Kona, a 4-year-old castrated American Shorthair cat, presents with right nasal congestion, sneezing, mucopurulent discharge, epistaxis, naris non-patent, and swelling over the nose. What are your top differential diagnoses?

• A. Nasal neoplasia, cryptococcus
• B. Nasal neoplasia
• C. Cryptococcus
• D. Nasal neoplasia, cryptococcus, aspergillosis

Answer: (A)

Nasal disease with obstruction and facial swelling in a cat is most often due to a mass lesion or a fungal infection. In this clinical picture, the top possibilities are nasal neoplasia and cryptococcosis. Nasal neoplasia can produce nasal swelling, epistaxis, sneezing, and mucopurulent discharge as the tumor grows and disrupts the nasal passages. Cryptococcosis is a common fungal infection in cats that also causes nasal inflammation with swelling and discharge and can lead to obstruction. While other fungi like aspergillosis can cause similar signs, it is less frequently the primary consideration in cats compared with cryptococcosis, and therefore is not as high on the list of top differentials here. The combination of facial swelling, nasal discharge, epistaxis, and obstruction best fits nasal neoplasia and cryptococcosis, guiding initial diagnostic steps such as imaging and fungal testing.