Cryptococcosis is the most common invasive fungal infection (IFI) in cats. It most commonly causes invasive rhinosinusitis which often includes disease of the eyes, CNS, local lymph nodes and skin. It can also cause disseminate to essentially any organ in the body including the lung, abdominal viscera, and skeletal system.

The Cryptococcus Latex Agglutination Antigen test is highly sensitive and specific (>95%) for cryptococcosis in dogs and cats. Sample types include serum and CSF. Antigen titers decrease with successful treatment and increase with disease relapse and can therefore be used to help guide antifungal treatment.