Effect of an anti-inflammatory pomegranate otic treatment on the clinical evolution and microbiota profile of dogs with otitis externa.

Abstract

Canine otitis externa (OE) is a common disease characterised by inflammation of the epithelial tissue of the external ear canal. Secondary infections are frequent, and Malassezia pachydermatis and Staphylococcus pseudintermedius are routinely isolated and treated with antifungal and antibiotic compounds. To analyse the otitis ear microbiome before and after a treatment with prednisolone plus pomegranate or antimicrobial drugs ANIMALS: 15 dogs with nonpurulent OE. A 30 day, double-blinded, multicentre, randomized and controlled parallel-group (1:1) trial was conducted in 15 dogs with nonpurulent OE, following two different topical treatments (prednisolone plus pomegranate versus prednisolone plus antibiotic and antifungal drugs). On days (D)0, D15 and D30, serum and skin otic samples were collected, and clinical examination and microbiome analysis (bacteria and fungi) were performed. Results were compared with validated otitis clinical scores to assess the effectiveness of both treatments. Nine bacterial and four fungal families were detected during the three time-points tested. An increase in fungal diversity (Shannon index) and composition was the most significant change observed after both treatments. At treatment D15 and D30, the reduction in clinical signs was statistically significant in both treatment groups (P≤0.05). Prednisolone plus pomegranate cleanser treatment was able to control the clinical signs of otitis as well as the bacterial and fungal overgrowth. Mild otitis cases associated with microbial overgrowth may be managed with topical antiseptic and anti-inflammatory agents without the need for antibiotic and/or antifungal compounds.