A shortened whole brain radiation therapy protocol for meningoencephalitis of unknown origin in dogs

Abstract

IntroductionA variety of treatment options have been described for canine meningoencephalitis of unknown origin (MUO). Few studies focused on radiation therapy as a second line immunomodulating treatment, implicating its effective use. However, a standard radiation therapy protocol is lacking, and further research will help to evaluate the effect of different dose regimens.MethodsTen dogs diagnosed with MUO based on MRI and CSF findings were prospectively enrolled. The dogs were treated with a shortened whole brain radiation therapy protocol (5 × 4 Gy) in combination with prednisolone. Neurologic changes were quantified using an established scoring scheme. Follow-up MRI and CSF examination was scheduled three months after radiation therapy. Overall survival and time to progression were calculated. Histopathology of the brain was performed in case of death.ResultsSeven dogs were diagnosed de novo and three had a history of relapsing MUO. Neurological status improved in all 10 dogs during radiation therapy, with 4/10 returning to normal shortly after radiation therapy. Three dogs died within the first three months after radiation therapy. At follow-up MRI lesions completely resolved in two dogs, partially resolved in five dogs, and progressed in one dog. After follow-up MRI, dogs were further treated with prednisolone monotherapy (two dogs) and additional immunosuppressant drugs (five dogs). Overall, four dogs showed disease progression, with a mean time to progression of 691 days (95%CI: 396–987) and mean overall survival for all dogs was 723 days (95%CI: 436–1011) (both medians not reached). Histopathology confirmed MUO in three dogs but was suggestive for oligodendroglioma in one dog. Radiation induced side effects were not seen.ConclusionShortened whole-brain radiation therapy could be an additional treatment option for MUO in conjunction to prednisolone, specifically for cases that require rapid relief of symptoms and with relapsing history.

Off-Label Use of Crisdesalazine (GedaCure) in Meningoencephalitis in Two Dogs

“…Although the exact etiology and pathophysiology of MUO are currently unknown, the suspected triggers of the condition include environmental factors and antigens [ 1 , 2 ]. Considering the generally positive response to immunosuppressive treatment, it is thought that the conditions comprising MUO are immune-mediated [ 16 , 17 ]. In this study, we used crisdesalazine as an add-on to ongoing immunosuppressive treatment, with an expectation of anti-inflammatory and anti-oxidative benefits, or an immunosuppressant-sparing effect on this inflammatory brain disease.…”

Usefulness of neurological assessment scales in prognosis of meningoencephalitis of unknown origin in Yorkshire Terriers

“…A modi ed Glasgow Coma Scale (MGCS) was proposed by Shores for use in veterinary medicine [17], the usefulness of which was subsequently con rmed in a large group of animals [18][19]; however, correlation with the prognosis of dogs with in ammatory diseases has not yet been investigated. The Neuro Disability Scale designed by Smith et al [20] (NDS1), intended as a scoring system for patients with MUO and to provide an objective assessment of their clinical status, allocates arbitrary scores to three categories of clinical de cits and was successfully applied to initial neurological condition assessment and treatment monitoring [21,22]. Attempts at a more complex assessment of the neurological state of patients with MUO in terms of prognosis have recently been undertaken.…”