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.
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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.
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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.
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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/microbiologíaRESUMEN
Los dermatofitos son un grupo de hongos responsables de las dermatofitosis o tiñas, pudiendo afectar piel, uñas y pelo. En la actualidad están constituidos por los géneros Epidermophyton, Trichophyton, Microsporum, Arthroderma, Paraphyton, Lophophyton y Nannizzia. El examen microscópico directo y el cultivo en agar siguen siendo el estándar de oro para la identificación, sin embargo, en ocasiones se requiere de la biología molecular para poder corroborar una determinada especie. Dependiendo de la localización, del número de lesiones y de la extensión, el tratamiento de las dermatofitosis puede ser tópico o sistémico. Trichophyton indotineae y T tonsurans pueden expresar resistencia a la terbinafina y azoles, respectivamente.
Dermatophytes are a group of fungi responsible for dermatophytosis or ringworm, which can affect the skin, nails and hair. Currently, they are assembled by the genera Epidermophyton, Trichophyton, Microsporum, Arthroderma, Paraphyton, Lophophyton and Nannizzia. Direct microscopic examination and culture on agar remain the gold standard for identification, however, molecular biology is sometimes required to confirm a certain species. Depending on the location, the number of lesions and the extension, the treatment of dermatophytosis can be topical or systemic. Trichophyton indotineae and T tonsurans can express resistance to terbinafine and azoles, respectively.
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Humanos , Tiña/diagnóstico , Tiña/tratamiento farmacológico , Arthrodermataceae/clasificaciónAsunto(s)
Tiña , Trichophyton , Tiña/microbiología , Tiña/patología , Tiña/tratamiento farmacológico , Humanos , Brasil , Animales , Trichophyton/aislamiento & purificación , Cobayas , Masculino , FemeninoRESUMEN
Trichophyton species cause dermatophytosis in humans, with a high, worldwide frequency of reports and important public health relevance. We evaluated 61 Trichophyton strains from different sources deposited in the University Recife Mycology (URM) culture collection of the Universidade Federal de Pernambuco, Brazil. Strains were phenotypically identified and confirmed by sequencing Internal Transcribed Spacers rDNA and partial beta-tubulin 2-exon. Additionally, we evaluated their susceptibility to terbinafine and itraconazole. Physiological analyses included urease activity and growth in casein medium. Phenotypic methods allowed the reliable identification of T. rubrum only, whereas, for other species, molecular methods were mandatory. All Trichophyton species exhibited susceptibility profiles to itraconazole (0.04-5.33 µg/mL) and terbinafine (0.17-3.33 µg/mL). Our analyses revealed a heterogeneous distribution of T. mentagrophytes, which does not support the current distribution within the species complex of T. mentagrophytes and its genotypes.
Asunto(s)
Arthrodermataceae , Tiña , Humanos , Trichophyton , Terbinafina/farmacología , Antifúngicos/farmacología , Itraconazol , Brasil , Universidades , Pruebas de Sensibilidad Microbiana , Arthrodermataceae/genéticaRESUMEN
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.
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Arthrodermataceae , Tiña , Humanos , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Drosophila melanogaster , Proyectos Piloto , Itraconazol , Trichophyton , Tiña/tratamiento farmacológico , Tiña/microbiologíaRESUMEN
Trichophyton, Microsporum, Nannizzia and Epidermophyton genera cause dermatophytosis, the most common and highly contagious infectious skin disease. Rio de Janeiro is one of the most visited cities in the Southern Hemisphere, located in the most visited state of Brazil. This retrospective study investigated epidemiological and laboratorial aspects of dermatophytosis in Rio de Janeiro state, Brazil, by using spatiotemporal analysis. More than half of all individuals were infected by one or more dermatophytes. A variation between 18 and 106 years-old of the studied population was verified, and women more frequently affected. Patients were more frequently infected by Trichophyton spp., most of them T. rubrum, followed by T. mentagrophytes. M. canis and N. gypsea were more frequently isolated in the age group between 40 and 60 years old, while T. rubrum predominates among younger patients. All species presented homogeneous distribution while T. tonsurans appears to be restricted to the Rio de Janeiro capital and E. floccosum to the municipality of Macaé (190 Km apart from RJ). Rio de Janeiro state presented spatial clusters of dermatophytosis with high density in Guanabara Bay (E. floccosum, M. canis, N. gypsea, T. tonsurans) and Niterói (T. rubrum, T. mentagrophytes) but low density in Macaé (E. floccosum). Significant spatiotemporal clusters on dermatophytosis cases were detected in distinct municipalities (p-value ≤ 0.05). The Vulnerability Index (r = 0.293) and Demographic Density (r = 0.652) distributed according to neighborhoods in Niterói were direct related with dermatophytosis cases whereas Income (r = -0.306) was inversely correlated (p-value ≤ 0.05). The dermatophytosis spatiotemporal distinct distribution after two major international events in Rio de Janeiro, Brazil, highlight the pressing need for specific measures of its prevention and controlling. This is particularly relevant in touristic tropical localities which must consider both socio-economical and traveler's medicine variables.
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Arthrodermataceae , Canidae , Dermatomicosis , Tiña , Animales , Humanos , Femenino , Adulto , Persona de Mediana Edad , Adolescente , Adulto Joven , Anciano , Anciano de 80 o más Años , Estudios Retrospectivos , Tiña/epidemiología , Brasil/epidemiología , Trichophyton , MicrosporumRESUMEN
The classical dermatophytes diagnosis is based on mycological culture and microscopy observation both human and animal hair, skin, and nail samples. The aim of this work was to develop the new in-house real-time PCR with pan-dematophyte reaction for detection and identification of the main dermatophytes directly from hair samples, providing a simple and rapid diagnosis of dermatophytosis in dogs and cats. An in-house SYBR-Green real-time PCR was designed and used for detecting a DNA fragment encoding chitin synthase 1 (CHS1). A total of 287 samples were processed by culture, microscopic examination with KOH 10%, and real-time PCR (qPCR) analysis. Melting curve analysis of the CHS1 fragment revealed to be reproducible, showing a single distinct peak for each species of dermatophyte, namely Trichophyton mentagrophytes, T. verrucosum, Microsporum canis, and Nannizzia gypsea (formerly M. gypseum). Then, out of the 287 clinically suspected cases of dermatophytosis, 50% were positive for dermatophytes by qPCR, 44% by mycological culture, and 25% by microscopic examination. Microsporum canis was identified in 117 samples tested by culture and 134 samples tested by qPCR, followed by N. gypsea in 5 samples (either tested by culture or qPCR) and T. mentagrophytes detected in 4 and 5 samples when tested by culture or qPCR, respectively. Overall, qPCR allowed the diagnosis of dermatophytosis in clinical samples. The results suggest this newly proposed in-house real-time PCR assay can be used as alternative diagnosis and rapid identification of dermatophytes frequently associated to clinical hair samples of dogs and cats.
The aim of this work was to develop a molecular detection strategy for dermatophytes by SYBR-Green real-time PCR of hair samples from animals. The melting curve analysis of the CHS1 fragment revealed to be reproducible, showing a single distinct peak for distinct dermatophyte species and allowed the diagnosis of dermatophytosis in dogs and cats caused mainly by Trichophyton mentagrophytes, Microsporum sp., and Nannizzia gypsea).
Asunto(s)
Arthrodermataceae , Enfermedades de los Gatos , Dermatomicosis , Enfermedades de los Perros , Tiña , Gatos , Animales , Perros , Humanos , Arthrodermataceae/genética , Dermatomicosis/diagnóstico , Dermatomicosis/veterinaria , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Enfermedades de los Gatos/diagnóstico , Enfermedades de los Perros/diagnóstico , Microsporum/genética , Cabello , Quitina Sintasa/genética , Tiña/veterinaria , Trichophyton/genéticaRESUMEN
Resumen Querión Celso es una micosis ocasionada por hongos dermatofitos que daña el cuero cabelludo principalmente a niños y en raras ocasiones a adultos. La forma de infección para los humanos proviene de los animales y del suelo y se relaciona con mala higiene personal, hacinamiento en las viviendas, condiciones de subdesarrollo y pobreza. Se presenta un caso de un niño de 9 años con una úlcera de 7 cm de diámetro en el cuero cabelludo y en forma de placa circular que presentaba material purulento, pelo quebradizo y un área alopécica. Al inicio, se abordó de manera terapéutica como una infección bacteriana; posteriormente, se solicitó estudio micológico que evidenció una coinfección por el microorganismo Microsporum gypseum. Se le confirmó el diagnóstico de tiña capitis con afección inflamatoria y se le prescribió griseofulvina, lo que resultó en una curación completa.
Abstract Kerion Celsi is a mycosis caused by dermatophyte fungi that mostly affects children and rarely adults, causing damage to the scalp. The form of infection for humans comes from animals and the soil. The infection is related to poor personal hygiene, overcrowded homes, underdeveloped conditions, and poverty. A case of a 9-year-old boy with a 7cm diameter ulcer on the scalp and in the form of a circular plaque that presented purulent material, brittle hair and an alopecic area is presented. Initially it was therapeutically addressed as a bacterial infection, a mycological study was requested, which showed coinfection by the microorganism Microsporum gypseum, the diagnosis of tinea capitis with inflammatory condition was confirmed, and Griseofulvin was prescribed, resulting in complete cure.
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Humanos , Masculino , Niño , Tiña , Tiña del Cuero Cabelludo/diagnóstico , Infecciones Bacterianas y Micosis , Microsporum , Costa RicaRESUMEN
Dermatophytosis is one of the most frequent superficial mycoses in the world. They are mainly caused by the dermatophytes Trichophyton rubrum and Microsporum canis. Biofilm production is an essential factor in the pathogenesis of dermatophytes; it confers drug resistance and significantly impairs antifungal effectiveness. Therefore, we evaluated the antibiofilm activity of an alkamide-type alkaloid called riparin 1 (RIP1) against clinically relevant dermatophytes. We also produced synthetic nor (NOR1) and dinor (DINOR1) homologs for pharmacological evaluation, with a 61-70% yield. We used in vitro (96-well polystyrene plates) and ex vivo (hair fragments) models to verify the effects of these compounds on the formation and viability of biofilms. RIP1 and NOR1 showed antifungal activity against strains of T. rubrum and M. canis, but DINOR1 showed no significant antifungal activity against the dermatophytes. Furthermore, RIP1 and NOR1 significantly reduced the viability of biofilms in vitro and ex vivo (P < 0.05). RIP1 was more potent than NOR1, possibly due to the distance between the p-methoxyphenyl and the phenylamide moieties in these compounds. Due to the significant antifungal and antibiofilm activities observed for RIP1 and NOR1, we suggest that they could be useful in the treatment of dermatophytosis.
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Arthrodermataceae , Dermatomicosis , Tiña , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Dermatomicosis/tratamiento farmacológico , BiopelículasRESUMEN
Introducción. Las dermatofitosis son infecciones fúngicas superficiales de epitelios queratinizados. La tinea capitis es una de ellas y afecta a poblaciones escolares vulnerables. Carpinelo es un barrio del área periférica de Medellín con precarias condiciones socioeconómicas. Ante la sospecha de un brote de dermatofitosis, los afectados fueron evaluados. Objetivo. Evaluar clínica y microbiológicamente pacientes del barrio Carpinelo con sospecha de micosis cutáneas para determinar la presencia de un brote por dermatofitos. Materiales y métodos. Se llevó a cabo un estudio descriptivo, de corte longitudinal, con muestreo a conveniencia. Se hizo una búsqueda activa de casos en el Jardín Educativo Buen Comienzo de Carpinelo en niños de la institución y sus familiares. Se evaluaron clínicamente y se tomaron muestras de escamas y cabellos para exámenes directos y cultivos microbiológicos. Se analizó el perfil demográfico, clínico y micológico, con el programa estadístico SPSS™, versión 25. Resultados. Se estudiaron 57 pacientes, 47 eran menores de edad con una media de edad de seis años; se observó una proporción de hombres y mujeres de 2:1. Los pacientes con resultados positivos se diagnosticaron con tinea capitis (78,95 %), tinea faciei (15,79 %) y tinea corporis (10,52 %). El 75,43 % de los pacientes recibió tratamiento previo y de estos el 69,73 % fue con esteroides. El examen directo fue positivo en el 53,84 % y los cultivos en el 46,5 % de los casos. Los agentes aislados fueron: Microsporum canis (77,77 %), Trichophyton spp. (11,11 %), Trichophyton rubrum (5,55 %) y Malassezia spp. (5,55 %). Conclusión. Tinea capitis fue la presentación clínica más común y M. canis el dermatofito más frecuentemente aislado. Llamó la atención el uso de esteroides como primera y única opción del tratamiento empírico' lo cual resalta la importancia del diagnóstico microbiológico para proporcionar la terapia apropiada.
Introduction. Dermatophytoses are superficial fungal infections of the keratinized epithelium like tinea capitis. The latte mainly affects school-vulnerable populations. Carpinelo is a peripheral neighborhood in Medellín with poor socioeconomic conditions and where a suspected tinea capitis outbreak took place. Objective. To study and characterize, clinically and microbiologically, patients with suspected dermatophytosis in Carpinelo. Materials and methods. We carried out a descriptive and longitudinal study with an active case search of tinea capitis in children and their relatives from the Jardín Educativo Buen Comienzo community in Carpinelo. Patients were clinically evaluated, and samples of scales and hair were taken to perform mycological studies with a 10 % potassium hydroxide and culture in Sabouraud and Mycosel agar. We analyzed the data with the statistical program SPSS™. 25 version. Results. Fifty-seven individuals were studied: 47 were children with a mean age of six years and a ratio of 2:1 male to female. Patients with confirmed diagnosis presented the following clinical forms: tinea capitis (78.95%), tinea faciei (15.79%) or tinea corporis (10.52%). Out of the total, 69.76% of the patients had previous treatment with steroids. The direct test was positive in 53.84% of the samples, and 46.15% had positive cultures. The isolated species were: Microsporum canis (77.77%), Trichophyton spp. (11.11%), Trichophyton rubrum (5.55%), and Malassezia spp. (5.55 %). Conclusion.Tinea capitis was the most common clinical form, and M. canis was the most frequently isolated species. The use of steroids as the first and only option for empiric treatment was worth of notice. The findings of this study point out the importance of microbiological diagnosis in choosing the best treatment for the patients.
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Tiña , Dermatomicosis , Tiña del Cuero Cabelludo , Brotes de EnfermedadesRESUMEN
In this retrospective study, the clinical and anatomopathological findings of fungal diseases in dogs and cats in Northeastern Brazil are described. During the study period, 6,827 histopathological examinations (4,090 necropsies and 2,737 biopsies) of companion animals were reviewed, and fungal infections were diagnosed in 54 cases. Of these, 32 cases were diagnosed in cats and 22 in dogs. Sporotrichosis was the most prevalent mycosis (19/54), followed by dermatophytosis (9/54), cryptococcosis (8/54), candidiasis (7/54), and phaeohyphomycosis (4/54). Other diseases had two cases each, including aspergillosis, mucormycosis, and histoplasmosis, whereas coccidioidomycosis occurred once. Mycoses were diagnosed through microscopic lesions associated with the histomorphological characteristics of the agent, as evidenced by routine and special histochemical stains. They were occasionally confirmed by immunohistochemistry and microbiological cultivation. This retrospective study showed that despite being uncommon, fungal diseases are important causes of death in dogs and cats in the region, with cats being the most affected species and sporotrichosis being the most prevalent mycosis. Clinical signs were correlated with the portal of entry of the infection associated with localized or disseminated superficial and deep skin lesions or affecting parenchymal organs, especially in systemic infections. Microscopic lesions were mainly characterized by pyogranulomatous inflammation associated with fungal structures. In dogs, mycoses occurred mainly owing to an immunological impairment secondary to canine distemper virus co-infection.
Neste estudo retrospectivo, são descritos os achados clínicos e anatomopatológicos das doenças fúngicas em cães e gatos no Nordeste do Brasil. Durante o período de estudo, foram revisados 6.827 exames histopatológicos (4.090 necropsias e 2.737 biópsias) de animais de companhia e diagnosticados 54 casos de infecções fúngicas. Destes, 32 casos foram diagnosticados em gatos e 22 em cães. A esporotricose foi a micose mais prevalente (19/54), seguida pela dermatofitose (9/54), criptococose (8/54), candidíase (7/54) e feo-hifomicose (4/54). Outras doenças tiveram dois casos cada, incluindo aspergilose, mucormicose e histoplasmose, enquanto a coccidioidomicose ocorreu uma vez. As micoses foram diagnosticadas por meio das lesões microscópicas associadas às características histomorfológicas do agente, evidenciadas pelas colorações de rotina e histoquímicas especiais, e ocasionalmente confirmadas pela imuno-histoquímica e cultivo microbiológico. Esse estudo retrospectivo demonstrou que apesar de incomuns, as doenças fúngicas são importantes causas de morte em cães e gatos da região, sendo os gatos a espécie mais afetada e a esporotricose, a micose mais prevalente. Os sinais clínicos estavam correlacionados com a porta de entrada da infecção, associados a lesões cutâneas localizadas ou disseminadas superficiais e profundas ou afetando órgãos parenquimatosos, especialmente em infecções sistêmicas. As lesões microscópicas eram caracterizadas principalmente por inflamação piogranulomatosa associada a estruturas fúngicas. Nos cães, as micoses ocorreram principalmente devido ao comprometimento imunológico secundária a coinfecção pelo vírus da cinomose canina.
Asunto(s)
Animales , Gatos , Perros , Enfermedades de los Gatos/microbiología , Enfermedades de los Perros/microbiología , Micosis/patología , Micosis/veterinaria , Micosis/epidemiología , Aspergilosis/veterinaria , Esporotricosis/veterinaria , Tiña/veterinaria , Brasil/epidemiología , Candidiasis/veterinaria , Gatos/microbiología , Coccidioidomicosis/veterinaria , Criptococosis/veterinaria , Perros/microbiología , Feohifomicosis/veterinaria , Histoplasmosis/veterinaria , Mucormicosis/veterinariaRESUMEN
Background: Dermatophytes, fungi of universal distribution, invade semi or fully keratinized structures, such as skin, fur/ hair and nails. The various species of dermatophytes are classified into three genera anamorphic: Microsporum, Trichophyton and Epidermophyton. The genus Epidermophyton includes only E. floccosum, that rarely affects animals. The main species responsible for the disease in dogs and cats are Microsporum canis, M. gypseum and Trichophyton mentagrophytes, which were characterized through conventional mycological methodology (microscopic examination with KOH and culture). Molecular methodologies, such as real-time PCR, can contribute to a rapid laboratory diagnosis, helping clinicians to initiate an early antifungal treatment. This case report describes a case of canine dermatophytosis due to Trichophyton mentagrophytes detected from a clinical sample by SYBR-Green real-time PCR. Case: A 8-year-old dog, rescued from the street, was referred to a private veterinary clinic in the city of Canoas, RS, Brazil, presenting generalized lymphadenomegaly, crusted lesions all over the body, generalized alopecia, signs of excoriation and epistaxis. Initially, were administered prednisone [1 mg/kg every 48 h, BID] and cephalexin [30 mg/kg, BID]. Weekly baths with benzoyl peroxide were also given. The therapy was not clinically successful. Wood's Lamp Test was negative. As a differential diagnosis, PCR for detection of Leishmania was negative. Complete blood count and serum biochemical assay were also performed. For mycological diagnosis, hair specimen was clarified and examined microscopically using 10% potassium hydroxide (KOH) for the visualization of chains of arthroconidia (ectothrix invasion of hair). The infected hair was plated onto MycoselTM Agar, incubated at 28°C for 15 days. Microscopy of hyphae/ conidia and macroscopic colony characteristics (colors and texture) were conducted for the differentiation of the species within the genus Microsporum and Trichophyton. In addition, real-time PCR was applied for direct analysis of the fungal DNA obtained from the hair sample. Microscopic examination was negative. The dermatophyte present in the hair sample was confirmed as Trichophyton mentagrophytes by culture and qPCR (melting-point analysis). The patient was treated with systemic itraconazole [10 mg/ kg SID - 90 days]. Twice-weekly application of 2.5 % miconazole and 2% chlorhexidine shampoo until complete cure. Discussion: Dermatophytosis is often listed as self-limiting infection; however, animal dermatophytosis can spread between pets, as well as a zoonotic transmission to humans. The literature on dermatophytosis indicates that Microsporum canis is the predominant etiological agent, followed by M. gypseum. Trichophyon mentagrophytes that appear in a lower percentage of isolation. The culture of hair, even with specific medium containing chloramphenicol and cyclohexamide, may present contaminating fungi, not related to dermatophytosis, which can inhibit or override the growth of dermatophytes. The use of real-time PCR provided a faster and specific diagnosis of dermatophytosis when compared to the conventional mycological methodology for detection and identification of T. mentagrophytes, which takes around 10 to 15 days for culture. It is possible to use this technique as an alternative diagnosis for dermatophytes associated to clinical hair samples of dogs.
Asunto(s)
Animales , Masculino , Perros , Tiña/veterinaria , Trichophyton/aislamiento & purificación , Dermatomicosis/diagnóstico , Dermatomicosis/veterinaria , Técnicas de Diagnóstico Molecular/veterinaria , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinariaRESUMEN
Trichophyton violaceum es un dermatofito antropofílico endémico en África, Europa, Centroamérica y China. El incremento de los fenómenos de movilidad humana ha contribuido a su aparición en áreas no endémicas. Su principal manifestación clínica es la tinea capitis, seguida por la tinea corporis. En la población pediátrica afecta con mayor frecuencia el cuero cabelludo; y en adultos, la piel glabra. Presentamos el primer caso en Chile de tinea causada por T violaceum. Correspondió a una mujer chilena de 21 años que presentó placas faciales de un mes de evolución después de un viaje a Tanzania, África, sin respuesta a tratamientos médicos previos. Se sospechó una dermatofitosis alóctona y mediante cultivos especiales, se identificó una colonia de crecimiento lento, coloración violeta-negruzca, superficie cerosa y rugosa, con vellosidades aterciopeladas; compatible con T violaceum. Se confirmó mediante secuenciación de ADN ribosomal amplificando la región ITS. Se trató con terbinafina oral con respuesta clínica completa.
Trichophyton violaceum is an anthropophilic dermatophyte endemic in Africa, Europe, Central America and China. The increase in human mobility has recently contributed to the appearance in non-endemic areas. The main clinical manifestation is tinea capitis followed by tinea corporis. We present the first case in Chile of tinea caused by T violaceum. The case was a 21 year-old Chilean woman who presented asymptomatic facial plaques one month after arriving from Tanzania, Africa, with no clinical response to previous medical treatments. An allochthonous dermatophytosis was suspected and with special cultures, a slow-growing colony was identified with a violet-blackish color, waxy and rough surface, and velvety villi; all characteristics of T violaceum. The diagnosis was confirmed by ribosomal DNA sequencing amplifying the ITS region. She was treated with oral terbinafine obtaining a complete clinical response.