Viral particles in CSF…are they the trigger for MUO. A recent report from the University of Georgia suggests, no.
Predictive Signs for MUO
Meningoencephalitis of unknown origin (MUO) is a non-infectious, inflammatory brain disease common in dogs. The vast majority of dogs diagnosed with meningoencephalitis have MUE, not infectious meningitis. MUO includes granulomatous meningoencephalitis (GME) and the necrotizing encephalitides (NME,NLE) and is the term used to describe antemortem non-infectious, inflammatory CNS diseases in dogs and cats. Providing owners with a prognosis when diagnosed with MUO is extremely challenging. A recent study evaluated several prognostic factors on the early survival in dogs with MUO. (https://www.sciencedirect.com/science/article/abs/pii/S1090023322000995)
Key Points:
98 dogs with MUO were included. 30/98 died within 30 days of the diagnosis.
Adding cytosar to a glucocorticoid protocol did NOT alter the prognosis.
Obtundation at presentation was the ONLY factor statistically associated with poor prognosis. Dogs had a 6.6x higher odds of death in the first 7 days, 2.1x increased risk in the first 30 days when presenting with obtunded mentation.
What does this mean for your patients?
It means that we still have a long way to go when sorting out what MUO means, and how it affects dogs. It means that a dog with a severely elevated WBC on CSF, or with other abnormalities on neurologic examination do not necessarily have a poorer prognosis. If you are seeing a patient with multifocal CNS neuroanatomic lesion localization, be sure to evaluate the pet's level of mentation. Survival may be reduced if obtundation is present. Refer as soon as possible for a neurology consultation and/or work up, depending on client preferences.
References: Lawn RW, Harcourt-Brown TR. Risk factors for early death or euthanasia within 100 days of diagnosis in dogs with meningoencephalitis of unkonwn origin. Vet J 2022. vol. 287.
Short and sweet this week. This article was too good to pass up, so please excuse the short TidBit Tuesday this week.
Safe fast to those of you observing Yom Kippur, Happy Feast of St. Francis of Assisi day and Happy Cinnamon Roll day to the rest of you! (Yes, that is actually a THING on October 4th.