RESUMEN
BACKGROUND: Dermatophytosis, caused by dermatophytes, affects up to 25% of people globally, with higher rates observed in Africa and Asia. While these infections are usually superficial, they can become severe in immunocompromised individuals. Despite their high prevalence, scientific research on dermatophytes is limited and the epidemiological data available are insufficient. In addition, diagnostic methods are not standardised and there are challenges with resistance to antifungals. OBJECTIVES: This study aimed to conduct a bibliometric analysis of scientific publications related to dermatophytes and dermatophytosis to assess research output and trends. METHODS: A bibliometric analysis of publications from 2000 to 2023 in Web of Science and Scopus examined trends, citation counts, publication types, key journals, top authors and institutions and funding sources. RESULTS: The analysis revealed a significant increase in dermatophyte-related publications, with 15,868 articles retrieved from the Web of Science and 23,189 from Scopus. Research articles dominated the output, constituting 76.2% in Web of Science and 80% in Scopus. Peak publication years were 2019, 2021 and 2022 in Web of Science, and 2020, 2021 and 2023 in Scopus, with lower output between 2000 and 2002. The United States and India were the leading contributors, followed by Brazil and China, though citation metrics varied. Although there has been a rise in the number of publications, the amount of research conducted on dermatophytes is still very limited in comparison with other types of fungal diseases. CONCLUSIONS: Dermatophyte-related research has increased over the past 2 decades. However, research gaps remain, particularly compared with other fungal diseases. Advances in diagnostics, antifungal testing and taxonomic classification are urgently needed. The study underscores the need for continued research and global collaboration to address these issues.
Asunto(s)
Arthrodermataceae , Bibliometría , Tiña , Arthrodermataceae/aislamiento & purificación , Arthrodermataceae/clasificación , Humanos , Tiña/epidemiología , Tiña/microbiología , Tiña/tratamiento farmacológico , Salud Global , Investigación Biomédica/tendencias , Antifúngicos/uso terapéuticoRESUMEN
Background: Dermatophytosis is a contagious fungal infection that affects mainly cats. It poses significant challenges in veterinary medicine due to its zoonotic potential and impact on animal and public health. Rapid and reliable diagnosis is crucial for preventing the spread of the disease, guiding treatment decisions, and monitoring disease control efforts. Although there are several studies on diagnostic methods in feline dermatophytosis, the comparison between them from the same sample lacks data. The absence of a universally accepted gold standard diagnostic method highlights the need for a multifaceted approach to diagnosing feline dermatophytosis. Aim: This study aims to assess the accuracy and efficacy of different diagnostic techniques comprehensively. Methods: For this, 48 samples of cats were analyzed by dermoscopy, direct hair examination, fungal culture using various media (Mycosel, Sabouraud, and Dermatophyte Test Medium), and polymerase chain reaction (PCR). Results: Direct examination and dermoscopy yielded unsatisfactory results. Mycosel and Sabouraud were suboptimal. DTM demonstrated superior selectivity, making it the most reliable among traditional methods. PCR was the top performer, exhibiting singular sensitivity, specificity, and accuracy. Conclusion: The study suggests that PCR may be the preferred choice for diagnosing feline dermatophytosis in clinical practice, especially when rapid and accurate results are essential.
Asunto(s)
Enfermedades de los Gatos , Reacción en Cadena de la Polimerasa , Sensibilidad y Especificidad , Tiña , Gatos , Animales , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/microbiología , Tiña/veterinaria , Tiña/diagnóstico , Tiña/microbiología , Reacción en Cadena de la Polimerasa/veterinaria , Dermoscopía/veterinaria , Dermatomicosis/veterinaria , Dermatomicosis/diagnóstico , Dermatomicosis/microbiologíaRESUMEN
Microsporum canis, one of the most widespread dermatophytes worldwide, is a zoonotic microorganism that transmits infection from reservoirs such as cats and dogs to humans. This microorganism is associated with Tinea corporis and other clinical manifestations; however, few studies have used genetic surveillance to determine and characterize the process of zoonotic transmission. In this study, we show a clear example of zoonotic transmission from a cat to an intrafamilial environment, where it caused Tinea corporis by infection with M. canis. Molecular characterization using the b-tubulin gene and Random Amplified Polymorphic DNA analysis made it possible to determine that the six isolates of M. canis obtained in this study belonged to the same genetic variant or clone responsible for reservoir-reservoir or reservoir-human transmission.
Asunto(s)
Enfermedades de los Gatos , Microsporum , Tiña , Zoonosis , Microsporum/aislamiento & purificación , Microsporum/genética , Microsporum/clasificación , Gatos/microbiología , Animales , Tiña/microbiología , Tiña/transmisión , Tiña/veterinaria , Enfermedades de los Gatos/microbiología , Enfermedades de los Gatos/transmisión , Zoonosis/microbiología , Zoonosis/transmisión , Mascotas/microbiología , Humanos , Perros , Técnica del ADN Polimorfo Amplificado Aleatorio , Masculino , Femenino , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/transmisión , ADN de Hongos/genéticaRESUMEN
Trichophyton rubrum is a human fungal pathogen that causes dermatophytosis, an infection that affects keratinized tissues. Integrated molecular signals coordinate mechanisms that control pathogenicity. Transcriptional regulation is a core regulation of relevant fungal processes. Previous RNA sequencing data revealed that the absence of the transcription factor StuA resulted in the differential expression of the MAPK-related high glycerol osmolarity gene (hog1) in T. rubrum. Here we validated the role of StuA in regulating the transcript levels of hog1. We showed through RT-qPCR that transcriptional regulation controls hog1 levels in response to glucose, keratin, and co-culture with human keratinocytes. In addition, we also detected hog1 pre-mRNA transcripts that underwent alternative splicing, presenting intron retention in a StuA-dependent mechanism. Our findings suggest that StuA and alternative splicing simultaneously, but not dependently, coordinate hog1 transcript levels in T. rubrum. As a means of preventing and treating dermatophytosis, our results contribute to the search for new potential drug therapies based on the molecular aspects of signaling pathways in T. rubrum.
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Empalme Alternativo , Arthrodermataceae , Regulación Fúngica de la Expresión Génica , Proteínas Quinasas Activadas por Mitógenos , Tiña , Factores de Transcripción , Humanos , Arthrodermataceae/genética , Arthrodermataceae/metabolismo , Glucosa/metabolismo , Queratinocitos/microbiología , Queratinas/metabolismo , Proteínas Quinasas Activadas por Mitógenos/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Tiña/metabolismo , Tiña/microbiologíaAsunto(s)
Tiña , Trichophyton , Tiña/microbiología , Tiña/patología , Tiña/tratamiento farmacológico , Humanos , Brasil , Animales , Trichophyton/aislamiento & purificación , Cobayas , Masculino , FemeninoRESUMEN
Dermatophytosis is a superficial cutaneous infection, most commonly caused by fungal species such as Microsporum canis, Nannizzia gypsea (Microsporum gypseum), and Trichophyton mentagrophytes in dogs and cats. The zoonotic potential of these species is concerning, as companion animals are increasingly close to their owners. Therefore, the objectives of the study were to evaluate the current prevalence of Nannizzia-causing canine and feline dermatophytosis in Curitiba and Metropolitan Region, as well as perform phenotypic and phylogenetic characterizations of these isolates. Thus, 241 skin and fur samples from 163 dogs and 78 cats were analyzed from 2020 to 2021. The samples were obtained from animals of three sources: Veterinary Hospital of the Federal University of Paraná, animal shelters, and private clinics. The diagnosis was performed through phenotypic characterization and sequencing ITS rDNA region. Among 97 positive samples for dermatophytes, Nannizzia was identified in 14 (14.4%) samples, while other dermatophyte genera were found in the remaining 83 (85.6%) samples. Among the canine samples, nine (90%) were N. gypsea, and one (10%) was N. incurvata. Whereas in feline samples, three (75%) were N. gypsea, and one (25%) was N. incurvata. It was concluded that among 97 animals infected with dermatophytes, dogs (24.4%; 10/41) were significantly more affected by Nannizzia than cats (7.1%; 4/56) (P < .05). According to molecular analyses, the ITS rDNA region provided satisfactory results for species-level identification of Nannizzia, confirming the first report of N. incurvata as an etiological agent of canine and feline dermatophytosis in Brazil.
Nannizzia genus affected significantly more dogs (24.4%) than cats (7.1%) (P < .05). The ITS rDNA exhibited higher accuracy for identifying dermatophytes compared to phenotypic diagnosis, allowing the confirmation of the first reports of N. incurvata as an etiological agent of dermatophytosis in dogs and cats in Brazil.
Asunto(s)
Arthrodermataceae , Enfermedades de los Gatos , Dermatomicosis , Enfermedades de los Perros , Tiña , Animales , Gatos , Perros , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Gatos/epidemiología , Enfermedades de los Gatos/microbiología , Brasil/epidemiología , Filogenia , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/microbiología , Microsporum , Tiña/microbiología , Tiña/veterinaria , ADN Ribosómico , Dermatomicosis/epidemiología , Dermatomicosis/veterinaria , Dermatomicosis/microbiologíaRESUMEN
BACKGROUND: Dermatophytosis is one of the most common fungal infections worldwide. The distribution of dermatophytes varies across continents, but the genera Trichophyton and Microsporum have emerged as the main isolated agents in humans and animals. OBJECTIVES: To validate Drosophila melanogaster flies as a fast and feasible model to study dermatophytic infections. METHODS: Wild-type (WT) and Toll-deficient D. melanogaster flies were infected by Trichophyton rubrum, T. mentagrophytes, Microsporum canis and Nannizzia gypsea by pricking with a needle previously dipped in inoculum concentrations ranging from 103 to 108 colony-forming units/mL. Establishment of infection was confirmed by survival curves, histopathological analysis and fungal burden. Thereafter, flies were treated with terbinafine, itraconazole and clioquinol. RESULTS: WT flies were predominantly resistant to the infection, whereas Toll-deficient flies succumbed to the four dermatophyte genera tested. The antifungal drugs protected flies from the infection, except for N. gypsea whose survival curves did not differ from the untreated group. CONCLUSIONS: This pilot study confirms that D. melanogaster is a suitable model to study the virulence and antifungal drug efficacy in dermatophyte species.
Asunto(s)
Arthrodermataceae , Tiña , Humanos , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Drosophila melanogaster , Proyectos Piloto , Itraconazol , Trichophyton , Tiña/tratamiento farmacológico , Tiña/microbiologíaRESUMEN
Dermatophytosis is the most common human skin infection worldwide caused by dermatophytes, such as Trichophyton interdigitale and Trichophyton rubrum. Itraconazole (ITZ) is one of the main antifungals used to treat these infections. However, especially for onychomycosis, the treatment requires long-term regimens, increasing the possibility of drug resistance. We evaluated the effects of ITZ in the physiology, virulence, and interaction of T. interdigitale with phagocytes and mice cutaneous infection. In a screening test, fungal growth in the presence of ITZ led to the spontaneous selection of less susceptible T. interdigitale and T. rubrum strains. Interestingly, this phenotype was permanent for some T. interdigitale strains. Then, we studied three T. interdigitale strains: one susceptible and two ITZ-adapted. The ITZ-adapted strains were also less susceptible to the cell wall and membrane stressors, suggesting a multidrug resistance (MDR) phenotype associated with the increased ERG11 and MDR3 expression. These strains also presented substantial alterations in ergosterol content, lipid peroxidation, biofilm, and extracellular matrix production. During interaction with macrophages, ITZ-adapted strains were less engulfed but increased the intracellular oxidative and nitrosative bursts. In addition, ITZ-adapted strains presented a reduced ability to grow in a murine model of dermatophytosis, although causing the same tissue damage as the parental strain. In conclusion, the T. interdigitale ITZ adaptation increases tolerance to antifungals and alters the interaction with macrophages and a mammalian host. We hypothesized that successive exposure to ITZ may influence the emergence of adapted strains and lead to the recalcitrance of dermatophytosis.
Asunto(s)
Arthrodermataceae , Enfermedades de los Roedores , Tiña , Humanos , Ratones , Animales , Itraconazol/farmacología , Itraconazol/uso terapéutico , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Trichophyton , Tiña/microbiología , Tiña/veterinaria , Virulencia , Pruebas de Sensibilidad Microbiana/veterinaria , MamíferosRESUMEN
Dermatophytoses are fungal infections affecting the skin and cutaneous annexes. This clinical case report describes a 7-year-old girl with Kerion celsi, a severe manifestation of Tinea capitis. The patient presented with painful edematous crusty scalp lesions and alopecia, which required surgical debridement and long-term antifungal treatment. Culture of samples collected from scalp and arm skin lesions (patient and patient's mother respectively) were positive for Trichophyton mentagrophytes. The family owned a pet guinea pig. This particular dermatophytosis is easily transmitted from guinea pigs to humans, with some studies showing up to 34.9% prevalence of Trichophyton mentagrophytes infection in these animals.
Asunto(s)
Tiña del Cuero Cabelludo , Tiña , Alopecia/diagnóstico por imagen , Alopecia/tratamiento farmacológico , Animales , Antifúngicos , Cobayas , Humanos , Piel/diagnóstico por imagen , Piel/patología , Tiña/tratamiento farmacológico , Tiña/microbiología , Tiña/patología , Tiña del Cuero Cabelludo/diagnóstico por imagen , Tiña del Cuero Cabelludo/tratamiento farmacológico , Tiña del Cuero Cabelludo/epidemiologíaRESUMEN
El Microsporum gypseum es un hongo geofílico que puede producir lesiones cutáneas inflamatorias en personas sanas. Se han descripto lesiones más extensas en pacientes inmunocomprometidos. Se presenta el caso de un paciente con dermatofitosis, con exámenes micológicos positivos para Candida sp, Epidermophytom floccosum y Trichophyton tonsurans, al que, ante la mala respuesta al tratamiento con griseofulvina e itraconazol a dosis habituales, se le realizó biopsia cutánea para cultivo que evidenció la presencia de M. gypseum. Debido a la extensión y a la mala respuesta al tratamiento, se realizó evaluación inmunológica y se diagnosticó un defecto en STAT1 con ganancia de función (STAT1-GOF). Los pacientes que tienen esta inmunodeficiencia primaria son susceptibles a las infecciones micóticas, especialmente por Candida, pero también, aunque en menor medida, a virus y bacterias. El paciente aquí presentado recibió tratamiento prolongado con antimicóticos imidazólicos sistémicos, con resolución de las lesiones.
Microsporum gypseum is a geophilic fungus that can cause inflammatory skin lesions in heathy people. More extensive lesions have been described in immunocompromised patients. We present a patient with extensive dermatophytosis, which mycological examination led the identification of Candida sp, Epidermophyton Floccosum and Trichophyton tonsurans and showed poor response to treatment with griseofulvina and itraconazol at usual doses. When skin biopsy was performed, it had positive culture for M. gypseum. Due to the extension and poor response to treatment, immunological assessment was performed and it showed a defect of STAT1 with gain of function (STAT 1-GOF). Patients with primary immunodeficiency are susceptible to fungal infections, especially Candida but also virus and bacteria, although to a lesser extent. The patient received long-term treatment with systemic imidazole antifungal recovering for the lesions.
Asunto(s)
Humanos , Masculino , Niño , Tiña/diagnóstico , Tiña/microbiología , Tiña/tratamiento farmacológico , Dermatomicosis/diagnóstico , Dermatomicosis/microbiología , Dermatomicosis/tratamiento farmacológico , Trichophyton , Arthrodermataceae , MicrosporumRESUMEN
Microsporum gypseum is a geophilic fungus that can cause inflammatory skin lesions in heathy people. More extensive lesions have been described in immunocompromised patients. We present a patient with extensive dermatophytosis, which mycological examination led the identification of Candida sp, Epidermophyton Floccosum and Trichophyton tonsurans and showed poor response to treatment with griseofulvina and itraconazol at usual doses. When skin biopsy was performed, it had positive culture for M. gypseum. Due to the extension and poor response to treatment, immunological assessment was performed and it showed a defect of STAT1 with gain of function (STAT 1-GOF). Patients with primary immunodeficiency are susceptible to fungal infections, especially Candida but also virus and bacteria, although to a lesser extent. The patient received long-term treatment with systemic imidazole antifungal recovering for the lesions.
El Microsporum gypseum es un hongo geofílico que puede producir lesiones cutáneas inflamatorias en personas sanas. Se han descripto lesiones más extensas en pacientes inmunocomprometidos. Se presenta el caso de un paciente con dermatofitosis, con exámenes micológicos positivos para Candida sp, Epidermophytom floccosum y Trichophyton tonsurans, al que, ante la mala respuesta al tratamiento con griseofulvina e itraconazol a dosis habituales, se le realizó biopsia cutánea para cultivo que evidenció la presencia de M. gypseum. Debido a la extensión y a la mala respuesta al tratamiento, se realizó evaluación inmunológica y se diagnosticó un defecto en STAT1 con ganancia de función (STAT1-GOF). Los pacientes que tienen esta inmunodeficiencia primaria son susceptibles a las infecciones micóticas, especialmente por Candida, pero también, aunque en menor medida, a virus y bacterias. El paciente aquí presentado recibió tratamiento prolongado con antimicóticos imidazólicos sistémicos, con resolución de las lesiones.
Asunto(s)
Dermatomicosis , Tiña , Arthrodermataceae , Niño , Dermatomicosis/diagnóstico , Dermatomicosis/tratamiento farmacológico , Dermatomicosis/microbiología , Humanos , Microsporum , Tiña/diagnóstico , Tiña/tratamiento farmacológico , Tiña/microbiología , TrichophytonRESUMEN
OBJECTIVES: Dermatomycoses, fungal diseases that affect the superficial layers of skin, hair or nails, are a public health concern due to their high prevalence. In Brazil, dermatomycoses are not notifiable diseases, so only fragmented epidemiological studies have been reported in the national literature. To evaluate the epidemiological profile of dermatomycoses in preschoolers and school children in Sinop, Mato Grosso (MT), Brazil. METHODS: Classic methods were used to perform 782 mycological examinations to identify dermatophytosis, cutaneous candidosis and pityriasis versicolor in preschoolers and school children aged between 6 months and 12 years in 11 educational institutions in Sinop, MT. RESULTS: Among the evaluated clinical specimens, 5.2% tested positive for dermatophytosis, with 58.45% of these cases corresponding to tinea capitis, followed by skin (tinea corporis and tinea pedis) and toenail (tinea unguium) lesions; zoophilic fungi predominated. Microsporum canis and Trichophyton mentagrophytes complex were isolated in 53.66% and 24.39% of the cases, respectively. Regarding cutaneous candidosis, 9.1% of the specimens tested positive for this disease, with 59.16% and 12.7% of the cases corresponding to toenails and interdigitoplantar lesions, respectively. Candida albicans caused 70.43% of the lesions. The remaining specimens (85.7%) tested positive for pityriasis versicolor; children aged between 6 and 12 were the most affected (71.79%). CONCLUSION: Our results agree with most epidemiological studies carried out in Brazil and demonstrate the high frequency of mycoses in preschoolers and school children, a result of poor personal hygiene and favourable weather conditions in Northern Mato Grosso, Brazil.
Asunto(s)
Candidiasis Cutánea , Dermatomicosis , Onicomicosis , Tiña Versicolor , Tiña , Brasil/epidemiología , Niño , Dermatomicosis/epidemiología , Dermatomicosis/microbiología , Humanos , Lactante , Onicomicosis/microbiología , Tiña/microbiologíaRESUMEN
Las dermatofitosis corresponden a un grupo de enfermedades micóticas comunes en piel y fanéreas, donde Trichophyton rubrum es el agente causante más frecuente a nivel mundial y presente en nuestros 2 casos de pacientes masculinos con estas micosis, una en uñas y la otra en piel. Sin embargo, el enfoque de esta publicación se basa principalmente en la presencia de 2 interesantes contaminantes (uno en cada caso clínico) presentes solo en los cultivos de las primeras siembras como saprófitos y por ende como propágulos de dispersión, asociados al ambiente y sin intervención clínica demostrada en ambas micosis. La descripción morfofisiológica de estos 2 contaminantes Metarhizium purpureo-genum(similis) y Monascus ruber fue más bien una curiosidad esencial que el micólogo clínico adquiere en su contínua formación y ante la posibilidad de infecciones mixtas, pudiendo conjugar sus hallazgos junto al análisis taxonómico y los factores geográficos y edáficos asociados a su distribución. (AU)
Dermatophytoses belongs to a group of common mycotic diseases in skin and pharynals, where Trichophyton rubrum is the most frequent causative agent worldwide and present in our 2 cases of male patients with these mycoses, one in nails and the other in skin. However, the focus of this publication is mainly about the presence of 2 interesting contaminants (one in each clinical case) present only in the crops of the first sowings as saprophytes and therefore as dispersal propagules, associated with the environment and without clinical intervention demonstrated in both mycoses. The morphophysiological description of these 2 contaminants, Metarhizium purpureogenum (similis) and Monascus ruber was rather an essential curiosity that the clinical mycologist acquires in his continuous training and in the face of the possibility of mixed infections, being able to combine his findings together with the taxonomic analysis and the geographic and edaphic factors associated with its distribution. (AU)
Asunto(s)
Humanos , Masculino , Adulto , Persona de Mediana Edad , Trichophyton/crecimiento & desarrollo , Monascus/crecimiento & desarrollo , Metarhizium/crecimiento & desarrollo , Tiña/microbiología , Trichophyton/aislamiento & purificación , Trichophyton/ultraestructura , Cladosporium/crecimiento & desarrollo , Monascus/aislamiento & purificación , Olea/microbiología , Metarhizium/aislamiento & purificaciónRESUMEN
INTRODUCTION: The resistance of fungal species to drugs usually used in clinics is of great interest in the medical field. OBJECTIVE: To evaluate susceptibility and in vitro response of species of Trichophyton spp. to antifungal drugs of interest in clinical medicine. METHODS: 12 samples of clinical isolates from humans were used, nine of T. mentagrophytes and three of T. tonsurans. Susceptibility tests were performed according to the agar diffusion (AD) and broth microdilution (BM) methods. RESULTS: In the AD method, the species T. tonsurans presented a percentage of sensitivity of 33% in relation to amphotericin B and 66% to itraconazole, with 100% resistance to ketoconazole and fluconazole. T. mentagrophytes also showed 100% resistance to ketoconazole in this technique, with 11% sensitivity to ketoconazole, 22% to itraconazole and 22% of samples classified as sensitive dose dependent. In the MC method, the species T. tonsurans presented a sensitivity percentage of 66%, 55% and 33% in relation to ketoconazole, fluconazole and itraconazole, respectively. The T. mentagrophytes species presented sensitivity percentages of 11%, 11%, 33% and 55% for amphotericin B, itraconazole, ketoconazole and fluconazole, respectively. CONCLUSION: There was resistance in vitro of the species of T. mentagrophytes and T. tonsurans against the antifungal fluconazole and relative resistance against ketoconazole in the AD method. In BM, however, important percentages of sensitivity were observed for the two species analyzed in relation to the antifungals fluconazole and ketoconazole when compared to itraconazole and amphotericin B.
INTRODUÇÃO: A resistência de espécies fúngicas às drogas usualmente empregadas no meio clínico é motivo de grande interesse na área médica. OBJETIVO: Avaliar susceptibilidade e resposta in vitro de espécies de Trichophyton spp. a drogas antifúngicas de interesse em clínica médica. MÉTODOS: Foram utilizadas 12 amostras de isolados clínicos de humanos, sendo nove de T. mentagrophytes e três de T. tonsurans. Foram realizados testes de susceptibilidade segundo os métodos de difusão em ágar (DA) e microdiluição em caldo (MC). RESULTADOS: No método de DA, a espécie T. tonsurans apresentou percentual de sensibilidade de 33% em relação à anfotericina B e de 66% ao itraconazol, com 100% de resistência frente ao cetoconazol e ao fluconazol. A espécie T. mentagrophytes também apresentou 100% de resistência frente ao cetoconazol nesta técnica, com 11% de sensibilidade ao cetoconazol, 22% ao itraconazol e 22% das amostras classificadas como sensível dose dependente. No método de MC, a espécie T. tonsurans apresentou percentual de sensibilidade de 66%, 55% e 33% em relação ao cetoconazol, fluconazol e itraconazol, respectivamente. A espécie T. mentagrophytes apresentou percentuais de sensibilidade de 11%, 11%, 33% e 55% para anfotericina B, itraconazol, cetoconazol e fluconazol, respectivamente. CONCLUSÃO: Houve resistência in vitro das espécies do T. mentagrophytes e T. tonsurans frente ao antifúngico fluconazol e resistência relativa frente ao cetoconazol no método de DA. Na MC, no entanto, foram observados importantes percentuais de sensibilidade das duas espécies analisadas frente aos antifúngicos fluconazol e cetoconazol quando comparadas ao itraconazol e à anfotericina B.
Asunto(s)
Trichophyton/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Fúngica , Susceptibilidad a Enfermedades/microbiología , Antifúngicos/farmacología , Tiña/microbiología , Tiña/tratamiento farmacológico , Recuento de Colonia Microbiana , Fluconazol/farmacología , Anfotericina B/farmacología , Itraconazol/farmacología , Cetoconazol/farmacologíaRESUMEN
Dermatophytoses (ringworms) are among the most frequent skin infections and are a highly prevalent cause of human disease worldwide. Despite the incidence of these superficial mycoses in healthy people and the compelling evidence on chronic and deep infections in immunocompromised individuals, the mechanisms controlling dermatophyte invasion in the skin are scarcely known. In the last years, the association between certain primary immunodeficiencies and the susceptibility to severe dermatophytosis as well as the evidence provided by novel experimental models mimicking human disease have significantly contributed to deciphering the basic immunological mechanisms against dermatophytes. In this review, we outline the current knowledge on fungal virulence factors involved in the pathogenesis of dermatophytoses and recent evidence from human infections and experimental models that shed light on the cells and molecules involved in the antifungal cutaneous immune response. The latest highlights emphasize the contribution of C-type lectin receptors signaling and the cellular immune response mediated by IL-17 and IFN-γ in the anti-dermatophytic defense and skin inflammation control.
Asunto(s)
Inmunidad Adaptativa , Arthrodermataceae/patogenicidad , Inmunidad Innata , Piel/microbiología , Tiña/microbiología , Animales , Arthrodermataceae/inmunología , Interacciones Huésped-Patógeno , Humanos , Inmunidad Celular , Transducción de Señal , Piel/inmunología , Tiña/inmunología , VirulenciaRESUMEN
BACKGROUND: Dermatophytosis is one of the most frequent superficial mycoses in the world. MAIN AIM: To describe the cases of skin dermatophytosis and its main aetiologic agents in patients referred to a Mycological Reference Laboratory in Medellín, Colombia. METHODS: A retrospective study was carried out with records of patients referred between 1994 and 2016 to the Corporación para Investigaciones Biológicas (CIB), Medellín-Colombia, because of clinical suspicion of skin dermatophytosis. RESULTS: Of a total of 5628 clinical records of patients with suspicion of skin dermatophytosis analysed, 2780 (49.4%) had a proven or probable dermatophytosis diagnosis, 2774 cultures were performed, and aetiologic agents were isolated in 2576 samples (92.9%). The most frequently isolated aetiologic agents were Trichophyton rubrum (44.3%), followed by Trichophyton mentagrophytes complex (33.3%), Epidermophyton floccosum (12.4%), Nannizzia gypseum complex (5.7%, formerly Microsporum gypseum), Microsporum canis (3.5%) and Trichophyton tonsurans (0.8%). The most frequent clinical forms were tinea pedis (72.7%) and tinea corporis (12.7%). In addition, a group of patients (0.9%) developed mixed infections by two dermatophyte agents and another (4.1%) developed infections in more than one anatomical site. CONCLUSIONS: The results of the present study are coherent with previous reports where T rubrum and T mentagrophytes complex were the main causative agents of dermatophytosis. However, the increased incidence of N gypsea complex over M canis is worth highlighting.
Asunto(s)
Dermatomicosis/epidemiología , Hongos/aislamiento & purificación , Tiña/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Arthrodermataceae/clasificación , Arthrodermataceae/aislamiento & purificación , Niño , Preescolar , Colombia/epidemiología , Dermatomicosis/microbiología , Epidermophyton/clasificación , Epidermophyton/aislamiento & purificación , Hongos/clasificación , Humanos , Lactante , Masculino , Microsporum/clasificación , Microsporum/aislamiento & purificación , Persona de Mediana Edad , Estudios Retrospectivos , Piel/microbiología , Piel/patología , Tiña/epidemiología , Trichophyton/clasificación , Trichophyton/aislamiento & purificación , Adulto JovenRESUMEN
The filamentous fungus Trichophyton rubrum is a pathogen that causes superficial mycoses in humans, predominantly in keratinized tissues. The occurrence of dermatophytoses has increased in the last decades, mainly in immunocompromised patients, warranting research on the mechanisms involved in dermatophyte virulence. The genomes of dermatophytes are known to be enriched in genes coding for proteins containing the LysM domain, a carbohydrate-binding module, indicating the possible involvement of these genes in virulence. Although the LysM domains have already been described in other fungi, their biological functions in dermatophytes are unknown. Here we assessed the transcription of genes encoding proteins containing the LysM domains in T. rubrum grown on different substrates using quantitative real-time polymerase chain reaction. Some of these genes showed changes in transcription levels when T. rubrum was grown on keratin. In silico analyses suggest that some of these proteins share features, namely, they are anchored in the plasma membrane and contain the catalytic domain chitinase II and signal peptide domains. Here we show a detailed study of genes encoding the proteins with LysM-containing domains in T. rubrum, aiming to contribute to the understanding of their functions in dermatophytes.
Asunto(s)
Proteínas Fúngicas/genética , Perfilación de la Expresión Génica , Trichophyton/crecimiento & desarrollo , Trichophyton/genética , Metabolismo de los Hidratos de Carbono , Quitinasas/genética , Biología Computacional , Medios de Cultivo , Regulación Fúngica de la Expresión Génica , Humanos , Queratinas , Señales de Clasificación de Proteína/genética , Tiña/microbiologíaRESUMEN
Each year, millions of people worldwide are affected by superficial mycoses, which are frequently caused by dermatophytes having affinity to the scalp, nails, hair and the stratum corneum of the skin. The changing reservoirs of zoophilic dermatophytes, the numerous reports of animal carrier status, and the increasing number of pets make the diagnosis difficult, which is usually impossible based only on medical history. Herein we present a case report of tinea corporis caused by Trichophyton equinum in siblings who had no contact with horses. The routine laboratory diagnostic procedures for identification of isolates were based on phenotypic and genotypic characteristics, especially molecular techniques using rDNA internal transcribed spacer sequences. The results showed that both techniques proved to be insufficiently discriminatory to differentiate two closely related species, i.e. Trichophyton equinum and Trichophyton tonsurans. Introduction of a TEF1 sequence analysis to the diagnostic procedures revealed consistent differences between these two species and facilitated unambiguous identification. Interestingly, dogs that could leave the homestead freely were the source of the infection in children. In conclusion, Trichophyton equinum was considered in the past as a strict zoophilic dermatophyte associated with horses and rarely transmitted to humans. This study revealed that this species can have other reservoirs and live in the fur of asymptomatic animals.
Asunto(s)
Arthrodermataceae/fisiología , Enfermedades de los Perros/microbiología , Tiña/veterinaria , Animales , Arthrodermataceae/genética , Arthrodermataceae/aislamiento & purificación , Enfermedades Asintomáticas , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/transmisión , Perros , Femenino , Genotipo , Masculino , Tiña/diagnóstico , Tiña/microbiología , Tiña/transmisiónRESUMEN
BACKGROUND: Ringworm are skin and its annexes infections. Trichophyton tonsurans is an emergent anthropophilic fungus that might cause outbreaks. AIM: To describe a ringworm outbreak by T tonsurans in an elementary school in Valparaíso, Chile. METHODS: A descriptive study was run between June and August, 2018. Students and his closest relatives in contact with them who were clinically diagnosed with ringworm have been considered a case. Mycological studies of samples had been carried out through morphophysiology tests. Data are shown in numbers and percentages. RESULTS: There were 18 cases, 16 kids (15 from kindergarten) and 2 adults. Attack rate was 68% in kindergarten. Nine cases were boys with average age of 6 years old. For 14 cases their nationality was Chilean and in 1 case Haitian. First case was a Chilean boy, and primary case was a Haitian boy. The most frequent location was face. Ten cases yielded positive cultures for T tonsurans. Most of the patients needed terbinafine treatment after a therapeutic failure performed with clotrimazole. CONCLUSION: T. tonsurans outbreak ocurred mainly in kindergarten male. The most frequent location was face. Most of the patients needed terbinafine treatment after a therapeutic failure with clotrimazole.
Asunto(s)
Brotes de Enfermedades , Tiña/epidemiología , Trichophyton/aislamiento & purificación , Niño , Preescolar , Chile/epidemiología , Femenino , Humanos , Masculino , Tiña/microbiologíaRESUMEN
Heat shock proteins (HSPs) are involved in critical processes like host tissue invasion, resistance, and pathogenicity in dermatophytes. RNA-Seq analysis of Trichophyton rubrum exposed to undecanoic acid (UDA) revealed intron retention events in HSP transcripts. Because HSPs are modulated in response to various stimuli and as alternative splicing (AS) can result in a broad diversity in the proteome of eukaryotic cells, our objective was to confirm the aforementioned retention events, investigating their consequences and extent. Furthermore, we aimed to determine: (1) the expression profile of HSP genes in an infection-like scenario and (2) the importance of Hsp90 for the keratinolytic potential of T. rubrum. RT and qPCR analyses comparing the exposure to UDA and terbinafine (TRB) confirmed the presence of two mRNA isoforms of the hsp7-like gene, with distinct expression patterns in response to UDA and TRB. The HSP expression profile revealed two upregulated, three downregulated, and four unmodulated transcripts; Hsp90 inhibition by 17-AAG resulted in a significant decrease in keratinolytic potential at 37 °C. Altogether, these results broaden the current knowledge on the importance of HSP-mediated pathways for cell adaptation and other aspects of dermatophyte biology, indicating that HSP network proteins can be potential targets for antifungal therapy.