Computed Tomographic Evidence for United Airway Disease in Cats: Concurrent Middle Ear, Upper and Lower Airway Disease.

United airway disease (UAD) expresses an association between inflammatory upper and lower airway disease in humans but has not been reported in clinically affected feline patients. The purpose of this retrospective case series study is to determine the prevalence of CT changes consistent with feline lower airway disease (FLAD; feline asthma/chronic bronchitis) in cats with inflammatory upper airway disease including otitis media. Included were 549 cats with clinical complaints of inflammatory upper airway disease and/or otitis media and CT examinations of the head, neck, and thorax. CT examinations were reviewed for changes consistent with inflammatory upper airway disease (rhinitis, nasopharyngitis, otitis media) and FLAD. Odds ratios for FLAD were calculated for cats with rhinitis, nasopharyngitis, or otitis media and cats with a combination of rhinitis and otitis media. Rhinitis was diagnosed in 348 cats, nasopharyngitis in 253 cats, otitis media in 287 cats, and FLAD in 338 cats. The odds ratio for the concurrent presence of FLAD in cats with rhinitis, nasopharyngitis, or otitis media were 1.62, 1.46, and 1.46, respectively. The odds ratio for FLAD for cats with a combination of rhinitis and otitis media was 2.27. Otitis media was found to be an independent risk factor for FLAD. CT evidence of FLAD is common in cats with inflammatory upper airway disease, and especially in cats with a combination of rhinitis and otitis media. These findings strongly suggest the presence of United Airway Disease in cats.