In vitro sensitivity of Malassezia furfur isolates from HIV-positive and negative patients to antifungal agents / Sensibilidad in vitro a antifúngicos de aislamientos de Malassezia furfur de pacientes positivos y negativos para HIV

Introduction. Malassezia is a lipophilic and lipid-dependent yeast genus belonging to the skin microbiota of humans and other animals. However, due to dysbiosis processes or other factors in the host, this yeast can cause different pathologies, ranging from skin diseases, such as seborrheic dermatitis, to fungemia. Isolation of Malassezia furfur has been reported in HIV-positive patients with or without skin lesions. Due to its opportunistic nature and its variable resistance to antifungal compounds, it is relevant to know the Malassezia sensitivity profiles. Objective. To determine the sensitivity to different antifungal agents, of clinical isolates of M. furfur obtained from HIV-positive or negative patients, with or without seborrheic dermatitis. Materials and methods. Assessment of isolates sensitivity to itraconazole, voriconazole, fluconazole, and amphotericin B was performed by two techniques: (1) Broth microdilution using Clinical and Laboratory Standards Institute (CLSI) protocol M27-A3 with modifications; and (2) agar tests using Etest®. Results. Isolates obtained from HIV patients showed an increase in the minimum inhibitory concentration of fluconazole, voriconazole, and amphotericin B, compared with those of non-HIV patients. Itraconazole was the antifungal with the lowest minimum inhibitory concentration (MIC) in most isolates. Conclusion. We observed differences in the sensitivity profiles of M. furfur isolates according to the context of the patient. High MIC of antifungals like fluconazole, commonly used for treating pathologies caused by Malassezia, were identified.

Introducción. Malassezia es un género de levaduras lipofílicas que dependen de los lípidos y hacen parte de la microbiota de la piel de humanos y otros animales. No obstante, debido a procesos de disbiosis u otros factores en el huésped, esta levadura puede llegar a causar diferentes enfermedades: desde cutáneas (como dermatitis seborreica) hasta fungemias. Se han reportado aislamientos de Malassezia furfur en pacientes positivos para HIV, con lesiones cutáneas o sin ellas. Por su carácter oportunista y sensibilidad variable a los compuestos antifúngicos, es relevante conocer los perfiles de sensibilidad. Objetivo. Determinar la sensibilidad a diferentes antifúngicos de aislamientos clínicos de M. furfur obtenidos de pacientes positivos o negativos para HIV, con dermatitis seborreica o sin ella. Materiales y métodos. La sensibilidad de los aislamientos a itraconazol, voriconazol, fluconazol y anfotericina B, se determinó mediante dos técnicas: microdilución en caldo según el protocolo M27-A3 del Clinical & Laboratory Standards Institute (CLSI), con modificaciones, y pruebas en agar mediante Etest®. Resultados. Los aislamientos obtenidos de pacientes con HIV mostraron aumento de la concentración inhibitoria mínima a fluconazol, voriconazol y anfotericina B, en comparación con los de pacientes sin HIV. Por otro lado, al evaluar la mayoría de los aislamientos, el itraconazol fue el antifúngico con la menor concentración inhibitoria mínima. Conclusión. Se evidencian diferencias en los perfiles de sensibilidad de los aislamientos de M. furfur, según el contexto del paciente, y elevadas concentraciones inhibitorias mínimas de antifúngicos como el fluconazol, usados comúnmente para el tratamiento de las enfermedades causadas por Malassezia spp.

Homeopathy treatment of Malassezia Pachydermatis in vitro

A common clinical occurrence in dogs is otitis externa caused by excessive growth of yeasts Malassezia pachydermatis, which can become chronic after wrong treatments, in which microbial resistance can occur. Homeopathic remedies can be considered a successful alternative, selecting the medicine through the similitude principle. Herein, 50 µL of a 1:1000 dilution of Malassezia pachydermatis suspension at 0.5 McFarland scale was used to seed the yeast into Sabouraud dextrose agar plates using a Drigalski spreader to proceed with colony unit counting. Before being seeded, the yeast suspensions were treated with 1% of different homeopathic treatments previously selected from a pilot study, which means Sulphur 6cH, Dolichos pruriens 6cH, and Kali carbonicum 6cH, being water, and succussed water used as controls. For comparison, a set of Sabouraud dextrose agar plates containing 1% Tween 80 was seeded in parallel. The treatments were made blind and evaluated in triplicate. Contaminated cultures were withdrawn. The number of colonies per plate was assessed, and smears were made from the cultures to classify yeast growth according to cytomorphology on ImageJ®software. The preliminary results show no significant effect of all tested medicines compared to the controls. High data variability was also observed, mainly in those cultures whose medium was prepared with Twin 80. In conclusion, at this point of the study, no evidence of the effects of the studied medicines on Malassezia pachydermatis growth in vitro could be identified. The analysis of cytomorphology is still in course.

Prevalence of sensitization to Malassezia spp. in adults with atopic dermatitis and psoriasis and its correlation with disease severity / Prevalência da sensibilização a Malassezia spp. em pacientes adultos portadores de dermatite atópica e psoríase e sua correlação com a gravidade das doenças

Fundamentals: Atopic Dermatitis (AD) and Psoriasis (PS) share clinical and physiopathological similarities. Objective: Determine the prevalence of sensitization to Malassezia spp. in adults with AD and PS and its correlation with disease severity. Methods: A cross-sectional study was carried out from January 2016 to August 2017 with adults. Malassezia spp.-specific IgE dosages were measured, and skin scrapings for fungal culture performed. Parametric or nonparametric tests were used for analysis. Results: Median age of the 20 participants with AD was 29 years old, and the mean SCO-RAD was 45.35 ± 18.32. Malassezia spp.- specific IgE median dosage was 0.63 kU/l. M. furfur and M. sympodialis were isolated. Spearman's nonparametric correlation analysis showed no correlation between sensitization to Malassezia spp. and disease severity. The median age of the 36 participants with PS was 61 years old, the median body surface area affected was 22%, and Malassezia spp.-specific IgE median dosage was 0.00 kU/l. M. furfur and Malassezia spp. were identified. Study limitations: Assessing the sensitization to Malasseziaspp. was difficult due to the reduced number of participants in the study. Furthermore, there was no uniformity in the location to collect skin scrapings. The use of topical medication was not suspended before collecting skin specimens for mycological examination, therefore interfer-ing with fungal isolation. Conclusion: Sensitization to Malassezia spp. was only detected in the AD sample. Malassezia spp.-specific IgE test did not prove to be a marker for disease severity in our AD sample (AU)

Fundamentos: Dermatite atópica (DA) e psoríase apresentam similaridades clínicas e fisiopatológicas. Objetivos: Avaliar a frequência da sensibilização a Malasseziaspp. em adultos portadores de DA e psoríase e correlacionar à gra-vidade dos quadros clínicos. Métodos: De janeiro de 2016 a agosto de 2017, conduziu-se um estudo observacional em indivíduos adultos onde foram realizadas dosagem de IgE específica anti-Malassezia spp. e raspados das lesões para cultura micológica. Testes paramétricos ou não paramétricos foram utilizados para análise. Resultados: Nos 20 portadores de DA, a mediana da idade foi 29 anos. O valor médio do Scoring Atopic Dermatitis foi 45,35 ± 18,32. A mediana de IgE específica anti-Malasseziaspp. foi 0,63 kU/l. M. furfur e M. sympodialis foram isolados. A análise de correlação não-paramétrica de Spearman não mostrou correlação entre a sensibilização à Malassezia spp. e a gra-vidade. Nos 36 pacientes com psoríase, foram obtidas as seguintes medianas: idade 61 anos, comprometimento de superfície corpórea 22% e IgE específica anti-Malassezia spp. 0,00 kU/l. Houve identificação de M. furfur e Malasse-zia spp. Limitações do estudo: O número reduzido de participantes dificultou a avaliação da sensibilização por IgE a Malasseziaspp. Não houve uniformidade nos locais de coleta dos raspados cutâneos. Medicamentos tópicos não foram suspensos anteriormente ao exame micológico, prejudicando o isolamento dos fungos. Conclusões: Sensibili-zação a Malassezia spp. apenas ocorreu nos portadores de DA. O teste de IgE específica anti-Malassezia spp. não se mostrou um marcador de gravidade para a DA neste grupo (AU)

The correct nomenclature of Zirelí sign in the propaedeutics of pityriasis versicolor (in memoriam)

Abstract Aiming at disclosing the semiotic method used in the diagnosis of pityriasis versicolor, the authors go through the history of the creation of Zirelí sign, describing the method, its usefulness and practicality in dermatological clinical practice, whether public or private, and to give credit to the author of this semiological maneuver, in memoriam.

Seborrheic dermatitis and its relationship with Malassezia spp / Dermatitis seborreica y su relación con Malassezia spp

Abstract Seborrheic dermatitis (SD) is a chronic inflammatory disease that that is difficult to manage and with a high impact on the individual's quality of life. Besides, it is a multifactorial entity that typically occurs as an inflammatory response to Malassezia species, along with specific triggers that contribute to its pathophysiology. Sin ce the primary underlying pathogenic mechanisms include Malassezia proliferation and skin inflammation, the most common treatment includes topical antifungal keratolytics and anti-inflammatory agents. However, the consequences of eliminating the yeast population from the skin, the resistance profiles of Malassezia spp. and the effectivity among different groups of medications are unknown. Thus, in this review, we summarize the current knowledge on the disease´s pathophysio logy and the role of Malassezia sp. on it, as well as, the different antifungal treatment alternatives, including topical and oral treatment in the management of SD.

Resumen La dermatitis seborreica (DS) es una enfermedad inflamatoria crónica, con un elevado impacto en la calidad de vida del individuo. Además, DS es una entidad multifactorial que ocurre como respuesta inflamatoria a las levaduras del género Malassezia spp., junto con factores desencadenantes que contribuyen a la fisio patología de la enfermedad. Dado que el mecanismo patogénico principal involucra la proliferación e inflamación generada por Malassezia spp., el tratamiento más usado son los agentes tópicos antifúngicos y antiinflamatorios. Sin embargo, se desconocen las consecuencias de eliminar la población de levaduras de la piel, los perfiles de resistencia de Malassezia spp. y la efectividad entre grupos diferentes de medicamentos. Por tanto, en esta revisión de la literatura, resumimos el conocimiento actual sobre la fisiopatología de la enfermedad y el papel de Malassezia sp., así como de las diferentes alternativas de tratamiento antifúngico tanto tópico como oral en el manejo de la DS.

Fungemia por Malassezia sympodialis en una Unidad de Cuidados Intensivos Neonatal de Colombia / Fungemia by malassezia sympodialis in a neonatal intensive care unit in Colombia

Resumen El género Malassezia comprende levaduras lipofílicas, comensales de la piel de humanos y animales, responsables de infecciones dermatológicas y sistémicas, particularmente en recién nacidos pretérmino hospitalizados en Unidades de Cuidados Intensivos Neonatal (UCIN) con catéteres venosos centrales, antibióticos de amplio espectro y nutrición parenteral rica en lípidos. La información acerca de las fungemias por este microorganismo es limitada, sin embargo, la mayoría de infecciones invasivas reportadas en la literatura han sido asociadas con M. furfur y M. pachydermatis. Se reporta un caso de fungemia por M. sympodialis en un recién nacido pretérmino hospitalizado en la UCIN de un hospital colombiano con sospecha clínica de sepsis neonatal, antibioticoterapia de amplio espectro y hemocultivos de rutina negativos. El aislamiento fue susceptible a fluconazol y voriconazol, y resistente a anfotericina B. Existen pocos reportes de fungemia producida por M. sympodialis, pero todos concuerdan en que es una levadura subestimada en individuos con factores predisponentes.

Abstract The genus Malassezia comprises lipophilic yeasts, commensals of the skin of humans and animals, responsible for dermatological and systemic infections, particu larly in preterm infants hospitalized in Neonatal Intensive Care Units (NICU) with central venous catheters, broad-spectrum antibiotics and parenteral nutrition rich in lipids. Information about fungemia by this microorganism is limited, however, the majority of invasive infections reported in the literature have been associated with M. furfur and M. pachydermatis. A case of M. sympodialis fungemia is reported in a preterm newborn hospitalized in the NICU of a Colombian hospital with clinical suspicion of neonatal sepsis, broad-spectrum antibiotic therapy and negative routine blood cultures. The isolation was susceptible to fluconazole and voriconazole, and resistant to amphotericin B. There are few reports of fungemia produced by M. sympodialis, but all agree that it is an underestimated yeast in individuals with predisposing factors.

Características clínico-epidemiológicas de los pacientes con pitiriasis versicolor en un centro de referencia de Colombia / Clinical-epidemiological characteristics of patients with tinea versicolor in a Colombian reference center

Resumen Objetivo: describir las características socio-demográficas, presentación clínica y condiciones extrínsecas que pueden favorecer el desarrollo de la pitiriasis versicolor. Material y métodos: estudio observacional descriptivo, de corte transversal y prospectivo, en el que se incluyeron pacientes con diagnóstico clínico y micológico de pitiriasis versicolor entre enero y diciembre de 2018, que asistieron al Hospital Universitario Centro Dermatológico Federico Lleras Acosta. Resultados: se incluyeron un total de 42 pacientes con diagnóstico de pitiriasis versicolor confirmado por examen directo, el 62% fueron hombres con una edad promedio de 33 años. La localización más común fue el tórax anterior (68%) y posterior (65%), en fototipos III y IV (78.5%), con una tonalidad hipocrómica. El 28% presentaron cuadros recurrentes, con síntomas hasta 7 años antes de la consulta. El signo de Besnier fue positivo en el 95% de los casos. El 64% refirió antecedente personal de hiperhidrosis y el 67% practicaba algún deporte como buceo, natación o gimnasia. Discusión: la identificación de las condiciones extrínsecas presentes esta población permite orientar medidas de prevención para evitar recurrencias de pitiriasis versicolor. Los viajes a lugares de clima cálido y la práctica de deportes son factores que favorecen el desarrollo de la micosis. En las formas clínicas atípicas se sugiere realizar siempre el examen micológico directo para confirmar el diagnóstico. El signo de Besnier es una maniobra útil para el diagnóstico clínico de la pitiriasis versicolor, particularmente cuando el acceso al examen directo es limitado.

Abstract Objective: to describe the sociodemographic aspects, clinical presentation and extrinsic conditions that may increase the risk of developing pityriasis versicolor. Materials and methods: a descriptive, cross-sectional and prospective observational study was conducted. Patients with clinical and mycological diagnosis of ptyriasis versicolor were included from january to december 2018 who attended to the Hospital Universitario Centro Dermatológico Federico Lleras Acosta. Results: a total of 42 patients were included in the study, all of them had confirmed mycological diagnosis of pityriasis versicolor. The most common location of the lesions was the anterior thorax (68%) and posterior thorax (65%), in III and IV phototypes (78.5%) with a hypochromic color. 28% had recurrent infection, with symptoms mean of 7 years before the consultation. The Besnier sign was positive in 95% of cases, 64% reported personal history of hyperhidrosis and 67% practiced some sports: diving, swimming and gymnastics. Discussion: recognizing extrinsic conditions that may increase the risk of developing pitiraisis versicolor in this population allows identifying control measures to prevent a relapse. The main factors involved in the development of pitiraisis versicolor were traveling to places with high temperatures and sport practice. In atypical clinical presentation it is mandatory to perform the mycological direct test to confirm the diagnosis. The Besnier sign is a useful method for the clinical diagnosis of pityriasis versicolor, particularly when access to direct examination is limited.

Los restos de Malassez, vida y destino en los tejidos odontogénicos. Una revisión de la literatura / The remains of Malassez life and fate in the odontogenic tissues. A review of the kiterature

Los restos epiteliales de Malassez son células que se encuentran alrededor de las raíces de las piezas dentarias y forman parte de los tejidos del ligamento periodontal, donde se disponen en forma de red. Las funciones que desempeñan no son muy específicas; sin embargo, se demostró su participación en el mantenimiento del espacio del ligamento periodontal, la regeneración del tejido periodontal, la regeneración del cemento, entre otros. Además, tienen capacidad de diferenciarse en otros linajes celulares, lo que demuestra su capacidad como células madres, y el papel más conocido que tienen es su participación y proliferación en la formación de diversas patologías, como quistes y tumores odontogénicos. (AU)

Epithelial rests of Malassez are cells that are arranged in a network located around the roots of the teeth forming part of the periodontal ligament tissues. The functions that these cells perform are not very specific, however, they have shown to participate in the maintenance of the periodontal ligament space, regeneration of periodontal tissue, including cement regeneration among others. In addition, they are able to differentiate into other cell lineages, thereby demonstrating their capacity as stem cells. These cells are best known for their role in the participation and proliferation of the formation of different pathologies, such as cysts and odontogenic tumors. (AU)

Especies de Malassezia causantes de pitiriasis versicolor en Paraguay / Malassezia species causative of pityriasis versicolor in Paraguay

Resumen Introducción: La pitiriasis versicolor es una patología frecuente en Paraguay; sin embargo, su epidemiologia es desconocida. Objetivo: Determinar la frecuencia de especies de Malassezia causantes de pitiriasis versicolor y las características epidemiológicas de la población. Materiales y Métodos: Se recolectaron muestras de pacientes con diagnóstico presuntivo de pitiriasis versicolor. El diagnóstico de laboratorio se realizó mediante examen en fresco y cultivo en agar Dixon modificado y agar cromogénico Chromagar Malassezia®, incubados a 32°C; y la identificación por las características macro y micromorfológicas, pruebas bioquímicas y fisiológicas. Resultados: Se incluyeron 102 pacientes (51% femenino), de 1 mes a 63 años de edad, predominando el grupo de 11 a 20 años (35,3%). La localización más frecuente fue el dorso (60,8%). Predominaron las formas hipocrómicas (48%). La especie más frecuente fue M. globosa (52,9%), seguida de M. furfur (24,5%), M. sympodialis (18,6%) y M. slooffiae (6,9%). Conclusiones: La epidemiología observada es similar a otros estudios sudamericanos, no hace distinción de sexo, se presenta predominantemente en la forma clínica hipocrómica y M. globosa aparece como principal responsable. Este es el primer reporte sobre las especies causantes de pitiriasis versicolor en Paraguay y las características de la población con esta patología.

Background: Pityriasis versicolor is a frequent pathology in Paraguay; however, its epidemiology is unknown. Aim: To determine the frequency of Malassezia species causing pityriasis versicolor and the epidemiological characteristics of the population. Methods: Samples from patients with a presumptive diagnosis of pityriasis versicolor were collected. Laboratory diagnosis was carried out by fresh examination and culture in modified Dixon agar and chromogenic Chromagar Malassezia®, incubated at 32° C, and identification by macro and micromorphological features, biochemical and physiological tests. Results: 102 patients were included (51% female) from 1 month to 63 years of age, the predominant age group was 11-20 years (35.3%). The most frequent location was on the back (60.8%). Hipocromic clinical forms (48%) predominated. The most frequent species was M. globosa (52.9%), followed by M. furfur (24.5%), M. sympodialis (18.6%) and M. slooffiae (6.9%). Conclusions: The observed epidemiology is similar to other South American studies, with no sex distinction, predominantly hypochromic clinical form and as primary responsible species appears M. globosa. This is the first report on species causing pityriasis versicolor in Paraguay and the characteristics of the affected population.

Genotyping of Malassezia pachydermatis disclosed genetic variation in isolates from dogs in Colombia / Genotipagem de Malassezia pachydermatis revelou variação genética em isolados de cães na Colômbia

Malassezia pachydermatis is a lipophilic and lipid-dependent yeast mostly isolated from animals' skin; hence, it is regarded as a zoophilic species causing otitis externa in dogs. Aspects associated with its epidemiology and pathogenicity is a matter of interest. This study aimed to conduct a molecular characterization of 43 isolates of M. pachydermatis obtained from dogs with otitis externa. For this purpose, the 5.8S internal transcribed spacer 2 (ITS2) and D1/D2 26S rRNA regions were amplified, sequenced and analyzed using restriction fragment length polymorphism (RFLP) with AluI, CfoI, and BstF5I endonucleases. Phylogenetic analyses revealed that these isolates grouped with the sequence types I, IV and V, previously proposed for M. pachydermatis. Interestingly, we found a new polymorphic RFLP pattern using BstF5I, these isolates were associated with the sequence types IV and V, nevertheless an association between polymorphic RFLP patterns, and fosfolipase activity or canine population data was not observed. These findings underline the genetic diversity of M. pachydermatis and provide new insights about the epidemiology of this species in the analyzed population.(AU)

Malassezia pachydermatis é uma levedura lipofílica e dependente de lipídios, principalmente da pele de animais. Sendo, por essa razão, considerada uma espécie zoofílica e causadora de otite externa em cães. Neste sentido, aspectos associados à sua epidemiologia e patogenicidade constituem um tema de interesse científico. O objetivo deste estudo foi realizar a caracterização molecular de 43 isolados de M. pachydermatis obtidos a partir de cães com otite externa. Para esta propósito, foram amplificadas, sequenciadas e analisadas com enzimas de restrição as regiões do gene 5.8S, do espaçador interno transcrito 2 (ITS2) e D1/D2 do 26S do rRNA pelo método RFLP, com as endonucleases AluI, CfOI e BstF5I. Análises filogenéticas revelaram que os isolados se agruparam com as sequências tipo I, IV e V de M. pachydermatis como já descrito anteriormente. De maneira interessante, se observou um novo RFLP polimórfico utilizando BstF5I. Os isolados que mostraram esse padrão foram associados com os padrões IV e V. No entanto, não foi observada associação entre padrões polimórficos de RFLP e atividade de fosfolipase ou dados da população canina. Estes resultados demonstram a diversidade genética de M. pachydermatis e fornecem novas perspectivas sobre a epidemiologia destas espécies na população analisada.(AU)

Isolation of Malassezia spp. in HIV-positive patients with and without seborrheic dermatitis

Abstract Background Malassezia, a skin saprophyte, is frequently isolated from patients with seborrheic dermatitis, which is one of the most common dermatoses in HIV-infected patients. Its role in pathophysiology has not been defined. Objective To determine whether patients living with HIV and seborrheic dermatitis have more Malassezia than those without seborrheic dermatitis. Method This is an descriptive, observational, prospective cross-sectional study to which all adult patients living with HIV that attend the infectious disease outpatient clinic at the Dr. Manuel Gea González General Hospital were invited. Patients presenting with scale and erythema were included in Group 1, while patients without erythema were included in Group 2. Samples were taken from all patients for smear and culture. Results Thirty patients were included in each group. All patients with seborrheic dermatitis had a positive smear, with varying amounts of yeasts. In the control group, 36.7% of patients had a negative smear. The results are statistically significant, as well as the number of colonies in the cultures.Study limitations The study used a small sample size and the subspecies were not identified. Conclusions Patients with clinical manifestations of seborrheic dermatitis have larger amounts of Malassezia. Further studies need to be performed to analyze if the greater amount is related to imbalances in the microbiota of the skin.

First Case of Catheter-related Malassezia pachydermatis Fungemia in an Adult

No abstract available.

Antifungal Mechanism of Action of Lauryl Betaine Against Skin-Associated Fungus Malassezia restricta

Betaine derivatives are considered major ingredients of shampoos and are commonly used as antistatic and viscosity-increasing agents. Several studies have also suggested that betaine derivatives can be used as antimicrobial agents. However, the antifungal activity and mechanism of action of betaine derivatives have not yet been fully understood. In this study, we investigated the antifungal activity of six betaine derivatives against Malassezia restricta, which is the most frequently isolated fungus from the human skin and is implicated in the development of dandruff. We found that, among the six betaine derivatives, lauryl betaine showed the most potent antifungal activity. The mechanism of action of lauryl betaine was studied mainly using another phylogenetically close model fungal organism, Cryptococcus neoformans, because of a lack of available genetic manipulation and functional genomics tools for M. restricta. Our genome-wide reverse genetic screening method using the C. neoformans gene deletion mutant library showed that the mutants with mutations in genes for cell membrane synthesis and integrity, particularly ergosterol synthesis, are highly sensitive to lauryl betaine. Furthermore, transcriptome changes in both C. neoformans and M. restricta cells grown in the presence of lauryl betaine were analyzed and the results indicated that the compound mainly affected cell membrane synthesis, particularly ergosterol synthesis. Overall, our data demonstrated that lauryl betaine influences ergosterol synthesis in C. neoformans and that the compound exerts a similar mechanism of action on M. restricta.

Dermatitis facial por Malassezia pachydermatis / Facial dermatitis caused by Malassezia pachydermatis

Se presenta un caso de dermatitis facial por Malassezia pachydermatis en un paciente de 34 años de edad, diagnosticado mediante clínica y estudio micológico. M. pachydermatis es una levadura que forma parte de la microbiota de mamíferos domésticos y animales salvajes, donde frecuentemente puede provocar dermatitis y otitis externa. En humanos, son escasas las infecciones por este agente, describiéndose desde infecciones superficiales hasta fungemias. En Chile se la ha encontrado como agente causal de pitiriasis versicolor y dermatitis seborreica principalmente en pacientes inmunocomprometidos.

We present a clinical case of facial dermatitis due to Malassezia pachydermatis in a patient of 34 years old, diagnosed by clinical and micology study. M. pachydermatis is a zoofilic yeast that is part of the microbiota of domestic mammals and wild animals, frequently causing dermatitis and external otitis. In humans, infections by this agent are very scarce, describing from superficial infections to fungemias. In Chile it has been found as causal agent of pitiriasis versicolor and seborrheic dermatitis mainly in inmunocompromised patients.

Especies del género Malassezia en piel sana de niños y adolecentes con VIH-SIDA / Malassezia species on healthy skin of children and teens with HIV / AIDS

Antecedentes: Las especies del género Malassezia forman parte de la biota cutánea normal humana y pueden ser aisladas en áreas ricas en glándulas sebáceas. Su colonización es alta durante edad prepuberal y puberal debido al aumento de actividad de dichas glándulas. Objetivo: Determinar la colonización por especies del género Malassezia en piel sana de niños y adolescentes con VIH/SIDA. Metodología: Las muestras fueron tomadas mediante el método de la impronta con cinta adhesiva transparente, en cuero cabelludo, pabellón auricular, pecho, espalda, muslo, antebrazo, palma de la mano e inoculadas en el medio con base de goma Spondia dulcis. La identificación de las especies se realizó siguiendo las claves descritas por Guého et al. Se realizó el test de difusión en tween propuesto por Guillot et al, la prueba de la catalasa, y la utilización de triptófano como fuente única de nitrógeno. Resultados: De un total de 80 niños y adolescentes, solo 23(28.75 por ciento) de ellos se les aisló Malassezia. 10 (43.48 por ciento) de sexo masculino y 13 (56.52 por ciento) de sexo femenino. Solo se encontró, Malassezia sympodialis con un predominio del 100 por ciento. Correspondiendo al mayor porcentaje de positividad al grupo etario de 4-7 años (56.52 por ciento). Las localizaciones anatómicas predominantes fueron: pabellón auricular (25.5 por ciento) seguida de pecho (21.3 por ciento) y espalda (19.1 por ciento). Conclusiones: En niños con HIV/SIDA se observa un patrón de colonización por M. sympodialis.

Background: Malassezia species are part of the normal human skin biota and can be isolated from different body areas, mainly those rich in sebaceous glands. Colonization is high during prepuberal and puberal for the increased activity of the sebaceous glands. Aims: Determine the colonization by Malassezia species in healthy skin of children and teenagers with HIV/AIDS. Methods: Samples were taken using imprint method with transparent adhesive tape, were taken from scalp, ear, chest, back, thigh, forearm and palm; were inoculated in Spondias dulcis medium. The species identification was performed according the instructions described by Guého et al, Tween diffusion test proposed by Guillot et al, catalase test, and the use of tryptophan as only source of nitrogen. Results: From a total of 80 children and teenagers, only 23 (28.75 percent) of them were isolated Malassezia. 10 (43.48 percent) were from males and 13 (56.52 percent) from females. Found only Malassezia sympodialis with a prevalence of 100 percent. Corresponding to the higher percentage of positivity the age group 4-7 years (56.52 percent). The predominant anatomical locations were: ear (25.5 percent) followed by chest (21.3 percent) and back (19.1 percent) respectively. Conclusions: In children with HIV / AIDS colonization pattern observed is the present of M. sympodialis.

Aislamiento e identificación fenotípica y genotípica de cepas de Malassezia spp. en pacientes con pitiriasis versicolor / Isolation and identification phenotypic and genotypic strains of Malassezia spp. in patients with pytiriasis versicolor

Antecedentes: Pitiriasis versicolor (PV) es una infección micótica superficial crónica de la piel, debido a la colonización del estrato córneo por Malassezia sp. Tradicionalmente M. furfur era considerada el agente causal de PV, hoy en día se ha demostrado que las especies de Malassezia más comunes cultivadas a partir de de lesiones de PV son M. globosa y M. sympodialis. Objetivos: Evaluar la epidemiología de la dermatomicosis PV, en pacientes de la ciudad de Talca, Chile. Metodología: En este estudio, 19 pacientes diagnosticados con PV fueron evaluados. Se realizó identificación fenotípica e identificación molecular por técnica de PCR-RFLP. Para esto, se diseñaron partidores que amplificaron una zona del 26S ADNr presente en todas las especies de Malassezia. Resultados: De un total de 19 pacientes con PV, 7 correspondieron a sexo masculino (36,8 por ciento) y 12 a sexo femenino (63,2 por ciento). Se obtuvieron 18 cepas, a partir de las pruebas fenotípicas fue posible identificar presuntivamente 11 especies de M. globosa (61,1 por ciento) y 7 especies de M. sympodialis (38,9 por ciento). Con los resultados obtenidos en la PCR-RFLP fue posible identificar 11 especies de M. globosa (61,1 por ciento) y 7 especies (38,9 por ciento) de M. sympodialis. Conclusiones: La especie identificada fenotípicamente y molecularmente en mayor proporción fue Malassezia globosa seguida de Malassezia sympodialis. Por lo que hay concordancia entre ambas técnicas de identificación. Este es el primer trabajo de investigación realizado en Talca, Chile, que identificó las especies de Malassezia spp. involucradas en PV, siendo un aporte al estudio de este cuadro clínico.

Background: Pytiriasis versicolor (PV) is a fungal infection of the skin due to the stratum corneum colonization by Malassezia sp. M. furfur traditionally was considered the etiological agent of PV but today it has been shown that M. globosa and M. sympodialis are the most common Malassezia species cultivated from PV lesions. Objective: To evaluate the epidemiological features of PV in patient of the Talca city, Chile. Method: In this study, 19 patients with diagnosis of PV were evaluated. Phenotypic and molecular identified were performed using PCR-RFLP. To do this, primers to amplify 26S ADNr secuence were designed. Result: From a total of 19 patients who presented PV, 7 were male (36.8 percent) and 12 female patients (63.2 percent). Eighteen strains were obtained, from the phenotypic tests, it was possible to presumably identify 11 species of M. globosa (61.1 percent) and 7 species of M. sympodialis (38.9 percent). With PCRRFLP results it was possible to identify 11 species of M. globosa (61.1 percent) and 7 species (38.9 percent) of M. sympodialis. Conclusion: The most commonly isolated species were Malassezia globosa followed by Malassezia sympodialis. So, there is agreement between both techniques of identification. This is the first research work carried out in Talca, Chile, which identified the species of Malassezia spp. Involved in PV, being a contribution to the clinical diagnosis.

In vitro Susceptibility of the Six Malassezia Species to Itraconazole, Fluconazole and Terbinafine / 대한의진균학회지

BACKGROUND: Malasseiza species are dimorphic and lipophilic fungi which are part of normal mycota of the human skin, and also associated with some skin diseases. In many skin diseases such as pityriasis versicolor, Malassezia folliculitis, seborrheic dermatitis, atopic dermatitis and psoriasis, Malassezia yeasts may have a key role. OBJECTIVE: To investigate susceptibility of antifungal agent including itraconazole, fluconazole and terbinafine, we conducted in vitro susceptibility test revealing minimum inhibitory concentration of drugs for each Malassezia strains. METHODS: Malassezia restricta CBS7877, M. globosa CBS 7966, M. slooffiae KCTC 27517, M. sympodialis CBS 7222, M. pachydermatis CBS 1879 and M. furfur CBS 1878 were used in this experiment. The strains were grown in Leeming and Notman medium. MIC was determined using the method suggested by Sugita, et al. with modification. Malassezia cells were grown in each well and incubated for 2 days at 34℃, and MIC was determined by agar dilution method. RESULTS: Most Malasseiza strains of all Malassezia species were most sensitive to itraconazole, with MICs ranging from 0.015 to 0.06 µg/mL. MIC values of fluconazole and terbinafine against Malassezia species were higher and wider range than MIC of itraconazole. CONCLUSION: Itracozanole would be the first choice drug for treatment of Malassezia associated skin diseases. Isolation of pathologic species of Malassezia from various skin diseases in Korea would be fundamental research for the target therapy, and drug susceptibility test would be helpful for proper treatment.

Tinea Versicolor Mimicking Pityriasis Rubra Pilaris caused by Malassezia globosa / 대한의진균학회지

Tinea versicolor (TV) is a common fungal skin disease caused by the Malassezia species. This disease usually presents as hypopigmented- or hyperpigmented coalescing scaly macules, papules, patches or plaques on the trunk and upper arms. Herein, we report a rare clinical manifestation of TV in a 29-year-old man presenting with marked follicular, erythematous, and hyperkeratotic papules on the trunk with erythematous scaly macules and patches on the upper extremities with intermittently spared skin. We initially suspected pityriasis rubra pilaris, however, skin biopsy results and mycological examination revealed TV. Polymerase chain reaction-based sequence analysis revealed Malassezia globosa. The patient was successfully treated with oral itraconazole and topical terbinafine.

Pharmacologic treatment of seborrheic dermatitis

Seborrheic dermatitis is a chronic, recurrent papulosquamous skin disorder characterized by flaking of the skin, erythema, pruritus, and oily skin. It is a common dermatosis, with a prevalence of approximately 1% to 3% of the general population in the United States. The incidence of this skin disease has a bimodal distribution, with peaks noted in newborns and in adults between 30 and 60 years of age. In adults, it predominantly occurs over areas of the body with a high concentration of sebaceous glands. The etiology of this disease is thought to be an inflammatory response of the body to Malassezia yeasts. It is also related to abnormal sebum secretion, as well as a heightened immune response of the host. Based on the characteristic features of this inflammatory skin disease, the mainstays of treatment for seborrheic dermatitis are antifungals, corticosteroids, and immunomodulatory agents. The primary goal of therapy for seborrheic dermatitis is to manage acute symptoms, including pruritus, erythema, and scaling. Maintenance treatment is directed toward preventing the recurrence of acute exacerbations. Patients should be informed that seborrheic dermatitis is a chronic condition, with a tendency to recur despite proper treatment. Clinicians should offer suggestions about lifestyle modifications to avoid triggers and choose proper treatment options that ensure the patient's safety.

In Vitro Anti-Malassezia Activity of Castanea crenata Shell and Oil-Soluble Glycyrrhiza Extracts

BACKGROUND: A new shampoo with anti-Malassezia properties obtained from various plants is required to provide seborrheic dermatitis patients with a wider range of treatment options. OBJECTIVE: The aim of this study was to obtain in vitro susceptibility profiles of Malassezia restricta and M. globosa, the most important pathogenic organisms in the development of seborrheic dermatitis, to the plant extracts used in commercial anti-dandruff shampoos. METHODS: Minimal inhibitory concentrations (MICs) were determined for eight candidate plant extracts and two plant-derived natural products diluted with Leeming and Notman medium to final concentrations of 0.016 to 1 mg/ml. RESULTS: Castanea crenata shell, Camellia sinensis leaf, and oil-soluble Glycyrrhiza extracts presented relatively low MIC values (≤0.5 mg/ml) against both strains. The C. crenata shell and oil-soluble Glycyrrhiza extracts demonstrated especially high anti-Malassezia activity, suggesting their potential use in the treatment of seborrheic dermatitis. The extracts also showed fungistatic activity against other common facultative pathogenic yeasts, Cryptococcus and Candida. CONCLUSION: C. crenata shell and oil-soluble Glycyrrhiza extracts could potentially be used as active ingredients in anti-seborrheic and anti-dandruff shampoo formulations. They could be helpful for repeated treatments and regular prophylaxis of scalp seborrheic dermatitis.