MUO

Question 1

MUO vs MUA vs MUE

Answer 1

MUO = meningoencephalitis of unknown origin

MUA/E = meningoencephalitis of unknown aetiology

= the same thing

Question 2

What is meningoencephalomyelitis of unknown origin?

Answer 2

• MUO with spinal cord signs

Question 3

What is MUO?

Answer 3

• an autoimmune inflammatory dz affecting the parenchyma of the brain
• it is usually not limited to the spinal cord and also affects the brain, so is usually considered meningoencephalomyelitis of unknown origin

Question 4

Presentation

Answer 4

• the pathology is usually multifocal therefore usually presents with multifocal lesion localisation
• it is likely to present as a progressive neurological dysfunction which can occur at any age

Question 5

Diagnosis

Answer 5

• lesions can be seen on MRI but MRI is not definitively diagnostic
• CSF may show a mixed pleocytosis, but is also not definitively diagnostic

Question 6

Treatment

Answer 6

• long term course of corticosteroids at immunosuppressive doses in combination with other immunosuppressive agents such as cytosine arabinoside
• lomustine and cyclosporin have also been used

Question 7

Prognosis

Answer 7

• response to therapy is variable
  – 1/3 dead by 3w
  – 1/3 dead by 3m
  – 1/3 alive at 3y
• some dogs may need corticosteroids for very extended periods, or even indefinite
• there can be recurrences at long intervals