Clinicopathologic Features and Magnetic Resonance Imaging Findings in 24 Cats With Histopathologically Confirmed Neurologic Feline Infectious Peritonitis

Crawford, A.H.; Stoll, A.L.; Sanchez-Masian, D.; Shea, A.; Michaels, J.; Fraser, A.R.; Beltran, E.

Each cat underwent postmortem examination. Gross pathologic abnormalities were reported in 14 cats and included ventriculomegaly in 10, flattening of cerebral gyri in 4, meningeal congestion in 4, and white matter edema in 3 cats. Histopathologic abnormalities were detected in all 24 cats. Perivascular neutrophilic and lymphoplasmacytic infiltrates affected the leptomeninges in 16 cats, the choroid plexus in 16, the periventricular space in 13, the spinal cord parenchyma in 8, and the brainstem parenchyma in 5 cats (Figs 4, 5) . Pathologic abnormalities were most commonly detected in the caudal cranial fossa, particularly affecting the caudoventral brainstem. Immunohistochemistry was performed on brain tissue in 10 cats; all showed positive intracellular staining for the feline coronavirus antigen.