Reticulosis of the visual system in a dog

Abstract

A 7‐year‐old male Kerry Blue Terrier had been compensating for a visual deficit for approximately 2 months. Five days before examination, the dog had suddenly lost all vision and the pupils had become widely dilated and unresponsive to light. Ophthalmic examination revealed inflammation of the optic discs. Response to therapy was favourable but temporary. Post mortem findings consisted of granulomatous optic neuritis, meningoencephalitis and chorioretinitis, similar to reticulosis.

Optic neuritis in dogs: 96 cases (1983‐2016)

“…The pathogenesis of these lesions is not known; comparisons have been made to the various diseases known as ‘White Dot Syndrome’ causing chorioretinitis in humans, but these syndromes are not typically associated with optic neuritis. Retinal and choroidal infiltrates have been previously documented with ‘ocular’ GME …”

“…Optic neuritis has been described in association with GME and has been referred to as ‘ocular GME’ . Ocular GME is considered by some to be a manifestation of diffuse or multifocal GME; while concurrent neurologic findings are often described with ocular GME, cases with no other neurologic signs besides blindness have also been reported . Diagnosis of MUE can be challenging.…”

“…Optic neuritis in dogs has been reported with microbial infection, noninfectious and presumed immune‐mediated meningoencephalitis, optic nerve neoplasia, orbital inflammation, trauma, and toxins . An underlying cause is frequently not found in canine optic neuritis …”

“…Conversely, veterinary neurologists refer to optic neuritis as an isolated form of meningoencephalitis, and confirming the diagnosis requires evidence of an inflammatory CSF and/or characteristic diagnostic imaging findings. For example, in the veterinary neurology literature, noninfectious optic neuritis without clinical or diagnostic evidence of concurrent brain lesions has historically been classified as ‘ocular GME’ …”

Perspectives on Meningoencephalomyelitis of Unknown Origin

“…59,62 The third form, ocular GME, clinically manifests with acute signs of visual dysfunction attributable to optic neuritis and is sometimes considered one aspect of disseminated GME. 17,[63][64][65][66][67] Anterior and posterior uveitis also can occur. 68 GME is a distinct pathologic entity in which neuropathologic lesions consist of whorling, perivascular, disseminated, or focal infiltrates of mononuclear cells in the white matter and meninges of the brain and spinal cord (Fig.…”