Hydrocortisone Aceponate for Chronic Otitis: Long-Term Efficacy

Effective management of otitis externa (OE) requires addressing all contributing factors to prevent chronicity and recurrence. Evidence on the long-term efficacy of topical corticosteroids in preventing recurrence and secondary infections remains limited.

This retrospective noncontrolled study evaluated the efficacy of hydrocortisone aceponate (HCA) in resolving non-infectious chronic or recurrent (CR)-OE with or without proliferative changes, and preventing recurrence of acute episodes and secondary infections.

A total of 63 owned dogs (115 ears) with unilateral or bilateral non-infectious CR-OE were included. Most ears were enrolled after resolving infectious otitis, as persistent inflammation or recurrence required further management.

Clinical records from two dermatology referral centres (February 2022-July 2023) were reviewed. Dogs were included if they had recurrent otitis for over a year (≥ 1 year) or chronic otitis (≥ 1 month). Otitis severity was assessed using the Otitis Index Score (OTIS3) scale, and by grading stenosis and hyperplasia severity. Enrolled patients received HCA 0.584 mg/mL at weight-adjusted doses. A reactive phase continued until OTIS3 < 2, followed by a proactive phase with regimens adapted to otitis severity. Concurrent treatments were recorded.

Recurrence was not observed in 79.1% of ears (mean follow-up 202.6 days). Among 24 relapsed ears, 29.17% recurred after treatment discontinuation. Higher recurrence was associated with stopping therapy (p < 0.001) and recent bacterial otitis (p = 0.015). No adverse effects were noted.

The use of HCA appears to be an effective and safe option for reactive and proactive management of non-infectious CRC-OE, reducing recurrences and improving patient and owner quality-of-life.