54-year-old woman with pulmonary cancer and severe neutropenia in whom the susceptibility profile of the isolate against azoles and polyenes was verified. The patient was diagnosed with esophagitis grade I of Wilcox, presenting scattered whitish plaques and exudates in upper two-thirds of the esophageal mucosa. Antifungal therapy involving oral fluconazole (150 mg/day for 14 days) was ineffective. In vitro, the isolate showed no resistance to this azole and sensitivity to amphotericin B. Since T. inkin is of growing importance as an agent of invasive infections in immunocompromised patients, we stress that the diagnosis of esophagitis by this species should be followed by an assessment of the therapeutic sensitivity of the strain involved.
Asunto(s)
Esofagitis/microbiología , Esofagitis/patología , Micosis/diagnóstico , Micosis/patología , Trichosporon/aislamiento & purificación , Antifúngicos/farmacología , Azoles/farmacología , Esofagoscopía , Esófago/microbiología , Esófago/patología , Femenino , Humanos , Huésped Inmunocomprometido , Neoplasias Pulmonares/complicaciones , Pruebas de Sensibilidad Microbiana , Microscopía , Persona de Mediana Edad , Neutropenia/complicaciones , Polienos/farmacología , Insuficiencia del Tratamiento , Trichosporon/efectos de los fármacosRESUMEN
The objective of this study was to evaluate the effects of nanoparticles (nanospheres and nanocapsules) of the promising antifungal 2-amino-thiophene (6CN10) and 6CN10 complexed with 2-hydroxypropyl-ß-cyclodextrin (6CN10:HP-ß-CD) in vitro and compared with free drug against Candida and Cryptococcus, using a microdilution method to measure susceptibility. The Candida and Cryptococcus clinical strains were identified using phenotypic methods and matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF). To measure in vitro antifungal susceptibility, we used microdilution trials. Serial drug or nanoparticle dilutions were prepared according to the CLSI M27-A3 guidelines. Anti-biofilm activity was verified for Cryptococcus neoformans. All Candida isolates were sensitive to the free drug (MIC = 41.66-333.33 µg/mL) and were able to grow even at the higher concentration tested for all 6CN10 nanoparticles. However, the Cryptococcus neoformans strains presented MIC values of 0.32-83.33 µg/mL for 6CN10 nanoparticles, and MIC values of 0.1-0.2 µg/mL for 6CN10:HP-ß-CD nanoparticles, i.e., 3333 times more active than the free drug (MIC values 166.66-333.33 µg/mL), and presenting activity greater than that of the reference drug amphotericin B (MIC = 0.5-0.125 µg/mL). 6CN10:HP-ß-CD nanosphere also showed high anti-biofilm potential. The in vitro study showed that the nanoparticles allowed better drug efficiency against Cryptococcus than did the free drug. These results suggest that 6CN10-loaded nanoparticles may become a future alternative for cryptococcosis and candidiasis therapy. In vivo experiments are essential prior to clinical use.
Asunto(s)
Antifúngicos/farmacología , Hongos/efectos de los fármacos , Nanopartículas/química , Tiofenos/química , Tiofenos/farmacología , Antifúngicos/química , Candida/efectos de los fármacos , Cryptococcus/efectos de los fármacos , Ciclodextrinas/química , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
Aspergillus is a ubiquitous fungus which can cause a variety of clinical syndromes. This fungus has emerged as agent of systemic infections and has therefore gained considerable public health importance. This paper describes two cases of invasive aspergillosis caused by A. fumigatus in immuno-suppressed patients and underscores the importance of early identification of Aspergillus infection associated with systemic lupus erythematosus and cardiac postoperative complications.
RESUMEN
Mycosis is a major contributor to morbidity and mortality in patients with systemic lupus erythematosus and frequent exposition to an infectious source could enhance the development of dermatophytic infections. A case of disseminated dermatophytosis by Microsporum gypseum is reported in a systemic lupus erythematosus (SLE) patient.
RESUMEN
Candida esophagitis (CE) is a common opportunistic infection in the immunocompromised host. C. glabrata is rarely cited as agent of CE and has been underestimated due to lack of proper identification. In this study, two cases of C. glabrata esophagitis in AIDS and chagasic patients are reported. Diagnosis of Candida species should be considered an important key for the ideal choice of antifungal therapy against this mycosis.
RESUMEN
This communication reports the second known case of oral phaeohyphomycosis in a patient with squamocellular carcinoma of the lip. The patient, an 82-year-old black woman, a former smoker (for more than 30 years), suffering from an ulcerous vegetative lesion in the middle third of the lower lip for approximately 12 months. The result of the histopathological analysis indicated carcinoma, with well-differentiated keratinized squamous cells and the presence of septate mycelial filaments. In the direct mycological examination, thick and dematiaceous septate mycelial filaments were observed. After the resection surgery, the patient did not need to use an antifungal drug to treat the phaeohyphomycosis, and no follow-up radiotherapy was needed to treat the squamocellular carcinoma. We stress that the presence of the squamocellular lesion of the lip was a possible contributing factor to the infection.
Asunto(s)
Carcinoma de Células Escamosas/complicaciones , Neoplasias de los Labios/complicaciones , Labio/patología , Feohifomicosis/diagnóstico , Feohifomicosis/patología , Anciano de 80 o más Años , Brasil , Carcinoma de Células Escamosas/cirugía , Femenino , Histocitoquímica , Humanos , Labio/cirugía , Neoplasias de los Labios/cirugía , Técnicas Microbiológicas , Microscopía , Feohifomicosis/cirugía , Resultado del TratamientoRESUMEN
The majority of microorganisms present a community lifestyle, establishing biofilm ecosystems. However, little is known about its formation in emergent Candida species involved in catheter-related infections. Thus, various techniques may be used in the biofilm detection to elucidate structure and clinical impact. In this context, we report the ability of emergent Candida species (Candida haemulonii, C. lusitaniae, C. pelliculosa, C.guilliermondii, C. famata and C. ciferrii) on developing well structured biofilms with cell viability and architecture, using optical coherence tomography (OCT). This new approach was compared with XTT analyses and Scanning Electron Microscopy (SEM). A positive correlation between oxidative activity (XTT) and OCT results (r = 0.8752, p < 0.0001) was observed. SEM images demonstrated cells attachment, multilayer and morphologic characteristics of the biofilm structure. C. lusitaniae was the emergent species which revealed the highest scattering extension length and oxidative metabolism when evaluated by OCT and XTT methods, respectively. Herein, information on C. ciferri biofilm structure were presented for the first time. The OCT results are independently among Candida strains and no species-specific pattern was observed. Our findings strongly contribute for clinical management based on the knowledge of pathogenicity mechanisms involving emergent yeasts.
Asunto(s)
Biopelículas , Candida/fisiología , Tomografía de Coherencia Óptica/métodos , Candida/clasificación , Microscopía Electrónica de Rastreo , Especificidad de la EspecieRESUMEN
Infections caused by emerging Cryptococcus non-neoformans species are being reported with increasingly frequency. Here, we present a case of fungaemia by Cryptococcus laurentii in a woman receiving aggressive immunosuppressive therapy for cervical neoplasia. Three venous blood samples were aseptically collected on consecutive days and C. laurentii was isolated and identified through phenotypic and molecular methods. After central venous catheter removal and appropriate antifungal therapy, the patient showed significant improvement and blood culture became negative. Thus, patients following immunosuppressive therapies and using invasive medical devices are at risk of C. laurentii blood infections.
Asunto(s)
Criptococosis/microbiología , Fungemia/microbiología , Huésped Inmunocomprometido/inmunología , Displasia del Cuello del Útero/complicaciones , Neoplasias del Cuello Uterino/complicaciones , Adulto , Criptococosis/diagnóstico , Criptococosis/inmunología , Cryptococcus/genética , Cryptococcus/aislamiento & purificación , Femenino , Fungemia/diagnóstico , Fungemia/inmunología , Humanos , Neoplasias del Cuello Uterino/microbiología , Displasia del Cuello del Útero/microbiologíaRESUMEN
We report a case of invasive infection due to Saprochaete capitata in a patient with hematological malignancies after chemotherapy treatment and empiric antifungal therapy with caspofungin. Although severely immunocompromised the patient survived been treated with amphotericin B lipid complex associated with voriconazole.
Asunto(s)
Fungemia/diagnóstico , Fungemia/patología , Neoplasias Hematológicas/complicaciones , Saccharomycetales/aislamiento & purificación , Adolescente , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Caspofungina , Equinocandinas/uso terapéutico , Fungemia/microbiología , Humanos , Lipopéptidos , Pulmón/patología , Masculino , Pruebas de Sensibilidad Microbiana , Técnicas Microbiológicas , Microscopía , Radiografía Torácica , Resultado del Tratamiento , Voriconazol/uso terapéuticoRESUMEN
Abstract This communication reports the second known case of oral phaeohyphomycosis in a patient with squamocellular carcinoma of the lip. The patient, an 82-year-old black woman, a former smoker (for more than 30 years), suffering from an ulcerous vegetative lesion in the middle third of the lower lip for approximately 12 months. The result of the histopathological analysis indicated carcinoma, with well-differentiated keratinized squamous cells and the presence of septate mycelial filaments. In the direct mycological examination, thick and dematiaceous septate mycelial filaments were observed. After the resection surgery, the patient did not need to use an antifungal drug to treat the phaeohyphomycosis, and no follow-up radiotherapy was needed to treat the squamocellular carcinoma. We stress that the presence of the squamocellular lesion of the lip was a possible contributing factor to the infection.
Asunto(s)
Humanos , Femenino , Anciano de 80 o más Años , Neoplasias de los Labios/complicaciones , Carcinoma de Células Escamosas/complicaciones , Feohifomicosis/diagnóstico , Feohifomicosis/patología , Labio/patología , Brasil , Neoplasias de los Labios/cirugía , Carcinoma de Células Escamosas/cirugía , Técnicas Microbiológicas , Resultado del Tratamiento , Feohifomicosis/cirugía , Histocitoquímica , Labio/cirugía , MicroscopíaRESUMEN
INTRODUCTION: Onychomycosis is common in immunocompromised patients, but emerging species have been verified, thereby modifying the epidemiological profile of this mycosis. Thus, the aim of this study was to evaluate clinical and mycological profile of onychomycosis among HIV/AIDS patients. METHODS: Clinical samples were collected and processed for direct examination, and cultures were maintained at a temperature of 30 °C and 37 °C for 15 days. RESULTS: Out of 100 patients, 32 had onychomycosis. The etiological agents isolated were Candida albicans, C. parapsilosis, C. tropicalis, C. guilliermondii, Trichophyton rubrum, T. mentagrophytes, Fusarium solani, Scytalidium hialinum, S. japonicum, Aspergillus niger, Cylindrocarpon destructans and Phialophora reptans. CONCLUSIONS: Onychomycosis in HIV/AIDS patients presents various clinical manifestations and may be caused by emerging fungi. The peculiarities presented by different fungal agents justify the need for identification to species level, with the purpose of guiding better therapeutic approaches and minimizing these patients' exposure to conditions presenting a risk of disseminated infection.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Dermatosis del Pie/microbiología , Dermatosis de la Mano/microbiología , Onicomicosis/microbiología , Adulto , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
ABSTRACT Infections caused by emerging Cryptococcus non-neoformans species are being reported with increasingly frequency. Here, we present a case of fungaemia byCryptococcus laurentii in a woman receiving aggressive immunosuppressive therapy for cervical neoplasia. Three venous blood samples were aseptically collected on consecutive days and C. laurentiiwas isolated and identified through phenotypic and molecular methods. After central venous catheter removal and appropriate antifungal therapy, the patient showed significant improvement and blood culture became negative. Thus, patients following immunosuppressive therapies and using invasive medical devices are at risk of C. laurentii blood infections.
Asunto(s)
Adulto , Femenino , Humanos , Displasia del Cuello del Útero/complicaciones , Criptococosis/microbiología , Fungemia/microbiología , Huésped Inmunocomprometido/inmunología , Neoplasias del Cuello Uterino/complicaciones , Displasia del Cuello del Útero/microbiología , Criptococosis/diagnóstico , Criptococosis/inmunología , Cryptococcus/genética , Cryptococcus/aislamiento & purificación , Fungemia/diagnóstico , Fungemia/inmunología , Neoplasias del Cuello Uterino/microbiologíaRESUMEN
We report a case of invasive infection due to Saprochaete capitata in a patient with hematological malignancies after chemotherapy treatment and empiric antifungal therapy with caspofungin. Although severely immunocompromised the patient survived been treated with amphotericin B lipid complex associated with voriconazole.