Muscle And Nerve Disease Flashcards
(38 cards)
What are the common presentations of muscle disorders?
Weakness of skeletal muscle Short of breath (weakness of respiratory muscle) Poor swallowing (causing aspiration) Cardiomyopathy , arrhythmias Cramp Pain Stiffness Myoglobinuria
What are the common presentations not of babies with muscle disorders?
Poor suck and feeding
Failure to thrive
Floppy
What are their common signs of muscle disease?
Wasting/hypertrophy of muscles
Normal or reduces tone and reflexes
Myotone
Motor weakness
What are the common investigations for assessing muscle disorders?
History and examination Creating kinase (CK) EMG Muscle biopsy Genetic testing
is inflammatory muscle disease an example of a congenital or acquired muscle disease?
acquired
what is the pathology of muscular dystrophies?
cell degeneration - high creatinine kinase (CK)
lose all dystrophin
what is the difference between duchesses MD and Bekers MD?
duchesses muscular dystrophy shows loss of all dystrophin
in beckers there is only partial loss of dystrophin as well as abnormal dystrophin
what does myotonic dystrophy present commonly with?
cataract esp in people under 50yrs
what is the main feature of myotonic dystrophy?
muscles contract and are unable to relax
what channels are affected in familial hypokalaemia periodic paralysis?
Na, Ca, K
what channel is affected in hyperkalaemic periodic paralysis?
Na
what channel is affected in myotonia congenita?
Cl
what muscle diseases are the Na channels affected?
familial hypokalaemia periodic paralysis
hyperkalaemic periodic paralysis
paramyotonic congenita
in what type of muscle disease would you experience symptoms after short bursts of exercise?
disorders of carbohydrate metabolism - glycogenosis
in what type of muscle disease would you experience symptoms after a long endurance exercise?
disorders of lipid (fatty acid) metabolism
in what metabolic muscle disease would you find systemic and constant symptoms?
mitochondrial myopathies / cytopathies
name 2 inflammatory muscle diseases.
polymyositis
dernatomyositis
what investigations would you carry out for inflammation muscle disease?
Creatinine kinase (high)
EMG
biopsy
what would the biopsy show if it was positive for inflammatory muscle disease?
polymyositis - T cells and CD8 cells
dermatomyositis - B cells and CD4 cells
what is the treatment for inflammatory muscle diseases?
immunosuppression
what type of muscle diseases are paramyotonic congenital and myotonia congenital and whats the difference between the two?
channelopathies
paramyotonia congenita is due to Na channels
myotonia congenital is due to Cl channels
what is the pathophysiology of myasthenia gravis?
autoimmune disorders in which the body produces an antibody against the ACh receptors so no neurotransmitter is released
results in not being able to contract muscle
what is the clinical presentation of myasthenia gravis?
fatiguable weakness which progresses as the day goes on; in the limbs eyelids = ptosis talking swallowing shortness of breath diplopia muscles of mastication
what investigations are used to diagnose myasthenia gravis?
ACh receptor antibody
anti-MuSK antibody
assess neurophysiology by repetitive stimulation
CT chest - check for thymoma