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.

Microbiome of the External Auditory Canal: Changes After Long-Term Hearing Aid Use.

OBJECTIVE: To investigate the microbial changes of long-term hearing aid use culture independently. STUDY DESIGN: Cross-sectional study. PATIENTS: Fifty long-term hearing aid users and 80 volunteer controls with asymptomatic ears. INTERVENTION: External auditory canal (EAC) sampling with DNA-free swabs. MAIN OUTCOME MEASURES: Microbial communities in the samples were investigated with amplicon sequencing of the 16S rRNA gene. RESULTS: The final analysis contained 48 hearing aid users, 59 controls. Twenty-four samples were excluded because of low sequence count, recent use of antimicrobials and/or corticosteroids, recent cold, or missing health status. The groups showed significant differences in bacterial diversity (beta div., p = 0.011), and hearing aid users showed lower species richness than the control group (alpha div., p < 0.01). The most frequent findings in both groups were Staphylococcus auricularis , Alloiococcus otitis , Cutibacterium acnes , Corynebacterium otitidis , and Staphylococcus unclassified sp. Hearing aid users' samples presented more Corynebacterium tuberculostearicum than the control samples. Common EAC pathogens, such as Staphylococcus aureus or Pseudomonas aeruginosa were rare. CONCLUSION: Long-term hearing aid use lowers bacterial diversity and modulates the EAC microbiome. The changes mostly affect commensals. Lowered diversity may predispose individuals to EAC conditions and needs more research.

Action of mycocins produced by Wickerhamomyces anomalus on Malassezia pachydermatis isolated from the ear canal of dogs.

This study aims to examine the effectiveness of mycocins produced by Wickerhamomyces anomalus in inhibiting Malassezia pachydermatis, a yeast commonly found in the ear canal of dogs. M. pachydermatis has a zoophilic origin and can be found in mammals, and frequently in dogs, where it mainly colonizes the ear canal region and the skin, leading to lesions that are difficult to treat. The antimicrobial mechanism was evaluated using dilutions of supernatant with enzymatic activity, which may include ß-glucanases, glycoproteins known to act on microorganism cell walls. However, it is important to note that this supernatant may contain other compounds as well. ß-glucanases in the mycocins supernatant were found at a concentration of 0.8 U/mg. The susceptibility of M. pachydermatis isolates was tested using the microdilution method. The isolates suffered 100% inhibition when tested with the culture supernatant containing mycocins. In the proteinases production test, 44% of the isolates tested were strong proteinases producers. Subsequently all these isolates suffered inhibition of their activity when tested in research medium containing mycocins supernatant at a subinhibitory concentration of ß-glucanases. This shows that mycocins can inhibit the production of proteinases, a virulence factor of M. pachydermatis. The viability test showed the antifungal action of mycocins in inhibiting the viability of M. pachydermatis cells after a period of 8  hours of contact. These results support the antimicrobial potential of mycocins and their promise as a therapeutic option.

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.

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.

Microbiologia do meato médio em indivíduos sadios / Microbiology of middle meatus in healthy individuals

Introdução: A microbiologia nasossinusal de indivíduos sadios é pouco documentada. Seu conhecimento permite a determinação dos agentes colonizantes nasossinusais e a monitoração dos padrões de resistência bacteriana. Objetivos: Determinar a microbiologia do meato médio em indivíduos sadios e compará-la com a de pacientes com rinossinusite crônica. Método: Foram incluídos 61 indivíduos sadios. As amostras foram coletadas sob visão endoscópica e submetidas a exame de Gram com contagem leucocitária e cultura para aeróbios, anaeróbios e fungos. 114 pacientes com rinossinusite crônica constituíram o grupo controle. Resultados: Nos indivíduos sadios foram isolados 58 microorganismos, sendo os mais prevalentes Staphylococcus coagulase-negativos, Staphylococcus e Corynebacterium. Fungos foram cultivados em 10%.Todas as amostras apresentaram leucócitos raros ou ausentes. Identificou-se resistência à penicilina em 75% dos Staphylococcus aureus e 69% dos Staphylococcus coagulase-negativos. Quanto à oxacilina, 100% dos Staphylococcus aureus e 92% dos Staphylococcus coagulase-negativos foram sensíveis. No grupo controle foram cultivados 158 microorganismos. Os mais freqüentes foram Staphylococcus aureus e coagulase-negativos. Os Gram-negativos representaram 26% dos aeróbios. Entre as amostras com cultura positiva, 73% apresentavam alguns ou numerosos leucócitos. Conclusão: Ausência ou raridade de leucócitos, Staphylococcus coagulase-negativos e Corynebacterium foram mais freqüentes em sadios, e Streptococcus pneumoniae, anaeróbios, Staphylococcus coagulase-negativos oxacilino-resistentes e Gram-negativos mais freqüentes no grupo controle.

Introduction: The nasosinusal microbiology of healthy individuals is not much documented. Its knowledge allows to determine the nasosinusal colonizing agents and to monitor the patterns of bacterial resistance. Objective: To evaluate the microbiology of the middle meatus in healthy individuals and to compare it with that of patients with chronic rhinosinusitis. Method: 61 healthy individuals were included. The samples were collected under endoscopic view and Gram stained with leucocytes count and aerobic, anaerobic and fungus cultures. 114 patients with chronic rhinosinusitis formed the control group. Results: In healthy individuals 58 microorganisms were isolated. The most frequent ones were coagulase-negative Staphylococcus, Staphylococcus and Corynebacterium. Fungi were cultivated in 10%. There were rare or no white blood cells in all samples. There was penicillin resistance in 75% of the Staphylococcus aureus and 69% of the coagulase-negative Staphylococcus. As for oxacillin, 100% of Staphylococcus aureus and 92% of coagulase-negative Staphylococcus were sensitive. In the control group 158 microorganisms were cultivated. The most common ones were Staphylococcus aureus and coagulase-negative Staphylococcus. Gram-negatives represented 26% of the aerobics. 73% of the samples with positive cultures presented a few or many white blood cells. Conclusion: Rare or no white blood cell, coagulase-negative Staphylococcus and Corynebacterium were more frequent in healthy individuals and Streptococcus pneumoniae, anaerobics and oxacillin resistant coagulase-negative Staphylococcus and Gram-negative were more frequent in the control group.

Sensibilidad in vitro a los distintos antifúngicos tópicos disponibles en otomicosis externa / In vitro sensitivity to the different typical antifungoids available in external otomycosis

La otitis externa es motivo de consulta frecuente. Las otomicosis son una fracción pequeña dentro de este grupo que, en ocasiones, suele ser de diagnóstico y manejo más complejo. Muchas veces se presenta en forma recurrente. Los objetivos son conocer el perfil de los agentes causales, lograr un método para estudio de sensibilidad de los hongos a los antimicóticos tópicos, y obtener las bases para guías clínicas. Presentamos un estudio prospectivo en 23 pacientes con un cuadro compatible con otomicosis, obteniendo muestras del conducto auditivo externo, observándolas al fresco y cultivándolas. Estudiamos susceptibilidad a los distintos antimicóticos mediante difusión en discos de Agar, midiendo el halo de inhibición a las distintas cepas. Del total de muestras, 16 (70 por ciento) fueron positivas. La especie más frecuente fue Aspergillus niger (81 por ciento). El antifúngico que logró mejores resultados en susceptibilidad fue timerosal. Otros, como ácido bórico y nistatina, no presentaron halo de inhibición para ninguna de las cepas. La observación al fresco es un método útil, barato y rápido, con buena correlación clínica con el cultivo. La técnica utilizada no permite hablar de sensibilidad propiamente tal. Sin embargo, permite una valoración más objetiva de la respuesta de los hongos antimicóticos. Probablemente sea recomendable usar agentes con mejor halo de inhibición, tales como timerosal y terbinafina.

Microbiota indígena do meato acústico externo de gatos hígidos / Normal microflora of the ear canal in healthy cats

Cinqüenta felinos hígidos, adultos - vinte e seis machos e vinte e quatro fêmeas - sem definiçäo racial, com distintas idades, reunidos em dois grupos (GRUPO 1 - animais domiciliados e GRUPO 2 - animais querenciados) de vinte e cinco animais cada. Após anamnese e prévia sedaçäo, os gatos foram submetidos a exame físico e à otoscopia, comprovando-se a ausência de lesöes meatais e timpânicas, com cureta de Buck e zaragatoas estéreis, foi colhido material meatal, que foi entäo submetido a exames bacteriológico e micológico. No Grupo 1, foi evidenciado presença de Otodectes cynotis (4 porcento das amostras), em 72 porcento dos casos de bolores e leveduras (Cladosporium sp 66,6 porcento, Malassezia sp 40 porcento, Penicillium sp 33 porcento, Aspergillus sp 33,3 porcento, Rhodotorula sp 20,0 porcento, Mycelia sp 13,3 porcento e Alternaria sp, Aureobasidium sp, Rysopus sp, Trichosporon sp, todos com 6,6 porcento) e, finalmente, em 64 porcento da amostragem, bactérias dos gêneros Staphylococcus spp (81,2 porcento), Pseudomonas sp (12,5 porcento), Klebsiella sp (12,5 porcento), Acinetobacter sp, Bacilos difteróides, Enterobacter sp, Lactobacillus spp (todos com 6,2 porcento). No grupo 2, o Otodectes sp foi identificado em 36 porcento das amostras, em 96 porcento daquelas isolaram-se fungos dos gêneros: Malassezia sp - 54,1 porcento, Aspergillus e Penicillium sp, ambos com 33,3 porcento, Microsporum sp - 29,1 porcento, Cladosporium sp - 16,6 porcento, Trichoderma sp - 12,5 porcento, Alternaria e Phoma sp, ambos com 8,3 porcento e Epicoccum sp, Neurospora sp, Mycelia sp, Rhodotorula sp, todos com 4,1 porcento e, por fim, em 20 das 25 amostras (80 porcento) isolaram-se pelo menos uma cepa bacteriana (Staphylococcus spp 75 porcento, Klebsiella sp 20,8 porcento, Bacilos difteróides 12,5 porcento, Pseudomonas sp, 8,3 porcento) e Acinetobacter sp, Enterobacter sp e Escherichia sp, todos com 4,1 porcento cada um em cultivo monoespecífico ou em associaçäo.

Leishmaniasis cutánea del pabellón auricular / Cutaneous leishmaniasis of the ear

Presentamos el caso de una mujer de 48 años con una lesión ulcerada de gran tamaño de 2 meses de evolución a nivel del pabellón auricular. Es diagnosticada de leishmaniasis cutánea mediante el estudio histológico y microbiológico de la lesión. El tratamiento intramuscular con antimoniales pentavalentes, Glucantime®, llevó a la resolución progresiva de las lesiones y ha permanecido asintomática durante un año y medio. La afectación del pabellón auricular es una localización poco frecuente de leishmaniasis cutánea, de difícil tratamiento y con tendencia a cronificarse

A 48 year old female with a big ulcerated lesion localized in the ear of two month of evolution, diagnoses of cutaneous leishmaniasis by histhopatologic and microbiologic study. Was reported treatment with pentavalent ammonial intramuscular (Glucantime®) was perform and the lesion was resolved slowly. The patient was asymptomatic during a year and a half Lesions of cutaneous leishmaniasis when are located in the ear tend to be difficult to treat and chronic