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.

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.

Isolation and antimicrobial susceptibility of bacteria from external ear canal of cancer patients at Shafa Cancer Hospital-Ahwaz.

A bacteriological study of external ear canal was performed in 52 hospitalized cancer patients and 42 non hospitalized cancer patients at Shafa hospital, Ahwaz. Study was under taken to find out the normal flora changes in the external ear canals and to observe the prevalence of external otitis among these cancer patients. The control group consisted of 40 non-cancer patients. We observed the following bacteria among hospitalized cancer patients. Staphylococcus Coagulase negative (51.9%), Staphylococcus aureus (15.7%) and Streptococcus pneumoniae (11.9%). Similarly, among non hospitalized cancer patients, Staphylococcus Coagulase negative (45.2%), S. aureus (9.5%) and Streptococcus pneumoniae (4.7%). Incidence of Staphylococcus Coagulase negative and Streptococci pneumoniae is higher in control group than that in cancer patients. We have concluded that cancer patients probably suffer from external otitis more frequently because of enhanced colonization by S. aureus (P < 0.05). The antimicrobial susceptibility of these organisms to various antibiotics was determined by disk diffusion method using Muller Hinton agar. In hospitalized cancer patients Staphylococcus Coagulase negative was 25% and 85% resistant to Vancomycin and Penicillin G and in non hospitalized cancer patients, Staphylococcus Coagulase negative were 45% and 80% resistant to Vancomycin and Penicillin G. S. aureus of both the groups (hospitalized & non hospitalized) were resistant to Penicillin G. Similarly, both the groups were 55% and 50% resistance to Vancomycin.

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.