Unlike non-suppurative meningoencephalomyelitis (Polio) in cats, feline meningoencephalitis is most frequently a result of known infections, including FIP, and infections with Toxoplasma spp, Sarcocystis spp and Encephalitozoon spp.
FIV encephalitis has also been reported.
In a recent histological review of tissues from 286 cats with neurological disorders, 32% had inflammatory and/or infectious lesions affecting the central nervous system. Of these, 51% had FIP, 36% had non-specific encephalitis or meningitis, 9% had protozoal tissue cysts (Toxoplasma spp) and 1% had Cryptococcus spp. Other reported causes include FIV, mycosis, immune-mediated and extension of bacterial infection from inner or middle ear.
Diagnosis prior to death can be difficult. CSF analysis is historically the principal test used for diagnosis of intracranial inflammatory conditions. Although increased CSF white cell count and protein concentration can occur secondary to other pathological conditions such as neoplasia, animals with confirmed CNS inflammation rarely have normal CSF, hence it is a sensitive but not specific test. In animals with CNS signs, magnetic resonance imaging (MRI) may be used before CSF collection, adding more information about location of lesions, if any.
- ↑ Negrin, A et al (2007) Results of magnetic resonance imaging in 14 cats with meningoencephalitis. J Feline Med Surg 9:109-116