Psychogenic non-epileptic seizures; Huntingdon's Chorea; Hyperkinetic Disorders Flashcards
Describe what would make you think someone is suffering from a psychogenic nonepileptic seizures (pseudoseizure) instead of an epileptic seizure? [5]
Which factors would suggest true epileptic seizure? [2]
Pseudoseizure:
* pelvic thrusting
* family member with epilepsy
* much more common in females
* crying after seizure
* don’t occur when alone
* gradual onset
True epileptic seizure:
- tongue biting
- raised serum prolactin
- post ictal
- UI
How do you tx pseudoseizures? [1]
Cognitive Behavioural Therapy (CBT)
Describe how you would tell a patient what a non-epileptic seizure is
Unlike epileptic seizures, non-epileptic attacks are not the result of physical abnormalities of the brain
Often they are related to the effects of trauma, emotions or stress, or the result of deeply upsetting experiences, sometimes from the forgotten past.
Sometimes emotional stress can produce physical reactions in the body. For example, everyone has blushed in embarrassment or felt their heart thump in their chest when they were nervous or anxious. More extreme stress can actually cause illness and disability. Non-epileptic attacks, fibromyalgia, chronic fatigue and irritable bowel syndrome are all examples of such disorders
One of the commoner causes of non-epileptic attacks seems to be an automatic response of the brain to traumatic memories or intense emotions that would otherwise come into your awareness and be intolerable. In these circumstances the seizure prevents this from happening and protects you from the intense emotional upset or memories that could otherwise be very distressing.
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Pathophysiology of HD? [3]
- autosomal dominant
- trinucleotide repeat disorder: repeat expansion of CAG
- results in degeneration of cholinergic and GABAergic neurons in the striatum of the basal ganglia
- due to defect in huntingtin gene on chromosome 4
What does anticipation mean with regards to HD? [2]
Huntington’s chorea displays something called genetic anticipation. Anticipation is a feature of trinucleotide repeat disorders, where successive generations have more repeats in the gene, resulting in:
* Earlier age of onset
* Increased severity of disease
Clinical features of HD? [4]
Features typical develop after 35 years of age
* chorea
* personality changes (e.g. irritability, apathy, depression) and intellectual impairment
* dystonia
* saccadic eye movements
ZtF:
* Chorea (involuntary, random, irregular and abnormal body movements)
* Dystonia (abnormal muscle tone, leading to abnormal postures)
* Rigidity (increased resistance to the passive movement of a joint)
* Eye movement disorders
* Dysarthria (speech difficulties)
* Dysphagia (swallowing difficulties)
Describe the investigations used for HD [2]
Genetic testing:
- The primary diagnostic tool for HD is genetic testing, which identifies the CAG trinucleotide repeat expansion in the HTT gene on chromosome 4.
- A positive result with ≥40 repeats confirms a diagnosis of Huntington’s disease. Genetic counselling should be offered before and after testing due to the implications of the results.
Neuroimaging:
- While not diagnostic, neuroimaging can support the clinical findings. MRI or CT scans may show caudate nucleus atrophy, but these changes are more evident in advanced stages.
HD
Neuroimaging:
- While not diagnostic, neuroimaging can support the clinical findings. MRI or CT scans may show [] nucleus atrophy, but these changes are more evident in advanced stages.
Neuroimaging:
- While not diagnostic, neuroimaging can support the clinical findings. MRI or CT scans may show caudate nucleus atrophy, but these changes are more evident in advanced stages.
Describe the management for HD:
- Neurological management [3]
- Pyschiatric management [2]
- Nutrional [2] and dysphagia [3]
Neurological Management:
- Tetrabenazine is the first-line treatment for chorea in HD (works by depleting dopamine)
- Deutetrabenazine and valbenazine are alternatives if tetrabenazine is not tolerated.
- For patients with bradykinesia or rigidity, consider a trial of levodopa.
- Amantadine: May also help reduce chorea and has some mood-stabilizing effects.
- Drugs like olanzapine, risperidone, or quetiapine are sometimes used to manage chorea and psychiatric symptoms if associated
Psychiatric Management
* Selective serotonin reuptake inhibitors (SSRIs) or mirtazapine can be used to manage depression and irritability in HD patients.
* Cognitive behavioural therapy (CBT) should be considered for managing obsessive-compulsive disorder symptoms.
* Mood stabilisers like valproate or lamotrigine can be helpful for mood swings or irritability.
* Antipsychotics: These are also used to treat psychosis, severe agitation, or aggression.
Dysphagia Management
* A speech and language therapist should assess swallowing function regularly to minimise risk of aspiration pneumonia. Dietary modifications may be necessary.
* If oral feeding becomes unsafe despite interventions, percutaneous endoscopic gastrostomy (PEG) feeding should be considered.
TOM TIP: An exam scenario may have you counsel someone about getting a genetic test for Huntington’s.
Describe the key points you would need to discuss [3]
The child of someone with the disease has a 50% chance of inheriting the faulty gene (it is autosomal dominant).
They need to be 18 before they can decide whether to get tested.
Your job is to provide information for the patient to make an informed decision for themselves, not to advise them whether to have a test or not.
The outcome is usually that the patient will think about it further and return if they have further questions.
What are the categories of hyperkinesia? [4]
Describe breifly what they are
Dystonia
- Patterned or repetitive movements and/or sustained abnormal posture
Chorea & Myoclonus
- rapid, not patterned, unpredictable movements
Tics:
- Repetitive, ‘unvoluntary’ but suppressable muscle activity
Tremor:
- Rhythmical involuntary movements
Define dystonia [1]
- Describe the patterns of movements [1]
- Often initated or worsened by what? [1]
Definition: a movement disorder in which involuntary sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures or both
Dystonia is patterned = same muscles or groups of muscles involved in producing dystonic movements or postures and movement tends to happen in a particular way or form
Often initiated or worsened by voluntary action and associated with overflow muscle activation
Describe why dystonias occur [1]
Its pathophysiology involves dysfunction within the basal ganglia, specifically in dopaminergic pathways
- This can result from various causes such as genetic mutations, brain injury or certain drugs.
Meige’s syndrome is made up with which two dystonia manifestations?
Blepharospasm +
oromandibular dystonia
Describe the different possible body distributions of dystonia? [5]
Focal:
- 1 body part affected
Segmental:
- >2 contiguous body parts affected
Multifocal:
>2 non-contiguous body parts affected
Hemidistonia:
- Ipsilateral arm and legs
Generalized: ≥3 body parts are affected, including the trunk and ≥2 other sites; with or without leg involvement
Describe the medical [3] surgical [2] and other treatments [2] for dystonia
Medications:
* Anticholinergics: Drugs like trihexyphenidyl and benztropine help reduce muscle contractions by blocking the neurotransmitter acetylcholine.
* Benzodiazepines: Drugs like diazepam or clonazepam can help relax muscles and reduce spasms.
* Dopaminergic Agents: Levodopa or tetrabenazine may be used in certain forms of dystonia.
Surgical treatments:
- Deep Brain Stimulation (DBS): This is the most common surgical treatment for dystonia. Electrodes are implanted in specific brain areas, like the globus pallidus or subthalamic nucleus, to modulate abnormal brain signals. DBS is often used for generalized dystonia or severe focal dystonia unresponsive to other treatments.
* Selective Peripheral Denervation: Involves cutting nerves to specific muscles to reduce contractions. This is sometimes used for cervical
dystonia.
Other
* Physiotherapy/Occupational tx / exercise
* Botox injections - treat focal dystonia by temporarily paralyzing the overactive muscles. The effects last for 3-4 months, after which the injections may need to be repeated.
Define Tremor [1]
Definition: is a rhythmic back-and-forth or oscillating involuntary movement about a joint axis
Tremor axis
Describe physiological tremor with regards to:
- Frequency
- Amplitude
- Distribution
- Posture
- Exacerbating Factos
- Frequency: between 8 to 12 Hz.
- Amplitude: low amplitude
- Distribution: hands and fingers
-
Posture: observed when maintaining a posture
(e.g., holding the hands outstretched) and is
considered an action tremor. -
Exacerbating Factors: emotional stress, fatigue,
caffeine or stimulants, thyroid dysfunction.
What criteria would support a dx of essential tremor? [4]
- Positive Family History (AD)
- Improvement with Alcohol
-
Tremor in Other Locations: it may also involve the head, voice, or
other parts of the body. -
Absence of Rest Tremor: Unlike Parkinson’s disease, which is
characterized by tremor at rest, ET is primarily an action tremor and
does not typically occur when the limbs are at rest.
What frequency of tremor is essential tremor? [1]
Frequency of 6 to 8 Hz.
How long does essential tremor need to occur for before a dx? [1]
What would the tremor look like? [1]
- Tremor must be present for at least three years to be classified as ET
- Progressive bilateral action tremor in both arms, although theseverity may differ between sides.
What four characteristics would indicate someone is suffering from ET PLUS? [4]
- impaired tandem gait
- questionable dystonic posturing
- memory impairment
- other mild neurologic signs of unknown significance but not enough to make an
additional syndrome classification or diagnosis.
What is the freq. of PD tremor? [1]
Typical frequency of a
Parkinson’s tremor is 4-6 Hz.
Describe the typical tremor in PD [3]
Frequent unilateral Onset
Tremor often decreases or
disappears during intentional
movements or when the affected
limb is actively being used. “Re- emergent”.
Resting Tremor. “Pill-Rolling”
What are the causes of infancy-childhood-adolescence onset chorea? [3]
ADCY5, Ataxia-
telangiectasia,AOA1, AOA2, NBIAs, PNKD
What is the Westphal variant of HD? [1]
rare juvenile-onset cases:
- parkinsonism, dystonia, myoclonus, epilepsy, chorea may be absent
Describe what is meant by myoclonus [1]
sequence of non-rhythmic, brief shock-like jerks due to sudden involuntary contraction or relaxation of one or more muscles.
- Not patterned (as opposed to dystonia).
- Myoclonus can be caused or worsened by action, light touch, sound….
Describe what a tic is [1]
Definition: Tics are sudden, brief, intermittent movements (motor tics) or utterances (phonic tics). Motor tics are repeated, individually recognizable and are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement.
Describe the different classifications of tics [2]
1. Motor
* Simple: eye blinking, facial grimacing, shoulder shrugging, and head jerking.
* Complex: involve sequences of coordinated movements.
* echopraxia (repeating someone else’s movements), palipraxia (repetition of one’s own movements)
2. Phonic
* Simple phonic: grunting, barking, moaning, throat clearing, sniffing, hollering…
* Complex: echolalia (repeating someone else’s words or phrases), palilalia (repeating one’s own
utterances, particularly the last syllable, word, or phrase), coprophenomena (RARE!)→shouting of
obscenities, profanities, or other insults
Describe the characteristics of tics [+]
- Urge/Relief (80% pts): premonitory feelings or sensations, which are relieved by the execution of the
tic. - Suppressibility
- Precipitating factors (attention to the tic, stress or relaxation)
- Decrease with distraction
- Wax and wane nature
- Fluctuate spontaneously
- Motor tics persist during sleep in the majority of patients
Describe what is needed for Tourette syndrome criteria [1]
Tourette syndrome criteria:
* Onset < 18 yo and chronic duration (>12 months).
* Both multiple motor tics and one or more phonic tics must be
present at some time during the illness, although not necessarily concurrently
Describe the tx of tics:
- Behavioural therapy [2]
1. Behavioral Therapy
Habit Reversal Training (HRT): Helps individuals recognize the urge to tic and replace the tic with a more
appropriate, competing response.
Relaxation Techniques: Stress and anxiety can exacerbate tics, so learning relaxation strategies like deep
breathing and progressive muscle relaxation can help manage tics
2. Medications:
* Alpha-2 Adrenergic Agonists: Such as clonidine. These are often used as a first-line medication,
especially in children, because they have fewer side effects. Particularly useful in tics with coexisting
ADHD.
* Antipsychotic Medications: Such as aripiprazole, risperidone, and haloperidol. These can be effective in reducing tics but may have side effects like weight gain and sedation.
* Dopamine Depleters: Such as tetrabenazine. These reduce the amount of dopamine in the brain, which can help control tics.
Describe the basic pathophysiology of dystonia [3]
Loss of motor inhibition:
- at cortical, brainstem and spinal levels
- excessive co-contraction of agonist and antagonist muscles causing unwanted spasm
Abnormalities of sensory input:
- abnormal somatosensory spatial and temporal discrimination
Abnormalities of neural plasticity
- risk of repetitive actions leading to dystonia
