Case of the Month

Signalment:

7 yr old MN Shetland Sheepdog

Weight:

27 pounds

Vitals:

Presenting Complaint:

-Had 3 grand mal seizures over about 7 hour period

Progression:

-Previously healthy except seasonal skin allergies-had surgery 6 yrs ago for neuter, 3 yrs ago for dental and 9 days prior to cluster of seizures
-First seizure started while walking-dog began to “chew in the air” then went into lateral recumbence with paddling, stiffening, drooling-seizure lasted approx. 1 minute-lost control of bowels and bladder
-Second seizure started while lying down-began “chewing in air”, tried to get up but collapsed on side and had seizure as before
-Unaware of surroundings during episodes-takes 5-10 minutes to get back to normal-post-ictally he seems frightened, disoriented, agitated-he paces and pants
-Taken to emergency clinic where third seizure occurred- treated with valium and phenobarb and released the next day- home on ½ grain PB bid
-Has seemed pretty normal since discharge from E-clinic-slightly sedate on PB with increased thirst/appetite

Physical Exam: (9 days after cluster seizures)

Diagnostics: (done on day of cluster seizures)

CBC-NSF
CHEM-mild stress hyperglycemia-otherwise NSF

What would be your list of differentials???

What other diagnostics might you recommend (if any)???

Differentials:

Neoplasia, Idiopathic epilepsy, Infarct, Hemorrhage, Inflammation, Infection, Metabolic, Malformation, Other

Localization:

Seizures come from the forebrain or thalamic region

MRI Result:

Abnormal hyperintensity in the left parietal lobe-most consistent with ischemic infarct (stroke)

Summary:

This dog may have a seizure in the future. There will likely be a scar at the sight of the infarct. Once the brain has a seizure, changes occur that make it more likely they will have additional episodes. This dog should be kept on anti-convulsant medication. If he goes 12 months without a seizure, then the medication can be tapered and finally stopped. More importantly, another seizure could be a manifestation of a scar or another stroke. If a future seizure is associated with him being weak or circling to one side before or after the seizure then another stroke should be considered. An effort should be made to identify underlying causes of infarct. Chronic inflammation (dental disease, chronic active hepatitis, skin disease, immune-mediated disease, PLE, PLN) as well as some endocrine disorders can all upset the balance and lead to thrombosis.

Recommended Testing:

UA with protein quantification +/- Antithrombin III level
Blood pressure
ACTH Stimulation
Thyroid profile
CPK +/- ANA
+/- Thoracic radiographs +/- Abdominal ultrasound

Recommended Therapy:

Aspirin 0.5 mg/kg q 12 hr (but no higher)
Not enough information available on Plavix at this point

Recommended Follow-Up:

If he has another seizure, he should be observed and then examined looking for evidence of asymmetric clinical signs. CBC/Chemistry/Phenobarb level in 3-4 months. Evaluate seizure frequency relative to anticonvulsant effectiveness and side-effects.