Neurology Flashcards
Type of seizure most common in adults
Temporal lobe epilepsy
- virtually all are complex partial seizures (+/- secondary generalization)
Hx febrile seizures common
Partial part difficult to tx, 2ndary generalization usually responds to drugs
Psych behavioral disorders often coexist
Drugs that lower seizure threshold
Clomipramjbe Clozapine Loxapine Phenothiazine Bupropion Meperidine Inhaled anesthetics Theophylline at level >25 Cyclosporine Flumazenil Quinolones Beta lactams eg imipenem Dalfampridine
Type of seizure that often requires lifelong anticonvulsant therapy
Juvenile myoclonic
Mixed sz types myoclonic absence and/or GTC
Ppt by stress or sleep deprivation
Most refractory sz disorder
Lennox gestault
- heterogenous group of childhood epileptic encephalopathies
- start before age 4 usually
- result of brain malformations perinatal asphyxia , head injury, CNS infection
Another refractory syndrome
Infantile spasms (west syndrome) Attacks start before 6 months - from cerebral dysgenesis, hypoxic ischemic injury, intrauterine infections, or idiopathic
Causes of single seizures
Withdraw from CNS depressants
Acute illness - meningitis, abscess, encephalitis
Toxicity - uremia , lead, carbon monoxide
Drugs which Lower seizure threshold
Head trauma
Hypoxia
Fever
Metabolic - hyponatremia, hypoglycemia, dehydration
Medical procedures - ECT , brain surgery, organ tx, labor and delivery
Chronic seizure disorder causes
stroke or other vascular Mental retardation Neuro development or brain injury Neoplasms cerebral palsy Genetic predispo Head trauma
Genetically caused sz
Childhood absence,
juvenile myoclonic
Mechanism:
- mutation in ion channel function
- mutations affecting CNS development
- block neuronal apoptosis
- nerve cell metabolism dysreg
Secure prognostic factors
Good prognosis : sz free x 2 or more years, successfully tx after first sz; normalized EEG
Poor prognosis: partial sz or multiple sz types in same pt, hx of status epilepticus, polypharmacy needed, traumatic brain lesion visible
Objective data for seizures
EEG - brain electrical activity- abnormalities either before or during sz may be diagnostic
CT- detect gross hemorrhaging fx or trauma, lesions
MRI - can detect smaller lesions vs CT
Aed most significantly associated with birth defects
Valproate
Phenytoin
Some case reports: Phenobarbital Cbz Felbamate All other aed have limited data - class C
Recommendations for pregnant and aed
Single drug at lowest effective dose
Oral contraceptives - may need high estrogen product due to drug intxns
Monitor aed levels due to pk changes eg altered protein biding
Ultrasound at 16-18 weeks to check for neuronal tube defects
Preconception tx with 0.4mg folic acid daily
Daily vitamin K during las 2-4 weeks of pregnancy for prevention of neonatal cerebral hemorrhaging and give vitamin k to newborn after deliv
Aed that can worsen psych
Ethosuximide
Levitiracetam
Benzos and barbiturates
Topiramate and barbiturates
Newly diagnosed epilepsy tx recommendations:
- standard AED: CBZ , PHT, VPA, Pb
- new AED: LTG, GBP, OXC, TOP
Adults w treatment refractory epilepsy:
GBP, TOP, LTG, OXC, LVT, ZON as add-on
New AED: OXC, TOP, LTG may be used as mono therapy in tx resistant partial epilepsy
LTG in tx refractory GTC sz
Percent of costs from epilepsy that are indirect
85% due to missed work by patients and caretakers of children/elderly pts w epilepsy
Clinical diagnosis of Parkinson’s disease
2 of 3 of following:
Tremor
Rigidity
Bradykinesia
Non motor sx of PD
Psych: depression anxiety dementia hallucinations apathy
Sleep - rls
Autonomic
Speech
Sensory
Other - weight loss seborrheic dermatitis sexual dysfxn GI impaired motility
Hoehn and yahr scale
Parkinson’s dz
Stage I unilateral involvement only and minimal or no functional impairment
Stage II: bilateral involvement without impairment of balance
Stage III: postural imbalance, some reduction in activities, capable I leading independent life, mild-moderate disability
Stage IV: severely disabled must walk with assurance , marked incapacitation
Stage V: restricted to bed or wheelchair unless aided
How much daily carbidopa needed to block peripheral conversion of levodopa
75-200 mg/day
So initial carbidopa/levodopa dose is 25/100mg tid or 10/100mg qid
Titrate q 3 days PRN
If no response to 1000 mg lwop dis reconsider PD dx
Clinical use of anticholinergics in Parkinson’s -
Trihexiphenidyl and benztropine
Best in stage 1 and 2 of disease - for tremor
(With levodopa)
Inhibit muscarinic cholinergic receptors in striatum
Benztropine initial dose: 0.5-1mg qhs up to daily dose of 4-6 mg/day
Trihexyphenidyl 1-2 mg first day increase by 2mg increments q 3-5 days to 6-10 mg/day
Drugs to treat PD related psychosis
Clozapine start at 6.25mg qday and titrate slowly
Quetiapine start at 12.5 mg qday
Risperidone and olanzapine effective but reports of worsening PD