Neurology Flashcards
Carbamazepine side effects
SJS (esp HLA-B15:02 Han Chinese)
Agranulocytosis, transient leukopenia, aplastic anaemia
Hepatitis
Tics
Ataxia, dizziness
Headache, drowsiness
Cannot be used in absence or myoclonic epilepsy
Decreases OCP and warfarin
Induces cytochrome P450 (decreases effectiveness others meds)
Clobazam side effects
Apnoea Drowsiness, sedation Ataxia Drooling Paroxysmal hyperactivity
Lamotrigine side effects
Rash 3-5% SJS (inc risk with valproate) 1:100 - need to monitor serum levels Hepatitis Nausea and vomiting Headache Ataxia, dizziness Diplopia
Recommended if AED needed in pregnancy
Dose decreased when use with carbamazepine and phenytoin
Requires very slow titration of dose
Phenytoin side effects
Hirsutism Ataxia Gum hyperplasia Nausea Nystagmus Peripheral neuropathy Glove and stocking red hand syndrome Teratogenic Inhibits absorption folate - megaloblastic anaemia Induces cytochrome P450
Sodium valproate side effects
Vomiting Anorexia Liver toxicity Pancreatitis Retention o weight Oedema Alopecia Teratogenecity, tremors Enzyme inhibition
Hyperammonemia Menstrual irregularities Low WCC and platelets Teratogenic = neural tube defects 1-5% Avoid <2yrs due to mental retardation, fatal hepatotoxicity
Septo-optic dysplasia (de Morsier syndrome) features?
Optic nerve hypoplasia, optic chiasm hypoplasia, absent septum pallucidum, pituitary stalk hypoplasia
Antibiotic causing carbamazepine toxicity?
Erythromycin
Causes of positive Gower’s sign?
DMD, BMD, juvenile dermatomyositis, myotonic dystrophy, Pompe disease (glycogen storage disease type II).
Seizures on EEG precipitated by eye closure indicates what syndrome?
Gastaut syndrome (late onset childhood occipital epilepsy)
- can be mistaken for migraine but has EEG changes similar to Panayiotopoulos syndrome
- Unlike Panayiotopoulos syndrome, seizures occur during the day and EEG changes are activated by eye closure.
Levetiracetam side effects
- Behavioural side effects: agitation, anxiety, aggression or emotional lability are the most common side effect of
- Older children: low mood and the risk of suicidal ideation
- Headache, fatigue
Side effects of topiramate?
- Kidney stones, metabolic acidosis
- Language impairment
- Cognitive, somnolence, word-finding difficulties
- Anorexia and weight loss
- Teratogen
- Rare glaucoma risk
4–6/sec irregular spike and wave pattern, which is enhanced by photic stimulation
Juvenile myoclonic epilepsy
Tx: life-long sodium valproate
Describe the interactions between carbamazepine and lamotrigine
- Lamotrigine may increase the concentration of carbamazepine, increasing the adverse CNS effects of carbamazepine
- Carbamazepine may decrease the concentration of lamotrigine and decrease its efficacy
Describe the mode of inheritance for myotonic dystrophy
Autosomal dominant
CTG triplet repeat expansion leads to anticipation with subsequent generations
What is paramyotonia, and what is it associated with?
- Temperature related myotonia, aggravated by cold weather
- Common scenario = patient out into cold wind, cannot open their eyes, difficulty swimming in cold water
- Alleviated by warm temperatures
- Associated with myotonia congenita
Describe chronic inflammatory demyelinating polyneuropathy (CIDP)
- Acquired disorder of peripheral nerves and nerve roots
- Usually symmetrical glove and stocking, motor > sensory, both proximal and distal muscles
- Globally diminished or absent reflexes
- Cranial nerve and bulbar involvement occur in a minority.
Winging of the scapula is caused by damage to which nerve?
Long thoracic nerve, which supplies the serratus anterior. Originates from C5,6,7 cervical nerve roots.
Visual field deficit caused by surgery for hippocampal sclerosis?
Contralateral homonymous superior quadrantanopia
What are the cardiac complications of DMD?
Early diastolic dysfunction and focal fibrosis proceed to dilated cardiomyopathy, complicated by heart failure and arrhythmia in most patients.
Describe the different hearing tests
- Auditory brainstem response (ABR) testing - neonate
- Kendall-toy test >2.5y - speech discrimination test
- Visual reinforcement audiometry, not ear specific, 6m-2.5y
- Tympanometry - does not assess hearing but checks compliance of tympanic membranes and ear ossicles
What medications are associated with benign intracranial hypertension?
Possible drugs causing BIH are: tetracyclines; sulfonamides; nitrofurantoin; nalidixic acid; cytarabine; cyclosporine; phenytoin; mesalamine; corticosteroid therapy and withdrawal
What are the key features and mechanism of transmission of Friedreich’s ataxia?
- The combination of spinocerebellar degeneration (slurred speech, unsteady gait) with peripheral neuropathy gives the distinctive features of Friedreich’s ataxia: extensor plantar responses with absent lower limb deep tendon reflexes.
- Autosomal recessive inheritance, expansion of GAA repeat
Which cranial nerve has the longest course?
4, trochlear
Describe Mobius syndrome
- Congenital palsy of the abducens (VI) and facial (VII) nerves (close to each other, originate at the pons, infarcts at this level can affect both nerves)
- Results in a lack of facial expression and weakness on eye abduction
- There is occasionally associated syndactyly, supernumerary digits and micrognathia.