A Week of Oral Terbinafine Pulse Regimen Every Three Months to Treat all Dermatophyte Onychomycosis.

Terbinafine has proved to treat numerous fungal infections, including onychomycosis, successfully. Due to its liver metabolization and dependency on the cytochrome P450 enzyme complex, undesirable drug interaction are highly probable. Additionally to drug interactions, the treatment is long, rising the chances of the appearance of side effects and abandonment. Pharmacokinetic data suggest that terbinafine maintains a fungicidal effect within the nail up to 30 weeks after its last administration, which has aroused the possibility of a pulse therapy to reduce the side effects while treating onychomycosis. This study's goal was to evaluate the effectiveness of three different oral terbinafine regimens in treating onychomycosis due to dermatophytes. Sixty-three patients with onychomycosis were sorted by convenience in three different groups. Patients from group 1 received the conventional terbinafine dose (250 mg per day for 3 months). Group 2 received a monthly week-long pulse-therapy dose (500 mg per day for 7 days a month, for 4 months) and group 3 received a 500 mg/day dose for 7 days every 3 months, totaling four treatments. There were no statistical differences regarding the effectiveness or side effects between the groups. Conclusion: A quarterly terbinafine pulse regimen can be a possible alternative for treating onychomycosis caused by dermatophytes.

Chemical composition, antioxidant and antifungal activities of essential oils and extracts from Plectranthus spp. against dermatophytes fungi

Resistance to use antifungal drugs is a great concern seeking for scientists to discover new products to treat fungal infections. The aim of this study was to evaluate the antioxidant and antifungal activities of essential oils and extracts of Plectranthus grandis and Plectranthus ornatus against Trichophyton rubrum and Microsporum canis dermatophytes strains. Extracts were obtained from leaves by maceration in ethanol (96%) during 7 days. The oils were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. A total of 25 components were identified, as major constituents the sesquiterpenes β-caryophyllene, α-copaene, germacrene, β-caryophyllene and caryophyllene oxide. Antioxidant activities were evaluated using DPPH scavenging assay and antifungal action was determined by the broth microdilution method. The decocts obtained from the extraction of essential oil presented a greater antioxidant action when compared with the essential oils, with IC50 values of 12.35 μg/mL and 15.69 μg/mL to P. ornatus and P. grandis, respectively. Natural products presented significant antifungal activity, with MIC values ranging from 0.078 mg/mL to 0.31 mg/mL for all strains. The synergistic activity between Plectranthus spp. extracts and ketoconazole demonstrated a fungal growth inhibitory action when combined with a standard antifungal drug, indicating its potential for use in preventive veterinary medicine to treat dermatophytoses.

A resistência ao uso de drogas antifúngicas é uma grande preocupação para os cientistas, que buscam descobrir novos produtos para tratar infecções fúngicas. O objetivo deste estudo foi avaliar as atividades antioxidantes e antifúngicas de óleos essenciais e extratos de Plectranthus grandis e Plectranthus ornatus contra Trichophyton rubrum e Microsporum canis, fungos dermatófitos. Extratos foram obtidos a partir de folhas por maceração em etanol (96%) durante 7 dias. Os óleos essenciais foram obtidos por hidrodestilação e analisados por cromatografia gasosa/espectrometria de massa. Um total de 25 componentes foram identificados, como constituintes principais, os sesquiterpenos β-cariofileno, a-copaene, germacrene, β-cariofileno e óxido de cariofileno. As atividades antioxidantes foram avaliadas usando o teste de eliminação de DPPH e a ação antifúngica foi determinada pelo método de microdiluição de caldo. Os decoctos obtidos a partir da extração de óleo essencial apresentaram uma maior ação antioxidante quando comparados com os óleos essenciais, com valores de IC50 de 12,35 μg/mL e 15,69 μg/mL para P. ornatus e P. grandis, respectivamente. Os produtos naturais apresentaram atividade antifúngica significativa, com valores de MIC variando de 0,078 mg/mL a 0,31 mg/mL para todas as cepas. A atividade de sinergismo entre extratos de Plectranthus spp. e cetoconazol demonstrou uma ação de inibição do crescimento fúngico, quando da combinação com um fármaco antifúngico padrão, indicando seu potencial de uso em medicina veterinária preventiva para tratar dermatofitoses.

Chemical composition, antioxidant and antifungal activities of essential oils and extracts from Plectranthus spp. against dermatophytes fungi

Resistance to use antifungal drugs is a great concern seeking for scientists to discover new products to treat fungal infections. The aim of this study was to evaluate the antioxidant and antifungal activities of essential oils and extracts of Plectranthus grandis and Plectranthus ornatus against Trichophyton rubrum and Microsporum canis dermatophytes strains. Extracts were obtained from leaves by maceration in ethanol (96%) during 7 days. The oils were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. A total of 25 components were identified, as major constituents the sesquiterpenes β-caryophyllene, α-copaene, germacrene, β-caryophyllene and caryophyllene oxide. Antioxidant activities were evaluated using DPPH scavenging assay and antifungal action was determined by the broth microdilution method. The decocts obtained from the extraction of essential oil presented a greater antioxidant action when compared with the essential oils, with IC50 values of 12.35 μg/mL and 15.69 μg/mL to P. ornatus and P. grandis, respectively. Natural products presented significant antifungal activity, with MIC values ranging from 0.078 mg/mL to 0.31 mg/mL for all strains. The synergistic activity between Plectranthus spp. extracts and ketoconazole demonstrated a fungal growth inhibitory action when combined with a standard antifungal drug, indicating its potential for use in preventive veterinary medicine to treat dermatophytoses.(AU)

A resistência ao uso de drogas antifúngicas é uma grande preocupação para os cientistas, que buscam descobrir novos produtos para tratar infecções fúngicas. O objetivo deste estudo foi avaliar as atividades antioxidantes e antifúngicas de óleos essenciais e extratos de Plectranthus grandis e Plectranthus ornatus contra Trichophyton rubrum e Microsporum canis, fungos dermatófitos. Extratos foram obtidos a partir de folhas por maceração em etanol (96%) durante 7 dias. Os óleos essenciais foram obtidos por hidrodestilação e analisados por cromatografia gasosa/espectrometria de massa. Um total de 25 componentes foram identificados, como constituintes principais, os sesquiterpenos β-cariofileno, a-copaene, germacrene, β-cariofileno e óxido de cariofileno. As atividades antioxidantes foram avaliadas usando o teste de eliminação de DPPH e a ação antifúngica foi determinada pelo método de microdiluição de caldo. Os decoctos obtidos a partir da extração de óleo essencial apresentaram uma maior ação antioxidante quando comparados com os óleos essenciais, com valores de IC50 de 12,35 μg/mL e 15,69 μg/mL para P. ornatus e P. grandis, respectivamente. Os produtos naturais apresentaram atividade antifúngica significativa, com valores de MIC variando de 0,078 mg/mL a 0,31 mg/mL para todas as cepas. A atividade de sinergismo entre extratos de Plectranthus spp. e cetoconazol demonstrou uma ação de inibição do crescimento fúngico, quando da combinação com um fármaco antifúngico padrão, indicando seu potencial de uso em medicina veterinária preventiva para tratar dermatofitoses.(AU)

Molecular identification and phylogenetical analysis of dermatophyte fungi from Latin America.

Dermatophytes constitute a complex group of fungi, comprised of by the genera Trichophyton, Epidermophyton and Microsporum. They have the ability to degrade keratin and cause human and animal infections. Molecular techniques have made their identification faster and more accurate, and allowed important advances in phylogenetic studies. We aim to identify molecularly and to determine the phylogenetic relationships in dermatophyte fungi from Brazil and other Latin American countries, using DNA sequencing of the nuclear ribosome regions ITS1-5.8S-ITS2 and D1/D2. DNA of 45 dermatophytes was extracted and amplified by PCR for identification at the species level by sequencing of those ribosomal regions. The software mega 6.0 was used to establish the phylogenetic relationships via the Maximum Likelihood method. Out of 45 strains, 43 were identified by ITS (95.5%) and 100% by D1/D2 sequencing. Two strains could not be identified by ITS. Phylogenetic analyses separated the genera Trichophyton and Microsporum, which presented an uncertain relationship with Epidermophyton floccosum, depending on the ribosomal marker. Both regions can provide efficient identification of dermatophytes, whereas phylogenetic analysis revealed complex relations among dermatophyte fungi.

Case for diagnosis

Majocchi's granuloma is a persistent supurative folliculitis, associated with a deep granulomatous reaction induced by dermatophytes. There are two clinical forms of Majocchi's granuloma: the superficial form that appears in healthy individuals after localized trauma; and the nodular form, which occurs in inmunocompromised patients. We present a case of nodular Majocchi's granuloma on the forearm of an immunocompetent patient. Microbiological culture and examination of a deep aspiration sample identified Trichophyton rubrum. Collecting a deep sample of tissue is essential in achieving a good diagnostic performance.

Identification of fungi species in the onychomycosis of institutionalized elderly / Identificação de espécies fúngicas nas onicomicoses do idoso institucionalizado

BACKGROUND: Superficial fungal infections are caused by dermatophytes, yeasts or filamentous fungi. They are correlated to the etiologic agent, the level of integrity of the host immune response, the site of the lesion and also the injured tissue. OBJECTIVE: The purpose of this study is to isolate and to identify onychomycosis agents in institutionalized elderly (60 years old +). METHODS: The identification of the fungi relied upon the combined results of mycological examination, culture isolation and micro cultures observation under light microscopy from nail and interdigital scales, which were collected from 35 elderly with a clinical suspicion of onychomycosis and a control group (9 elderly with healthy interdigital space and nails). Both groups were institutionalized in two nursing homes in Sao Bernardo do Campo, SP, Brazil. RESULTS: The nail scrapings showed 51.40% positivity. Of these, dermatophytes were found in 44.40% isolates, 27.78% identified as Trichophyton rubrum and 5.56% each as Trichophyton tonsurans, Trichophyton mentagrophytes and Microsporum gypseum. The second more conspicuous group showed 38.89% yeasts: 16.67% Candida guilliermondii, 11.11% Candida parapsilosis, 5.56% Candida glabrata, and 5.56% Trichosporon asahii. A third group displayed 16.70% filamentous fungi, like Fusarium sp, Aspergillus sp and Neoscytalidium sp (5.56% each). The interdigital scrapings presented a positivity rate of 14.29%. The agents were coincident with the fungi that caused the onychomycosis. In the control group, Candida guilliermondii was found at interdigital space in one person. CONCLUSION: Employing a combination of those identification methods, we found no difference between the etiology of the institutionalized elderly onychomycosis from that reported in the literature for the general population. .

FUNDAMENTOS: As infecções fúngicas superficiais se correlacionam com o agente etiológico, a resposta imune do hospedeiro, o local da lesão e o tecido lesado, sendo causadas por dermatófitos, leveduras ou fungos filamentosos. OBJETIVO: O objetivo é isolar e identificar os agentes das onicomicoses em idosos institucionalizados. MÉTODO: A identificação dos fungos baseou-se nos resultados combinados do exame micológico, isolamento em cultura e da observação de microculturas sob microscopia de luz, do material subungueal e escamas interdigitais, coletado de 35 idosos com suspeita clínica de onicomicose e de um grupo controle (9 idosos com espaço interdigital e unhas saudáveis). Ambos os grupos eram institucionalizados em duas casas de assistência em São Bernardo do Campo, SP, Brasil. RESULTADOS: As unhas raspadas apresentaram 51,40% de positividade. Os dermatófitos foram encontrados em 44,40% de isolados, sendo 27,78% identificados como Trichophyton rubrum e 5,56%, cada, como Trichophyton tonsurans, Trichophyton mentagrophytes e Microsporum gypseum. O segundo grupo mais frequente (38,89%) foi o de leveduras, identificadas como 16,67% Candida guilliermondii, 11,11% Candida parapsilosis, 5,56% Candida glabrata e 5,56% Trichosporon asahii. Um terceiro grupo exibia 16,70% fungos filamentosos, como Fusarium sp, Aspergillus sp e Neoscytalidium (5,56% de cada). Os raspados interdigitais exibiram positividade de 14,29%. Os agentes foram coincidentes com os fungos que causaram a onicomicose. No grupo controle, a Candida guilliermondii foi identificada no espaço interdigital em apenas uma pessoa. CONCLUSÃO: Empregando-se a combinação destes métodos de identificação, não houve diferença entre a etiologia da onicomicose ...

Genetic variability in Microsporum canis isolated from cats, dogs and humans in Brazil.

Dermatophytosis caused by Microsporum canis is a heterogeneous disease with variable clinical manifestations. M. canis is a zoophilic dermatophyte and the most frequent fungi isolated from dogs, cats and children in Brazil. The aim of this study was to investigate the genetic variability of M. canis isolates from different animal species using two microsatellite markers, namely, McGT(13) and McGT(17), and to correlate the results with the clinical and epidemiological patient data in Brazil. The study included a global set of 102 M. canis strains, including 37 symptomatic cats, 35 asymptomatic cats, 19 human patients with tinea, 9 asymptomatic dogs and 2 symptomatic dogs. A total of 14 genotypes were identified, and 6 large populations were distinguished. There was no correlation between these multilocus genotypes and the clinical and epidemiological data, including the source, symptomatology, clinical picture, breed, age, sex, living conditions and geographic location. These results demonstrate that the use of microsatellite polymorphisms is a reliable method for the differentiation of M. canis strains. However, we were unable to demonstrate a shared clinical and epidemiological pattern among the same genotype samples.

Factores de virulencia para lainfección de tejidos queratinizadospor Candida albicans y hongosdermatofitos / Virulence factors of Candida albicans and dermatophytes in keratinized tissues infection

Los hongos C. albicans y los dermatofitos tienen características especiales que les confierenla habilidad de infectar tejido queratinizado. C. albicans es un comensal que en algunascircunstancias y en el hospedero susceptible es capaz de causar infecciones superficiales o sistémicas.Los factores de virulencia de este patógeno oportunista incluyen: su capacidad de adherencia alhospedero, la secreción de enzimas degradativas, su cambio de morfología y la formación de biopelículas.Los dermatofitos son la causa más común de infección de la piel, la cual logran infectarpor factores de virulencia como la adherencia y la invasión de tejidos queratinizados. Conocer aprofundidad los factores de virulencia puede ayudar en la elaboración de terapias dirigidas y eficacesfrente a ellos. A continuación se presentan una revisión de la literatura de los factores de virulenciade C. albicans y los dermatofitos.

C. albicans and dermatophytes have special characteristicsthat confer them the ability to infectkeratinized tissues. C. albicans is part of the human flora but under some circumstances andin susceptible individuals it can cause systemic and superficial infections. Virulence factors ofthis opportunist include: its capacity to adhere to the host, secretion of degradation enzymes,its ability to change morphologically and to form biofilms. Dermatophytes are the most common cause of skin infection and they can achieve thisdue to virulence factors such as their ability to adhere and invade keratinized tissues. To knowand understand in depth the virulence factors of these fungi might to find further direct therapiesin a more efficacious way. We present a literature review about the virulence factors of C. albicans and dermatophytes.

Perfil de suscetibilidade a antifúngicos de dermatófitos isolados de pacientes com insuficiência renal crônica / Antifungal susceptibility of dermatophytes isolated from patients with chronic renal failure

FUNDAMENTOS: As dermatofitoses apresentam alta prevalência na população em geral e, principalmente, em pacientes com insuficiência renal crônica, necessitando tratamento com antifúngicos tópicos e/ou sistêmicos, cuja eficácia precisa ser avaliada. Estudos in vitro para avaliar a ação de antifúngicos são raros, especialmente, em fungos filamentosos. OBJETIVO: Avaliar o perfil de suscetibilidade de diferentes espécies de dermatófitos, isolados de pacientes com insuficiência renal crônica, em relação a nove antifúngicos disponíveis comercialmente para o tratamento de dermatofitoses. MÉTODO: Analisaram-se 26 isolados de dermatófitos de pacientes com insuficiência renal crônica em relação a nove antifúngicos (cetoconazol, ciclopirox olamina, fluconazol, griseofulvina, itraconazol, miconazol, piroctona olamina, terbinafina e tioconazol) pelo método de microdiluição em caldo proposto pelo Clinical and Laboratory Standards Institute (CLSI), com modificações para dermatófitos. RESULTADOS: Entre os antifúngicos testados, a terbinafina e o tioconazol obtiveram os melhores resultados de sensibilidade e o fluconazol apresentou baixa atividade, especialmente para as amostras da espécie M. gypseum. O ciclopirox olamina, apesar de menos eficaz que a terbinafina, também mostrou resultados satisfatórios. CONCLUSÕES: De modo geral, o perfil de sensibilidade dos antimicóticos testados seguiu o padrão de resultados mostrados por estudos anteriores, ratificando a necessidade de conhecimento da espécie causadora de dermatofitose, devido à variação do perfil de suscetibilidade entre as espécies. Além disso, nossos resultados demonstram a importância da realização de ensaios de sensibilidade in vitro, pois alguns isolados da mesma espécie apresentaram diferente perfil de sensibilidade.

BACKGROUND: The prevalence of dermatophytosis in the general population is high, particularly in patients with chronic renal failure. Treatment requires the use of topical and/or systemic antifungal drugs. The efficacy of antifungal agents for the treatment of dermatophytosis has yet to be evaluated. Studies evaluating the in vitro activity of antifungal agents are rare, particularly in filamentous fungi. OBJECTIVE: To evaluate the susceptibility profile of different species of dermatophytes isolated from patients with chronic renal failure to nine antifungal drugs available on the market for the treatment of dermatophytosis. METHODS: Twenty-six isolates of dermatophytes obtained from patients with chronic renal failure were analyzed with respect to their susceptibility to nine antifungal agents (ketoconazole, ciclopirox olamine, fluconazole, griseofulvin, itraconazole, miconazole, piroctone olamine, terbinafine and tioconazole), using the broth microdilution method proposed by the Clinical and Laboratory Standards Institute (CLSI) and adapted for dermatophytes. RESULTS: Of the antifungal agents tested, the best results in terms of sensitivity were found with terbinafine and tioconazole, while the antifungal activity of fluconazole was found to be weak, particularly against strains of M. gypseum. Ciclopirox olamine, although less effective than terbinafine, also yielded satisfactory results. CONCLUSIONS: In general, the sensitivity profile of the antifungal agents tested in this study was similar to results obtained in previous studies, confirming the need to determine which species is causing the dermatophytosis given that antifungal susceptibility varies from one species to another. Furthermore, the present findings show the importance of conducting in vitro sensitivity tests, since the sensitivity profile may differ among isolates of the same species.

Avaliação do método de disco-difusão para determinação da eficácia da terbinafina in vitro em agentes de micoses superficiais e subcutâneas / Evaluation of the disk-diffusion method to determine the in vitro efficacy of terbinafine against subcutaneous and superficial mycoses agents

FUNDAMENTOS: As micoses superficiais e subcutâneas têm alta prevalência e, muitas vezes, caráter crônico, necessitando tratamentos tópicos e/ou sistêmicos com antifúngicos. As drogas de escolha são azóis e alilaminas (terbinafina). É necessário avaliar a eficácia das drogas para tratamento em humanos e em animais. Estudos para avaliar in vitro a ação dos antimicóticos são raros, especialmente, contra fungos filamentosos. OBJETIVO: Avaliar a eficácia in vitro da terbinafina pelo método de disco-difusão contra fungos filamentosos e leveduras agentes de micoses. MÉTODOS: Avaliou-se a ação da terbinafina (0,125µg-100µg) contra dez espécies fúngicas pelos métodos discodifusão e microdiluição/referência, para determinar a concentração inibitória mínima (MIC). RESULTADOS: Observou-se alta sensibilidade à terbinafina em: T. rubrum, M. gypseum, T. mentagrophytes, T. tonsurans, M. canis, C. carrionii e E. floccosum (halo ≥ 40mm com disco de 0,125µg). S. hyalinum e C. parapsilosis foram considerados sensíveis, mas com halos menores. Fusarium spp. apresentou menor sensibilidade (halo=12mm com disco de 2µg; MIC 8µg/mL). CONCLUSÕES: Os resultados reiteram estudos anteriores quanto à alta eficácia da terbinafina em relação a dermatófitos. A técnica de disco-difusão foi de fácil aplicação e adequada na rotina de laboratórios clínicos.

BACKGROUND: Superficial and subcutaneous mycoses have a high prevalence and, often, chronic evolution. Therefore, they need extensive treatment with topic and/or systemic antifungal agents. Azoles and alilamines (terbinafine) are first-choice drugs to treat human and animal infections. Thus, evaluation of the efficacy of these drugs is important for a successful treatment. However, there are few studies that evaluate the in vitro activity of antifungal agents. OBJECTIVE: To evaluate the in vitro efficacy of terbinafine activity against filamentous fungi and yeasts that cause mycoses. METHOD: The in vitro activity of terbinafine (0.125-100µg) against 10 fungi species was evaluated by the diskdiffusion and microdilution/reference methods to determine the Minimum Inhibitory Concentration (MIC). RESULTS: We found a high susceptibility to terbinafine in: T. rubrum, M. gypseum, T. mentagrophytes, T. tonsurans, M. canis, C. carrionii and E. floccosum (halo ≥ 40mm with 0.125µg disk). S. hyalinum and C. parapsilosis were considered susceptible, but less than the others. Fusarium spp. showed the lowest susceptibility (halo=12mm with 2µg disk; MIC 8µg/mL). CONCLUSIONS: The results of this research confirm previous findings about the efficacy of terbinafine. The drug was shown to be highly effective to treat dermatophyte infections. The disk-diffusion method was easy to use and is a suitable technique for routine use in clinical laboratories.

Resposta in vitro de fungos agentes de micoses cutâneas frente aos antifúngicos sistêmicos mais utilizados na dermatologia / In vitro response of cutaneous mycosis fungal agents to the most widely used systemic antifungals in dermatology

FUNDAMENTOS - A alta frequência das micoses cutâneas justifica a necessidade de avaliar a possível contribuição da determinação do perfil de susceptibilidade aos antifúngicos in vitro. OBJETIVO - Avaliar se existe variabilidade nos isolados fúngicos quanto à susceptibilidade in vitro de fungos filamentosos, previamente isolados de micoses cutâneas, frente aos antifúngicos fluconazol, cetoconazol, itraconazol e terbinafina. MÉTODOS - Os fungos foram isolados e identificados por meio da metodologia clássica e o teste de susceptibilidade aos antifúngicos foi realizado segundo o método de microdiluição em caldo, de acordo com protocolo preconizado pelo Clinical Laboratory Standards Institute (CLSI), documento M38-A. RESULTADOS - Das 80 amostras de fungos filamentosos identificadas, o gênero Trichophyton representou 81 por cento. As quatro drogas analisadas apresentaram grande variação nos gêneros Trichophyton e Microsporum. O gênero Fusarium foi resistente a todas as drogas testadas. A terbinafina foi o antimicótico mais eficaz contra a maioria dos isolados fúngicos. CONCLUSÃO - Houve uma grande variabilidade nos perfis de resposta aos antifúngicos testados. O estabelecimento de um método-teste de referência permitirá ao clínico maior objetividade na escolha de uma terapia adequada.

BACKGROUND - The high frequency of cutaneous mycosis justify the need to evaluate the possible contribution of in vitro profile of susceptibility to antifungal agents. OBJECTIVE - To evaluate whether there is variability in in vitro susceptibility by filamentous fungi, previously isolated from cutaneous mycosis, to fluconazole, ketoconazole, itraconazole and terbinafine. METHODS - Fungi were isolated and identified by classical methods and the antifungal susceptibility test was performed using the method of broth microdilution, according to a protocol recommended by the Clinical Laboratory Standards Institute (CLSI), through M38-A document. RESULTS - Amongst the 80 filamentous fungi identified, Trichophyton genus represented 81 percent. The four examined drugs showed great variation for Trichophyton spp and Microsporum spp. Fusarium spp was resistant to all tested drugs. Terbinafine was the most effective drug against the majority of the isolated fungi. CONCLUSION - There was great variability in response profiles to the tested antifungals. The definition of a reference test method will offer higher objectivity for physicians to choose the appropriate therapy.