Definition
Otodectic ascariasis is a contagius, parasitic, otic or cutaneus disease caused by the psorotid mite otodectes cynosis.

Etiology
Otodectic cyanotic is the most commons cause of otitis externa in young cats. Its incidence in dogs is less commons. The mites can also transiently affect humans.

 

Pathophysiology
Otodectic mites feed on epidermal debris and tissue fluid, exposing the host to mite antigen. The ear canal epidermis becomes irritated, producing excessive cerumen and blood.

Clinical presentation
Ear pruritis with black, granular debris in the external ear canal is a symptom. otodectes cynosis may also exist outside of the ear canal and be cause of head and tail pruritis, especially in cats. Papules, crust and excorations may be evident.

Diferential diagnosis
Foreign bodies, bacterial infection, yeast infection, pseudomonas spp. Infection, defects in keratinization, autoimmune diseases, hypersensitivities.

Diagnosis
Diagnosis Otodectic ascariasis may be made by visualization of the mites in the ear canal, mineral oil ear swabs or on skin scraping or acetate tape preparations. However, mites may be difficult to demontrate in ear canal as immunity to the salivary antigens of the mite may develops and the ensuing inflamations may destroy the mites or cause them to leave the ear canal.

Management
Aural and topical parasiticides applied to the ears and entire body, respectly, at varyng intervals for a totals of 30 days is required. Ivermectin (oral weekly, pour on or subcutaneus biweekly) is also effective. All in contract animals must be treated as well