Small Ani Med- Neuro- Intracranial Neoplasia, Inflammation, & Infection

wilsbach's version from 2016-04-15 18:30


Question Answer
age typically affected?Geriatric
*CSs of intracranial tumors? Clinical signs reflect localization- Some tumors have a specific locale. But CONSIDER *** SEIZURES IN THE OLD ANIMAL (!) (bc 12yo dog proll doesnt have idiopathic epilepsy...derp)
3 medical tx you can use for brain tumors?(1) Anticonvulsants (tumors can cause seizures) (2) Prednisone (anti-inflammatory dose to Decrease peritumoral inflammation and edema) (3) Chemotherapy
2 surgical things you can do to help with brain tumors- and then two other treatment modalities that arent medical managing?SX: Debulking, Removal en bloc. Can also try radiation therapy and gene therapy.
*what is the Most common intracranial neoplasm for dogs & cats?Meningioma
What is signalment like for a DOG with meningioma? CAT?DOG: Dolichocephalics, females. CAT: Males slightly over-represented
What are the things you'd see with MRI to have you know you have a meningioma? (what sign is pretty specific to it too?)**dural tail sign, Extra-axial mass (Extra-axial is a descriptive term to denote lesions that are external to the brain parenchyma), Contrast-enhancing, distinct margins, can see a mass effect
how can sx tx of meningioma differ between cats and dogs? Other txs?Surgical removal (cats) or debulking (dogs), Oftentimes followed up with radiation therapy. You might also consider chemo ( Hydroxyurea, lomustine/CCNU)
prog of meningioma removal? Radiation therapy alone? sx and radiation therapy?in CATS, sx removal can be curative. In dogs, with sx only you get about 1yr. Radiation alone is about 1 yr. sx+radiation= about 1.5yr
what are the 3 Glial Tumors?(1) Oligodendroglioma (2) Astrocytoma (3) Glioblastoma multiforme (GBM) (Anaplastic astrocytoma). NOTE: They are often a mixture but with one predominant cell type
Glial Tumors: which breeds are most affected?Tend to affect brachycephalic dogs (Boxers, Boston terriers, bulldogs)
where is the location of glial tumors? what does this mean for enhancing with contrast on MRI?Intra-axial in location (bc made of brain cells. in brain itself.). May not enhance with IV contrast on MRI
are glial cells infiltrative or are they pretty separate?Infiltrative, Impossible to remove en bloc (debulking sx). However this means Cause less of a mass effect
what are treatment options for a glioma?Surgical debulking, Radiation therapy. Chemo ( Temozolamide - she doesnt recc), Gene therapy
prog of glioma? 6-12 months with definitive therapy (anecdotal experience)....In humans, prognosis remains poor (1-2 years) despite exhaustive research into new therapies
what are 2 kinds of Choroid Plexus Tumors?(1) Choroid plexus papilloma (2) Choroid plexus adenocarcinoma
Choroid plexus papilloma usually occur where? What kinda problems do they cause? How do you tx them?Typically occur in the 4 th ventricle, and can Cause a secondary hydrocephalus. Tx: Not radiation sensitive, so do surgical removal. Consider ventriculoperitoneal shunting for palliation also (prevent hydrocephalus)
which choroid plexus tumor has the worst prog?Choroid plexus adenocarcinoma- May display intracranial metastasis (via CSF paths).
CNS Lymphoma- where does this lymphoma usually start?Can be part of multicentric lymphoma- Less commonly occurs as primary CNS lymphoma
which parts of the CNS are most often affected by a CNS lymphoma?Tends to affect cranial nerves, meninges
how do you tx CNS lymphoma? As for lymphoma elsewhere. Can give intrathecal (injected into spinal canal) chemotherapy (Cytosine arabinoside )
Histiocytic Sarcoma- location? How can this appear on the MRI?Can be located anywhere- MigHT be a forebrain predilection. There are no specific MRI characteristics so this tumor can be the great imitator as other neoplasms or even Encephalitis
how do you tx a CNS histiocytic sarcoma? prog?can try chemo stuff: Lomustine/CCNU. Guarded to poor prog.
which type of tumor are pituitary tumors usually?Usually adenoma.
what are the two types of adenomas the pituitary can get? explain how they act/affect the brian differentlymicroadenoma and macroadenoma. MICRO: This one is associated with pituitary dependent hyperadrenocorticism (True cushings dz). In the CAT you will see acromegaly and insulin-resistant diabetes mellitus. There is No neurologic dysfunction (directly) related to this. MACROADENOMA: These are Large enough to invade/displace surrounding brain tissue, can cause Diencephalic syndrome (forebrain signs)
what is diencephalic syndrome?Basically forebrain signs
how can you treat the two kinds of pituitary tumors? Prog?(micro and macroadenoma) (1) Hypophysectomy (surgical removal of the hypophysis (pituitary gland) ) (2) Radiation therapy (These tumors are radiation sensitive). PROG: Fair prognosis, Median survival time > 1-2 years after radiation therapy
What are CSs associated with Trigeminal Nerve Sheath Tumor?******Unilateral masticatory muscle atrophy (bc Affects the mandibular branch of cranial nerve V). With extension into the brainstem you will see Other cranial nerve dysfunction, Ataxia, paresis, mentation changes, etc.
how do you Dx trigeminal nn sheah tumor? how do you tx?DX: MRI. TX: (1) Radiation therapy (Stereotactic radiosurgery ) (2) Surgery may be attempted (difficult location :( )
Secondary Brain Tumors occur when...Hematogenous metastasis from a distant site
what are the most common secondary (metastasizing) brain tumors? How do they look on imaging?Multifocal, contrast-enhancing lesions, Carcinomas (mammary gland, lung), melanoma, Hemangiosarcoma
what are the most common secondary (local extension) brain tumors?Calvarial tumors (skull dome), Nasal tumors, Squamous cell carcinoma (sinuses, eye).

The autoimmune encephalitises + little white shakers

Question Answer
what are the 3 kinds of ‘Autoimmune’ Encephalitis?Granulomatous meningoencephalitis, Necrotizing meningoencephalitis & leukoencephalitis, Little white shaker dog syndrome
what is the localization of autoimmune encephalitis(s) like? how do you definitively diagnose?Multifocal localization. All require biopsy/necropsy for definitive diagnosis (needless to say, Presumptive diagnoses are commonly made via MRI, CSF findings)
Granulomatous Meningoencephalitis- where does this occur in the CNS? what is the signalment of someone affected by this?Brain and SC can be affected (So if brain + SC, consider GME), Young to middle-aged small breed dogs (might have a female predilection but can affect genders equally).
CSs of GME (Granulomatous Meningoencephalitis) and how they present (onset and stuff)?Acute onset and progressive, Oftentimes hindbrain signs.
if you do a MRI scan of GME, what will you see? Where is it likely to be?May or may not see a lesion, Predominantly occur in the white matter (Mild contrast enhancement with indistinct margins )
what will CSF look like in a GME dog?Mononuclear pleocytosis and increased protein. (Pleocytosis= too many WBCs in the CSF)
what should you know about definitively diagnosing GME?Will need brain biopsy for antemortem definitive diagnosis. Localization of disease limits the ability to biopsy- Forebrain= yes; brainstem= probably not
Necrotizing Meningoencephalitis (NME)--- signalment of who gets this? What are the CSs of this dz?Young to middle-aged dogs, ESP *Pugs (‘pug encephalitis’), and Maltese* (‘Maltese encephalitis’). Clinical signs= forebrain= **SEIZURES
Necrotizing Meningoencephalitis (NME)-- where do you see lesions on the MRI, and how would you describe them? Lesions predominate in the cerebral grey/white matter junction, and are cavitary (kinda makes sense- necrotizing= dead stuff)
what will CSF be like with Necrotizing Meningoencephalitis (NME)? Mononuclear (mostly lymphocytic) pleocytosis and high protein
Necrotizing (Leuko)encephalitis (NLE/NE) signalment?Young to middle-aged Yorkshire terriers (‘yorkie encephalitis’).
CSs of Necrotizing (Leuko)encephalitis (NLE/NE)? Has more of a predilection for the hindbrain, but might also have forebrain signs.
what is NLE/NE like on MRI, what is CSF like?MRI: white matter AND areas of cavitation. Mononuclear pleocytosis and high protein
So GME vs NME vs NLE/NEIn short: GME= fore and hind brain, white matter. small breeds. NME= pug and maltese, forebrain=SEIZURES. Cavitary lesions. NLE= YORKIES, white matter AND cavitary lesions. More hindbrain but can do forebrain.
How can you tx the autoimmune encephalitis's (GME/NME/NLE) and what supportive therapy can you provide?SUPPORT WITH: Anticonvulsants if necessary, Meclizine if vestibular syndrome. Then TX WITH: IMMUNOSUPPRESSION: Mainstay is a slowly tapering immunosuppressive dose of prednisone. Can ad additional chemotheraputics for immunosuppression if needed ((mainstay is steroids tho. tx is LIFELONG)
prog of the autoimmune encephalitis?Poor long-term prognosis... but Good short-term prognosis (And we aim for a good quality of life in the meantime)
Little White Shaker aka? And Signalment?Corticosteroid responsive tremor syndrome. Signalment is Young, small breed dogs (terriers, toys, etc).
CSs of little white shakers? Acute onset of fine tremors
how can you dx little white shaker?CSF shows mild lymphocytic pleocytosis
how do you tx little white shaker? prog? Immunosuppression with prednisone, +/- diazepam or Benadryl to aid in controlling tremors. Prog is good

Infectious Encephalitis

Question Answer
infectious causes of encephalitis in the dog/cat....which is NOT common? Bacterial meningoencephalitis is rare in the dog and cat
what causes rabies? how do animals get it? (pathophys)it is a Lyssavirus, transmitted via bite. Virus makes its way to the CNS via retrograde axoplasmic flow (Has a predilection for the limbic system ). Then there is centrifugal spread back to salivary glands
CSs of Rabies? How does it present/emerge?there will be Paresis/paralysis and ataxia.....2 forms: (1) Dumb: Mentation changes, Profuse salivation and depressed gag reflex. (2) Furious form: aggression. Is uncommon, but keep this on your list for any peracute onset of severe neurologic dysfunction.
Canine Distemper Virus-- what type of virus? how is it transmitted?Morbillivirus (family Paramyxoviridae), xmitted via Respiratory route. Virus carried into the CNS about one week later via infected WBCs and platelets
**what are the 4 Neurological presentations of canine distemper?(1) Younger dogs with grey matter disease (2) Older dogs with predominantly white matter (demyelinating) disease (3) ‘Old dog encephalitis’ (4) Post-vaccinal encephalitis
Distemper neuro presentation: for Younger dogs with grey matter disease, what are the main CSs?Seizures-- can be fatal.
Distemper neuro presentation: for Older dogs with predominantly white matter (demyelinating) disease , what are the main CSs?Mentation and behavior changes, Ataxia, paresis, Cerebellovestibular syndrome
Distemper neuro presentation: for old dog encephalitis , what are the main CSs?Behavior changes, circling, blindness.
Distemper neuro presentation: for Post-vaccinal encephalitis, what are the main CSs?1-2 weeks after vaccination (modified live virus), Bizarre behavior, Ataxia, paresis, recumbency, death
what CS can be a sequale of infection with canine distemper? Myoclonus, which is Rhythmic, repetitive muscle contraction. Lower motor neuron acts like a pacemaker
what is myoclonus, what infection is this associated with?sequalae of canine distemper, it is a Rhythmic, repetitive muscle contraction. Lower motor neuron acts like a pacemaker
3 ways to dx canine distermper?(1) Serum or CSF titers (2) In the serum you will see mononuclear pleocytosis with high protein (Lymphocytes ) (3) Urine PCR
which pleocytosis is common in viral infections?Lymphocytic
how do you tx the canine distemper neuro probs?Anti-inflammatory to immunosuppressive dosages of steroids (controversial).... WHITE matter dz= inflammatory (Virus has already come and gone). GREY= non-inflammatory
what causes FIP? Which type of FIP is related to neuro signs?caused by mutation of a Coronavirus. Dry form can cause CNS signs
DRY FIP causes neuro signs-- what are the CSs/why?Has a predilection for the caudal fossa (Lateral apertures of the 4 th ventricle) so see Cerebellovestibular signs, Forebrain signs--> Obstructive hydrocephalus
dx and tx for dry FIP neuro complications?Dx: MRI, CSF shows mononuclear pleocytosis and very elevated protein. Tx: not very effective :(
Rickettsial Disease--> what neuro problems does this cause? CSs? Cause meningitis (meningoencephalitis) Clinical signs vary and all can have non-neural manifestations. Can see seizures.
3 main rickettsial dzs which can cause neuro signs? (which vectors)(1) Rocky Mountain spotted fever (Rickettsia rickettsii) carried by Dermacentor and Ambylloma ticks. (2) Ehrlichiosis (E. canis) Rhipecephalus tick (3) Salmon poisoning (Neorickettsia helminthoeca)- Pacific NW, Snails and salmon
along with pleocytosis and high protein, what other systemic abnormalities might you see with rickettsial dzs?Petechiae, ecchymoses, thrombocytopenia, elevated globulin, lymphadenomegaly, fever, etc.
what are the two causative agents of Fungal Encephalitis?Cryptococcus neoformans, Blastomyces dermatiditis
CSs of fungal encephalitis?Reflect the location of disease! Extraneural signs: Upper and lower respiratory, Dermatologic, Skeletal
what does fungal encephalitis look like on MRI?Intra-axial, contrast enhancing lesion, Perilesional edema
what will CSF look like with fungal encephalitis?Pyogranulomatous inflammation and high protein, May see the organisms
what antifungal crosses the BBB so you can treat fungal encephalitis?Fluconazole!! (although others might work if the BBB is inflamed).- needs to be LONG TERM treatment. +/- Steroids.
2 things that cause Protozoal Encephalitis?(1) Toxoplasma gondii (2) Neospora caninum
Who can get toxo infection? how do you dx? tx? prog?dogs and cats (but cats DH), May or may not see a granuloma on MRI, CSF analysis: neutrophilic pleocytosis and high protein. Titers might be unreliable. TX: ~clindamycin, trimethoprim sulfa). Prog guarded
Neospora caninum- who is affected by this? is there predilection?Similar clinical picture to toxoplasmosis, onLY DOGS affected tho. Predilection for cerebellum ?
a recommended titer for dogs? Cats?DOGS: Canine distemper virus, Neospora caninum, Toxoplasma gondii, Ehrlichia canis, Rocky Mountain spotted fever. CATS: FeLV, FIV, coronavirus, cyrptococcus, Toxoplasma gondii