Concurrent genotyping and expression of NLRP3 inflammasome in pityriasis versicolor patient's skin lesions.

The goal of this study is to investigate the impact of the rs35829419 SNP on the serum level of NLRP3, and to assess the relationship between NLRP3 and its SNP and vulnerability to Pityriasis versicolor. Pityriasis versicolor (PV) is one of the most frequent skin conditions linked to skin pigmentation changes. Malassezia plays a key role in the pathogenesis of PV. A case-control study, 50 patients with pityriasis versicolor and 44 healthy controls. Real-time PCR was used to genotype NLRP3 (rs35829419) and ELISA assay of NLRP3 levels in tissue samples. There was a significantly higher median NLPR3 levels in PV patients than controls. A significant predominance of A allele of Q 705 K was in patients than controls. The risk of having the disease in the presence of A allele is nearly 10 times than having C allele. In PV patients, there was a significant relationship between NLPR3 levels and Q 705 K genotypes with higher NLPR3 levels in AA genotype. A potential correlation between PV and the Q705K polymorphism, pointing to evidence of NLRP3 alteration in PV patients. The NLRP3 inflammasome may be an appropriate therapeutic target for Malassezia-associated skin disorders.

Next generation mycological diagnosis: Artificial intelligence-based classifier of the presence of Malassezia yeasts in tape strip samples.

BACKGROUND: Malassezia yeasts are almost universally present on human skin worldwide. While they can cause diseases such as pityriasis versicolor, their implication in skin homeostasis and pathophysiology of other dermatoses is still unclear. Their analysis using native microscopy of skin tape strips is operator dependent and requires skill, training and significant amounts of hands-on time. OBJECTIVES AND METHODS: To standardise and improve the speed and quality of diagnosis of Malassezia in skin tape strip samples, we sought to create an artificial intelligence-based algorithm for this image classification task. Three algorithms, each using different internal architectures, were trained and validated on a manually annotated dataset of 1113 images from 22 samples. RESULTS: The Vision Transformer-based algorithm performed the best with a validation accuracy of 94%, sensitivity of 94.0% and specificity of 93.5%. Visualisations providing insight into the reasoning of the algorithm were presented and discussed. CONCLUSION: Our image classifier achieved very good performance in the diagnosis of the presence of Malassezia yeasts in tape strip samples of human skin and can therefore improve the speed and quality of, and access to this diagnostic test. By expanding data sources and explainability, the algorithm could also provide teaching points for more novice operators in future.

Comparative analysis of the distribution and antifungal susceptibility of yeast species in cat facial hair and human nails.

Zoonotic yeast species have been implicated in disease development in both humans and cats. This study analyzed the yeast mycobiota present in feline facial hair and human nails and explored potential interspecies associations. A total of 118 biological specimens were examined, including 59 feline facial hair and 59 human nail samples. DNA extraction and DNA sequencing were performed to identify the specific yeast species. The most predominant yeast species in humans and cats were selected for antifungal susceptibility testing (itraconazole, ketoconazole, miconazole, and terbinafine). The findings unveiled diverse yeast species in cats and humans. Malassezia pachydermatis (45.8%) and Malassezia furfur (30.5%) were the most common yeast species in cats and humans, respectively. However, no significant correlation was detected between the yeast species identified in cats and their owners residing in the same household (p > 0.05). Miconazole exhibited the highest minimum inhibitory concentrations (MICs) against Malassezia pachydermatis and Malassezia furfur in both cat and human isolates, whereas terbinafine showed the lowest MICs against most Malassezia pachydermatis and Malassezia furfur in both cat and human isolates. Diverse yeast species in cat facial hair and human nails suggest possible cross-contamination among humans, pets, and environments.

Malassezia restricta as an unexpected cause of infectious osteomyelitis diagnosed by metagenomic sequencing: a case report and literature review.

BACKGROUND: Malassezia restricta, a lipophilic and lipodependent yeast belonging to the basidiomycetes group, is an opportunistic fungal pathogen associated with various skin diseases, including seborrheic dermatitis and dandruff. Typically, Malassezia infection in neonates manifests as fungemia or hematogenous dissemination to the bone or lungs. However, vertebral osteomyelitis caused by these fungi is rarely reported owing to non-specific clinical presentations and laboratory/imaging findings. The Pathogen Metagenomics Sequencing (PMseq) technique enables direct high-throughput sequencing of infected specimens, facilitating the rapid and accurate detection of all microorganisms in clinical samples through comprehensive reports. CASE PRESENTATION: A 52-year-old male was admitted to our hospital on July 20, 2022 with a 3-month history of ambulatory difficulties and localized low back pain. Magnetic Resonance Imaging (MRI) examination of the spinal column revealed irregular bone destruction affecting the L2, L3, and L5 vertebral bodies. Additionally, low T1 and high T2 intensity lesions were observed at the intervertebral discs between L3 and L5. The presumptive diagnosis of tuberculous spondylitis was made based on the imaging findings, despite negative results in all mycobacterium tests. However, the patient exhibited no improvement after receiving regular anti-tuberculosis treatment for 3 months. Subsequent MRI revealed an expansive abnormal signal within the vertebral body, leading to progressive bone destruction. The absence of spinal tuberculosis or other infective microorganisms was confirmed through culture from blood and pathological tissue from the L4 vertebral body. Subsequently, PMseq was performed on the specimens, revealing M. restricta as the predominant pathogen with the highest relative abundance value. The pathological examination revealed the presence of fungal mycelium in the L4 vertebral body, with positive findings on periodic Schiff-methenamine and periodic acid-Schiff staining. The anti-tuberculosis treatment was discontinued, and an antifungal combination of fluconazole and voriconazole was administered. All symptoms were resolved after 7 consecutive months of treatment, and the patient was able to ambulate autonomously. Vertebral lesions were reduced on MRI during the 13-month follow-up. CONCLUSIONS: M. restricta is not a commonly recognized pathogen associated with infectious vertebral osteomyelitis. However, PMseq can aid in diagnosis, timely treatment, and decision making for some non-specific infectious diseases.

Prevalence and genetic diversity of azole-resistant Malassezia pachydermatis isolates from canine otitis and dermatitis: A 2-year study.

Despite previous reports on the emergence of Malassezia pachydermatis strains with decreased susceptibility to azoles, there is limited information on the actual prevalence and genetic diversity of azole-resistant isolates of this yeast species. We assessed the prevalence of azole resistance in M. pachydermatis isolates from cases of dog otitis or skin disease attended in a veterinary teaching hospital during a 2-year period and analyzed the ERG11 (encoding a lanosterol 14-α demethylase, the primary target of azoles) and whole genome sequence diversity of a group of isolates that displayed reduced azole susceptibility. Susceptibility testing of 89 M. pachydermatis isolates from 54 clinical episodes (1-6 isolates/episode) revealed low minimum inhibitory concentrations (MICs) to most azoles and other antifungals, but 11 isolates from six different episodes (i.e., 12.4% of isolates and 11.1% of episodes) had decreased susceptibility to multiple azoles (fluconazole, itraconazole, ketoconazole, posaconazole, ravuconazole, and/or voriconazole). ERG11 sequencing of these 11 azole-resistant isolates identified eight DNA sequence profiles, most of which contained amino acid substitutions also found in some azole-susceptible isolates. Analysis of whole genome sequencing (WGS) results revealed that the azole-resistant isolates from the same episode of otitis, or even different episodes affecting the same animal, were more genetically related to each other than to isolates from other dogs. In conclusion, our results confirmed the remarkable ERG11 sequence variability in M. pachydermatis isolates of animal origin observed in previous studies and demonstrated the value of WGS for disentangling the epidemiology of this yeast species.

We analyzed the prevalence and diversity of azole-resistant Malassezia pachydermatis isolates in a veterinary hospital. A low prevalence of multi-azole resistance (c.10% of isolates and cases) was found. Whole genome and ERG11 sequencing of resistant isolates revealed remarkable genetic diversity.

Mycobiome of the external ear canal of healthy cows.

Malassezia yeasts belong to the normal skin microbiota of a wide range of warm-blooded animals. However, their significance in cattle is still poorly understood. In the present study, the mycobiota of the external ear canal of 20 healthy dairy Holstein cows was assessed by cytology, culture, PCR, and next-generation sequencing. The presence of Malassezia was detected in 15 cows by cytology and PCR. The metagenomic analysis revealed that Ascomycota was the predominant phylum but M. pachydermatis the main species. The Malassezia phylotype 131 was detected in low abundance. Nor M. nana nor M. equina were detected in the samples.

The mycobiota of the external ear canal of healthy cows was assessed by cytology, culture, PCR, and NGS. The presence of Malassezia was detected by cytology and PCR. Ascomycota was the main phylum and M. pachydermatis the main species. The Malassezia phylotype 131 was also detected in the samples.

Prevalence and clinical findings of feline otitis externa in Midwest Brazil.

This study was conducted to evaluate the prevalence of otitis externa (OE) in cats using cytology, direct otoscopic examination, and parasitological examination through swabs and curettage, and to compare the accuracy between collection methods for parasitological examination. Direct otoscopic evaluation of the external auditory canal (right and left), swabs for cytological examination of the external auditory canal, and collection of cerumen for parasitological examination through swabs and curettage of 137 cats from a veterinary hospital care were conducted between March 2021 and March 2022. The influences of age, sex, habitat, street access, and the presence of fleas on OE were evaluated. Cytological evidence of OE was observed in 25.5 % of cats and was statistically associated with flea and mite parasitism. Otodectes cynotis was found in 13.9 % of the cats. Cocci and Bacilli were the secondary factors in 34.3 % and 22.9 % of cats with OE, respectively. The Malassezia genus was a secundary factor in 57.1 % of the cats with OE. The frequency of OE was high in cats receiving hospital care. O. cynotis was a frequent primary cause of OE in cats. The curette sampling method is a great option for diagnosing O. cynotis infestation due to its ease of use.

High α-diversity of skin microbiome and mycobiome in Japanese patients with vitiligo.

BACKGROUND: Vitiligo is an acquired pigmentary disorder characterized by depigmented patches on the skin that majorly impact patients' quality of life. Although its etiology involves genetic and environmental factors, the role of microorganisms as environmental factors in vitiligo pathology remains under-researched. OBJECTIVES: Our study explored the presence of characteristic bacterial and fungal flora in vitiligo-affected skin and investigated their potential roles in vitiligo pathogenesis. METHODS: We sequenced bacterial 16S rRNA and the fungal ITS1 region from skin swabs collected at frequently affected sites, namely the forehead and back, of patients with vitiligo. We analyzed bacterial and fungal flora in lesional and non-lesional areas of patients with vitiligo compared with corresponding sites in age- and sex-matched healthy subjects. RESULTS: Our findings revealed elevated α-diversity in both bacterial and fungal flora within vitiligo lesions compared with healthy controls. Notably, bacterial flora exhibited a distinctive composition in patients with vitiligo, and the proportional representation of Enterococcus was inversely correlated with the degree of vitiligo progression. Gammaproteobacteria, Staphylococcus spp., and Corynebacterium spp. were more abundant in vitiligo patients, with notable Staphylococcus spp. prevalence during the stable phase on the forehead. Conversely, the proportion of Malassezia sympodialis was lower and that of Malassezia globosa was higher in the progressive phase on the back of vitiligo patients. CONCLUSION: Our study identified some characteristic bacterial and fungal groups associated with vitiligo activity and prognosis, highlighting the potential roles of microorganisms in pathogenesis and offering insights into personalized disease-management approaches.

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.

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.

Is Malassezia nana the main species in horses' ear canal microbiome?

ABSTRACT The objective of this study was to characterize genotypically Malassezia spp. isolated from the external ear canal of healthy horses. Fifty-five horses, 39 (70.9%) males and 16 (29.1%) females, from different breeds and adults were studied. External ear canals were cleaned and a sterile cotton swab was introduced to collect cerumen. A total of 110 samples were cultured into Dixon medium and were incubated at 32 °C for up to 15 days. Macro- and micromorphology and phenotypic identification were performed. DNA was extracted, strains were submitted to polymerase chain reaction technique, and the products obtained were submitted to Restriction Fragment Length Polymorphism using the restriction enzymes BstCI and HhaI. Strains were sent off to genetic sequencing of the regions 26S rDNA D1/D2 and ITS1-5.8S-ITS2 rDNA. Malassezia spp. were isolated from 33/55 (60%) animals and 52/110 (47%) ear canals. No growth on Sabouraud dextrose agar was observed, confirming the lipid dependence of all strains. Polymerase chain reaction-Restriction fragment length polymorphism permitted the molecular identification of Malassezia nana - 42/52 (81%) and Malassezia slooffiae - 10/52 (19%). Sequencing confirmed RFLP identification. It was surprising that M. nana represented over 80% of the strains and no Malassezia equina was isolated in this study, differing from what was expected.

Isolamento microbiológico do canal auditivo de cães saudáveis e com otite externa na região metropolitana de Recife, Pernambuco / Microbiological isolation from the ear canal of healthy dogs and with otitis externa in the metropolitan region of Recife, Pernambuco

Otite externa (OE) é o termo utilizado para definir a inflamação do conduto auditivo externo; esta doença possui diversas etiologias, ocorre em várias espécies e é particularmente frequente em cães. Os microrganismos da microbiota residente comumente estão envolvidos na etiopatogenia da OE, sendo apontados como agentes perpetuadores da doença. O objetivo deste estudo foi investigar o perfil microbiológico de cães com conduto auditivo saudável e com otite na região metropolitana do Recife. Com o auxílio de suabes estéreis foram coletadas amostras das orelhas direita e esquerda de 41 cães, sendo 11 com OE e 30 sem OE. Foi realizado o isolamento bacteriano e fúngico das amostras cultivadas; observou-se positividade em 80% dos cães com orelhas saudáveis e presença de mais de um microrganismo em 38 amostras (63,3%); já nos cães com OE, a positividade foi 95,3%, com infecção polimicrobiana em 77,3% das amostras. No que se refere aos gêneros bacterianos, o perfil de isolamento microbiológico foi idêntico entre os cães otopatas e sadios. Os microrganismos isolados foram Staphylococcus sp., Micrococcus, Bacillus sp., Streptococcus sp. e Malassezia sp.

Otitis externa (OE) is the term used to describe inflammation of the external ear canal. This disease has many etiologies, occurs in several species and is particularly common in dogs. The resident microbiota microorganisms are commonly involved in the OE etiopathogenesis, being frequently appointed as perpetuator agents. The aim of this study was to investigate the microbiological profile of dogs with healthy ears and of others with otitis in the metropolitan region of Recife, Pernambuco, Brazil. With the aid of sterile swabs, samples of right and left ear of 41 dogs, 11 with and 30 without OE, were collected. Bacterial and fungal isolation was performed with cultured samples; positivity was observed in 80% of animals with healthy ears, with the presence of more than one microrganism in 38 samples (63.3%), whereas in dogs with OE, the positivity was 95.3% with polymicrobial infection in 77.3% samples. With regard to the genus, the microbiological profile was identical between healthy and diseased dogs. The microrganisms isolated were Staphylococcus sp., Micrococcus, Bacillus sp., Streptococcus sp. and Malassezia sp.

Especies del género malassezia aisladas en pacientes con psoriasis y sujetos controles sanos / Species of the genus Malassezia isolated in patients with psoriasis and healthy control subjects

La Psoriasis es una enfermedad crónica de la piel, de etiología y patogenia aún desconocida. Se ha propuesto una posible asociación entre la levadura Malassezia y la exacerbación de lesiones cutáneas en pacientes con psoriasis. OBJETIVO: Determinar frecuencia y distribución de especies de Malassezia en pacientes con psoriasis y en un grupo control sano. MATERIAL Y MÉTODO: Se evaluaron 25 pacientes con psoriasis y 55 sanos como grupo control. Se recolectó muestras de piel de 4 sitios anatómicos y se realizó un examen microscópico directo (EMD) con recuento de levaduras y cultivo en medio de Dixon modificado. Las levaduras aisladas se identificaron según características macro y micromorfológicas y pruebas bioquímicas. RESULTADOS: Un total de 396 muestras de escamas de piel de 4 sitios anatómicos obtenidas de 80 pacientes (55 sanos y 25 con psoriasis). Un 67,5% (54/80) de los pacientes presentaron un EMD positivo y la tasa de recuperación por cultivo fue 58,7% (47/80). De las 396 muestras analizadas, un 28 % (111/396) fueron positivas al EMD y un 25,2% (100/396) al cultivo. Las especies aisladas fueron: M. furfur, M. globosa, M. slooffiae y M. sympodialis. CONCLUSIONES: La presencia de Malassezia en la muestra global fue 77,5 %. El sitio anatómico más afectado fue espalda y pecho y las especies identificadas corresponden a las descritas en la literatura internacional, en sujetos sanos y con psoriasis, pero con diferente frecuencia. Se requerirán estudios adicionales para ayudar a dilucidar el posible rol de Malassezia en la exacerbación de lesiones en los pacientes con psoriasis.

Psoriasis is a chronic skin disease of unknown etiology. A possible association between psoriasis exacerbation and Malassezia species has been proposed. AIM: To determine the frequency and distribution of Malassezia species in psoriasis patients and a healthy control group. MATERIAL AND METHODS: 25 psoriatic patients and 55 healthy controls were studied. In each one of them skin scrapings samples were collected, from 4 anatomical sites. KOH yeast count and culture in modified Dixon agar were done. The isolated yeasts were identified according to macroscopic, microscopic and physiologic features. RESULTS: In 80 patients (55 healthy and 25 psoriatic), a total of 396 skin scrapings samples from 4 different anatomical sites were obtained. A total of 67.5% of the patients presented a positive KOH, and the recovery rate per culture was 58.7%. Out of the 396 analyzed samples, 28% (111/396) resulted positive to microscopic examination and 25,2% (100/396) positive on culture. The isolated species were: M. furfur, M globosa, M. slooffiae y M. sympodialis. CONCLUSIONS: The global frequency of Malassezia in the studied sample was 77.5%. It was more frequently detected on the posterior trunk and chest. We found the same species reported worldwide, in healthy and psoriatic patients, but in different frequency. Further research will be needed to clarify a possible role of this yeast on the exacerbation of skin lesions in psoriatic patients.

Atividade antifúngica do óleo essencial de Origanum vulgare frente a Malassezia pachydermatis / Antifungal activity of Origanum vulgare essential oil against Malassezia pachydermatis

Objetivou-se com este estudo avaliar a atividade antifúngica in vitro do óleo essencial de Origanum vulgare frente a isolados clínicos de Malassezia pachydermatis. As folhas secas de O. vulgare foram adquiridas de distribuidor comercial com certificado de qualidade e origem e encaminhadas para extração do óleo essencial e cromatografia. Para realização do teste in vitro, foi utilizada a técnica de microdiluição em caldo (CLSI M27A3) com modificações para fitofármacos e M. pachydermatis. O óleo essencial de orégano foi testado nas concentrações de 28 a 0,87mg/mL diluído em caldo Sabouraud com 1% de tween 80. Todos os isolados foram testados em duplicata. Na análise cromatográfica do óleo essencial, foram identificados 12 compostos, sendo timol, a-terpineno e 4-terpineol os compostos majoritários. A CIM e a CFM dos 42 isolados de M. pachydermatis variaram de <0,87 a 7mg/mL, com valores de CIM50 e CIM90 de 1,18 e 3,28mg/mL, respectivamente. Com este estudo foi possível concluir que M. pachydermatis é sensível ao óleo essencial de orégano mesmo em concentrações baixas. Dessa maneira, o óleo essencial de orégano apresenta-se como promissor na bioprospecção de novos fármacos para o tratamento das otites e dermatites na clínica de pequenos animais...

The aim of this study was to evaluate the in vitro antifungal activity of essential oil of Origanum vulgare against clinical isolates of Malassezia pachydermatis. The dried leaves of O. vulgare were purchased from a commercial distributor with certified quality and origin and referred for essential oil extraction and chromatography. The technique for in vitro testing was microdilution (CLSI M27A3) with modifications to phytochemicals and M. pachydermatis. The essential oil of O. vulgare was tested at concentrations from 28 to 0.87mg/mL in Sabouraud broth diluted with 1% of tween 80. All isolates were tested in duplicate. In the chromatographic analysis of the essential oil 12 compounds were identified, and thymol, α-terpinene, 4-terpineol were the major compounds. The MIC and the MFC of the 42 isolates of M. pachydermatis ranged from <0.87 to 7mg/mL with MIC50 and MIC90 values of 1.18 and 3.28 mg/mL, respectively. With this study it was concluded that M. pachydermatis is sensible to O. vulgare essential oil even at low concentrations. Thus, the essential oil of O. vulgare is presented as bioprospecting in the promising new drugs for the treatment of otitis and dermatitis in small animal clinic...

Identificación de especies de Malassezia aisladas de piel sana en pobladores de Lima, Perú / Identification of Malassezia species isolated from healthy skin in residents of Lima, Peru

Objetivo: Identificar las especies de Malassezia en zonas seborreicas de piel sana en población limeña. Diseño: Estudio descriptivo transversal. Lugar: Instituto de Medicina Tropical æDaniel Alcides CarriónÆ, Universidad Nacional Mayor de San Marcos, Lima, Perú. Participantes: Pobladores asintomáticos. Intervenciones: Empleando la técnica de Mariat y Adan-Campos, se recolectó muestras de piel de 129 pobladores asintomáticos de diversos distritos de la ciudad de Lima. El aislamiento de Malassezia se realizó en medio Dixon modificado e incubado a 32 grados centígrados por 7 días, la identificación de las colonias por sus características macro y micromorfológicas, y la tipificación mediante el estudio de las propiedades bioquímicas y fisiológicas según la técnica de Guillot y col. Principales medidas de resultados: Especie de Malassezia, sexo, edad y región anatómica. Resultados: Se aisló Malassezia spp en 43,4 por ciento de los pobladores, obteniéndose 49,2 por ciento en varones y 37,5 por ciento en mujeres. De las diferentes regiones corporales, 68 cultivos fueron positivos: cuero cabelludo 31 (45,6 por ciento), espalda 36 (52,9 por ciento) y región frontal 1 (1,5 por ciento). El grupo etario con mayor frecuencia de aislamientos (47,2 por ciento) fue el de 14 a 25 años (adolescentes jóvenes). M. slooffiae fue encontrado en 83,8 por ciento y M. obtusa en 16,2 por ciento de los casos. Conclusiones: Se encontró Malassezia spp. en la piel humana sana. M. slooffiae fue la especie predominante de los casos positivos (83,8 por ciento) seguido de M. obtusa (16,2 por ciento)...

Objective: To identify Malassezia species in healthy skin seborrhea areas in Lima inhabitants. Design: Cross-sectional study. Setting: Daniel Alcides Carrion Tropical Medicine Institute, Universidad Nacional Mayor de San Marcos, Lima, Peru. Participants: Asymptomatic persons. Interventions: Skin samples were collected from 129 asymptomatic residents of several districts of Lima city using Mariat and Adan-CamposÆ technique. Malassezia isolation was performed in modified Dixon medium and incubated at 32 grades centigrades for 7 days. Colonies were identified by macro and micro morphological characteristics and typing was determined by biochemical and physiological properties using GuillotÆs technique. Main outcome measures: Malassezia species, participantsÆ gender, age and anatomical region. Results: Malassezia spp was isolated in 43.4 per cent of the residents, 49.2 per cent in men and 37.5 per cent in women. From various body regions 68 cultures were positive: scalp 31 (45.6 per cent), back 36 (52.9 per cent) and frontal region 1 (1.5 per cent). Isolates most common age group (47.2 per cent) was that of adolescents-young (14-25 year-old). M. slooffiae was found in 83.8 per cent and M. obtusa in 16.2 per cent of cases. Conclusions: Malassezia spp. was present in healthy human skin. M. slooffiae was the predominant species in positive cases (83.8 per cent) followed by M. obtusa (16.2 per cent)...

Susceptibility variation of Malassezia pachydermatis to antifungal agents according to isolate source

Malassezia pachydermatisis associated with dermatomycoses and otomycosis in dogs and cats. This study compared the susceptibility of M. pachydermatis isolates from sick (G1) and healthy (G2) animals to azole and polyene antifungals using the M27-A3 protocol. Isolates from G1 animals were less sensitive to amphotericin B, nystatin, fluconazole, clotrimazole and miconazole.