Encephalopathies, Pt. 3 Flashcards
How do infectious encephalopathies typically progress?
rapidly!
What is corticosteroid-responsive tremor syndrome? What signalment is most commonly affected?
“White Shaker Dog” syndrome with fine whole-body or cerebellovestibular tremors
young adult (< 5 y/o) small breeds, typically Malteses and WHWTs
How do patients with corticosteroid-responsive tremor syndrome appear on diagnostics? How is it treated?
typically not done - MRI normal, CSF normal or mild mononuclear pleocytosis
Prednisone —> weaned slowly off
2 y/o MC Chihuahua presents with acute onset of shaking and balance loss. He appears hot, but it is Fall in NY. What is his most likely diagnosis? How would this be treated?
corticosteroid-responsive tremor syndrome
- Prednisone
- short course of low dose oral Diazepam
- Pu Ji Xiao Du Yin
What is thought to cause granulomatous meningoencephalomyelitis (GME)? What signalment is most commonly affected? How does it typically present?
suspected autoimmune inflammatory CNS disorder
middle-aged, female, small breeds - especially Mini/Toy Poodles
cerebellovestibular dysfunction
What tentative and definitive diagnostics are used for GME?
TENTATIVE - CT/MRI, CSF, matching signalment, clinical signs
DEFINITIVE - characteristic histopathological features of lesions predominantly in the white matter, usually at necropsy
How is GME most commonly treated? What are 4 adjunctive treatments recommended?
Prednisone 1-2 mg/kg PO BID
- Leflunomide - antiinflammatory
- Procarbazine - chemo
- Cytosine arabinoside - chemo
- Cyclosporine - immunosuppressant
What is the prognosis of GME like?
- poor historically, overall median survival of 14 days
- focal GME more favorable than multifocal
- prednisone alone is often ineffective
How is Cyclosporine used to treat GME? What side effects may occur?
lipophilic peptide that blocks inflammatory cytokines - MST 2.5 yrs
- vomiting
- diarrhea
- alopecia
- shedding
How is Procarbazine used to treat GME? What side effects may occur?
oral antineoplastic - MST 14 months
- myelosuppression
- hemorrhagic gastroenteritis
How is Azathioprine used to treat GME? What side effects may occur? How is it unique to other treatments?
purine analogue that inhibits DNA synthesis and miosis - MST 5 yrs
- bone marrow suppression
- GI signs
- hepatotoxicity
lag time to clinical effect
How is Cytosine arabinoside used to treat GME? What side effect is of concern?
nucleoside analog that is able to cross the BBB - SQ and IV CRI administration most common
myelosuppression
(MST > 1 yr)
How is Leflunomide used to treat GME?
pyrimidine analogue - safe in dogs, efficacy questionable
What are the 2 forms of necrotizing encephalitis (NE) of small breeds?
- PUG/MALTESE - forebrain dysfunction
- YORKSHIRE - forebrain and brainstem dysfunction
- many breeds affected
What imaging is used to diagnose NE of small breeds?
- CT - hypodense lesions
- T1-weighted MRI - usually not contrast-enhancing
What treatment is recommeded for NE of small breeds? How does it compare to GME?
Prednisone + antineoplastics and immunosuppressants
treatment efficacy decreased —> prognosis is poor
What drug has seen some success in treating NE of small breeds?
Mycophenolate mofetil (MMF) - immunosuppressant
What are some causes of infectious encephalitides?
- VIRAL: distemper in dogs, coronavirus in cats
- FUNGAL: crypto in NY
- Rickettsial
- Protozoal
What treatment is recommended for bacterial meningoencephalitis?
broad-spectrum antibiotics
- surgery may be requires
- patients tend to decompensate while DVMs ponder if it is bacterial
What is a common cause of fungal meningoencephalitis? How do patients typically present?
Cryptococcus —> bird poop
linger for months, then spiral quickly
What treatment is recommended for fungal meningoencephalitis? What concurrent treatment is recommended temporarily?
Fluconazole - kills fungus, but can cause intense inflammatory response
Prednisone