Neurology Flashcards
Clinical Features of Myotonic Dystrophy
Myotonia (and percussion myotonia) Frontalis/Temporalis wasting Bilateral ptosis Distal myopathy Reduced reflexes Dysarthria/nasal speech
Systems involved in Myotonic dystrophy
Ocular: Cataracts
GI: Dysmotility (dysphagia, delayed gastric emptying)
Endocrine: Diabetes, Gynaecomastia, Testicular atrophy
Cardiovascular: Cardiomyopathy, Conduction defects
Respiratory: Sleep apnoea, recurrent LRTIs/aspirations
Other: slow wean from general anaesthetic
Investigations in myotonic dystrophy
EMG: repetetive action potentials after a single stimulus
Annual ECG
Diabetes screening (HbA1c, blood sugars)
Slit lamp (cataracts)
Lung function testing
Management of Myotonic dystrophy
Non-medical:
- MDT approach: physiotherapy, SALT, OT
- Genetic counselling and prenatal diagnosis
- Anaesthetic risk counselling
Medical
- Phenytoin for myotonia
- Diabetes Screening
- Surveillance for:
- -Cataracts
- -Respiratory failure
- -Cardiomyopathy/conduction defects
Genetics of myotonic dystrophy
Mutation in DMPK gene (chromosome 9) - affects ion channels
Autosomal dominant
Trinucleotide repeat pattern (CTG)
Anticipation
Causes of myopathy
Congenital:
- Muscular Dystrophies
- –Axial: Duchenne; Becker; Limb Girdle
- –Craniofascial: Fascioscapulohumeral; Oculopharyngeal
- –Distal myopathies
- Myotonic dystrophy
- Congenital myopathies (nemaline, central core)
- Muscle ion channel disorders
- Metabolic myopathies (glycogen, fatty acid disorders)
- Mitochondrial cytopathies
Acquired
- Inflammatory
- –Polymyositis
- –Dermatomyositis
- –assoc with CTD
- Inclusion body myositis
- Drug induced (statins most common)
- Metabolic
- Endocrine
Drug Induced Myopathy
Statins Fibrates Antimicrobials: rifampicin, sulfonamides, zidovudine ACEi Cochicine Penicillamine Corticosteroids
Inheritance of Myopathies
X-linked
- Duchenne
- Becker
- Emery Dreifuss
AD
- Myotonic dystrophy
- Facioscapulohumeral dystrophy
- Limb-girdle
- Oculopharyngeal
- Periodic paralyses
AR
- Limb girdle
- Metabolic myopathies
- Mitochondrial
Patterns of weakness in muscle disorders
Distal>proximal
- Inclusion body (forearm flexors, quads)
- FSHD
- Myotonic dystrophy
Proximal>distal
- Becker/DMD
- Limb girdle
- Inflammatory/endocrine
- Drug induced
Face with external ocular muscles involved
- Graves myopathy
- Mitochondrial disorder (ptosis, deafness, retinitis pigmentosa)
- MG
Calf pseudohypetrophy
-Becker & Duchenne
Myopathy investigations
Bloods
- CK
- FBC, U&E, LFT, ESR/CRP, bone profile, BM
- TFT, ANA, ANCA, RF
Imaging
- CXR
- Echocardiogram
- Malignancy screening - CT TAP +- PET
Functional
- ECG
- EMG
Features of Dermatomyositis
Acute/subacute symmetrical proximal weakness Dermatological: -Heliotrope rash - Violaceous eyelids -Rash on V of chest/upper back -Gottron's papules -Nailbed capillary
Respiratory
-Lung fibrosis
Cardiac
-Myopericaridtis
Joints/soft tissues
- Arthropathy (large, symmetrical)
- Raynaud’s
Kidneys
- Nephrotic syndrome
- MSGN
What are the types of motor neurone disease?
- Amyotrophic Lateral Sclerosis
- -UMN and LMN - Primary lateral sclerosis
- -Predominantly UMN
- -No wasting - Progressive muscular atrophy
- -Predominantly LMN - Progressive bulbar palsy
- -Bulbar onset
How would you manage a patient with MND?
- MDT approach:
- Neurologist
- MND nurse specialist
- SALT
- Physio
- OT
- Dietician/Nutrition team
- Respiratory (NIV)
- Palliative input - Symptom management
- Spasms (splints, baclofen)
- Respiratory failure (NIV)
- Drooling (anticholinergics)
- Pain (analgesia)
- Poor swallow (enteral feeding, SALT) - Medical
- Riluzole
How would you investigate for MND?
- Predominantly a clinical diagnosis
- El escorial criteria
- 4 body sections
- Definite diagnosis is UMN & LMN in 3 sections - EMG
- MRI brain/spinal cord
- r/o other causes - Bloods
- TSH, HIV, lyme serology
- CK can be raised
Examination findings in MND
- UMN and LMN signs
- Normal sensory/co-ordination signs
- Wasting
- Fasciculations
- Reduced power with variable tone
What is the clinical course of MS?
- Relapsing Remitting
- Becomes secondary progressive - Primary progressive
How do you diagnose MS?
McDonald Criteria
1. ≥2 attacks and ≥2 objective lesions
2. ≥2 attacks and 1 objective lesion With dissemination in space: a) oligoclonal bands b) ≥2 MRI lesions c) Further attack involving different site
- 1 attack and ≥2 objective clinical lesion
With dissemination in time:
a) MRI
b) Second attack - 1 attack and 1 objective lesion
a) DIS shown by MRI/positive CSF
b) DIT shown by MRI, second attack - Insidious neurological progression suggestive of primary progressive MS
a) CSF positive
AND
b) DIS shows by MRI evidence of 9 brain lesions, 2 spinal cord lesions, or mixture of brain/spinal OR positive visual evoked potential with 4-8 MRI lesions
c) DIT shown by MRI or continued progression over a year
Risk factors for MS
- Female x2 risk
- EBV
- Smoking
- Latitude
- Vitamin D deficiency