Charles W Bradley1, Fiona F Lee2, Shelley C Rankin1, Lindsay R Kalan3, Joseph Horwinski3, Daniel O Morris2, Elizabeth A Grice3, Christine L Cain2. 1. Departments of Pathobiology, University of Pennsylvania, 3900 Delancey St, Philadelphia, PA, 19104, USA. 2. Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, 3900 Delancey St, Philadelphia, PA, 19104, USA. 3. Dermatology, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA, 19104, USA.
Abstract
BACKGROUND: Canine otitis externa (OE) is a common inflammatory disease that is frequently complicated by secondary bacterial and/or yeast infections. The otic microbial population is more complex than appreciated by cytological methods and aerobic culture alone. HYPOTHESIS/ OBJECTIVES: Differences in bacterial and fungal populations of the external ear canal will correlate with specific cytological and culture-based definitions of bacterial and Malassezia otitis. ANIMALS: Forty client-owned dogs; 30 with OE and 10 with healthy ears. METHODS AND MATERIALS: Prospective study comparing cytological samples, aerobic bacterial cultures and culture-independent sequencing-based analyses of the external ear canal. Subjects with OE included 10 dogs with only cocci [≥25/high power field (HPF)] on cytological evaluation and culture of Staphylococcus spp.; 10 dogs with rods (≥25/HPF) and exclusive culture of Pseudomonas aeruginosa; 10 dogs with only yeast on cytological results morphologically compatible with Malassezia spp. (≥5/HPF). RESULTS: Staphylococcus was the most abundant taxa across all groups. Ears cytologically positive for cocci had decreased diversity, and all types of OE were associated with decreased fungal diversity compared to controls. CONCLUSIONS AND CLINICAL IMPORTANCE: Cytological and culture-based assessment of the ear canal is not predictive of the diverse microbiota of the ear canal in cases of Pseudomonas or Malassezia otitis. Less abundant bacterial taxa in cases of staphylococcal OE are worth scrutiny for future biological therapy.
BACKGROUND: Canine otitis externa (OE) is a common inflammatory disease that is frequently complicated by secondary bacterial and/or yeast infections. The otic microbial population is more complex than appreciated by cytological methods and aerobic culture alone. HYPOTHESIS/ OBJECTIVES: Differences in bacterial and fungal populations of the external ear canal will correlate with specific cytological and culture-based definitions of bacterial and Malassezia otitis. ANIMALS: Forty client-owned dogs; 30 with OE and 10 with healthy ears. METHODS AND MATERIALS: Prospective study comparing cytological samples, aerobic bacterial cultures and culture-independent sequencing-based analyses of the external ear canal. Subjects with OE included 10 dogs with only cocci [≥25/high power field (HPF)] on cytological evaluation and culture of Staphylococcus spp.; 10 dogs with rods (≥25/HPF) and exclusive culture of Pseudomonas aeruginosa; 10 dogs with only yeast on cytological results morphologically compatible with Malassezia spp. (≥5/HPF). RESULTS: Staphylococcus was the most abundant taxa across all groups. Ears cytologically positive for cocci had decreased diversity, and all types of OE were associated with decreased fungal diversity compared to controls. CONCLUSIONS AND CLINICAL IMPORTANCE: Cytological and culture-based assessment of the ear canal is not predictive of the diverse microbiota of the ear canal in cases of Pseudomonas or Malassezia otitis. Less abundant bacterial taxa in cases of staphylococcal OE are worth scrutiny for future biological therapy.
Authors: Leyna Díaz; Gemma Castellá; M Rosa Bragulat; Andreu Paytuví-Gallart; Walter Sanseverino; F Javier Cabañes Journal: Vet Res Commun Date: 2022-06-15 Impact factor: 2.459
Authors: Fabien Moog; Johanna Mivielle; Jessie Brun; Mirabela Oana Dumitrache; Nicolas Amalric; Line-Alice Lecru; Charline Pressanti; Jevgenija Kondratjeva; Daniel Combarros; Oscar Fantini; Marie Christine Cadiergues Journal: Vet Sci Date: 2022-04-13