Background and Aim: Upper respiratory tract disease (URTD) is prevalent in cats, and diagnosis can be challenging. This study aimed to determine the most common causes of cat URTD in Latvia and describe computed tomography (CT) and laboratory diagnostic findings.

Materials and Methods: The present retrospective study included a total of 94 cats who were diagnosed with URTD. All cats underwent CT, and 50 of them had additional diagnostic tests, such as histology and respiratory infection polymerase chain reaction (PCR) testing.

Results: The most common CT finding was rhinosinusitis (55.32%) followed by nasal neoplasia (26.6%) and nasopharyngeal polyp (14.89%), but in three cats, a cause of respiratory symptoms was larynx neoplasia, nasal dermoid cyst, and an oronasal fistula. PCR test showed that the most cause of rhinosinusitis was Mycoplasma felis. Nasopharyngeal polyp as the primary diagnosis was identified in 14 cats from 3 months to 6 years, with an average age of 1.85 ± 1.915 years, and 54% of cats were female. Nasal neoplasia as a primary CT diagnosis was determined in 25 cats at the age of 5–18 years, with an average age of 10.56 ± 3.416 years. Histology diagnosis included four types of neoplasia – squamous cell carcinoma, sarcoma, adenocarcinoma, and aplastic carcinoma.

Conclusion: This study describes the most common CT and laboratory findings in cats with URTD. Included information will be helpful for general veterinary practitioners and researchers and will update their knowledge on feline URTD.

Keywords: computed tomography, feline, nasal neoplasia, Mycoplasma felis, rhinitis.