Otitis media with effusion in two Boston terrier dogs

Abstract

Otitis media (OM) in dogs can occur as a primary condition instead of as an extension of an otitis externa (OE), characterized by the presence of fluid in the middle ear (ME) referred to as OM with effusion (OME). OME has been reported in a brachycephalic breed (boxer), and the same condition is described as primary secretory OM in Cavalier King Charles Spaniels. These dogs can be asymptomatic or present with pain, facial nerve paralysis and reduced hearing. This report describes two cases of OME with associated neurologic signs in Boston terriers with no previous history of OE, normal external ear canals and tympanic membranes. Neurologic evaluation revealed right head tilt along with vestibular ataxia and frequent walking tight circles to the right in case 1, and a dull mentation with a right-sided head tilt and torticollis, vestibular tetra-ataxia, ambulatory tetraparesis and circling to the right in case 2. MRI imaging of the brain was performed. Results showed bilateral OM with right-sided otitis interna and equivocal associated otogenic meningitis in case 1 and right-sided OM in case 2. Myringotomy was performed, and both dogs' ME sampled for cytology that only revealed inflammatory cells; and bacterial cultures which revealed a light growth of Pseudomonas aeruginosa in case 1. ME were flushed with sterile saline. Oral glucocorticoids and antibiotics based on the susceptibility results, and a compound antibiotic and glucocorticoid ear solution were prescribed to case 1. Neurologic improvement was observed a few days after the appointment, but a mild right-sided head tilt remained evident. Owner of case two elected humane euthanasia due to patient respiratory difficulties upon anaesthetic recovery and other concurrent healthy concerns. Current findings reinforce that brachycephalic dogs may be prone to develop OME, and advanced imaging tests are key to the diagnosis.

Keywords: Boston terrier; advanced imaging; brachycephalic; middle ear effusion; otitis media with effusion; vestibular dysfunction.