AWABS - Myopathies Flashcards
Classification of myopathies
Primary
Secondary
Primary myopathies
Muscular (muscular dystrophy)
Congenital
Metabolic
Acquired myopathies
Metabolic and endocrine
Dermato- and poly- myositis
Drug induced
Infectious
?Polymyalgia ?Fibromyalgia
Metabolic myopathies
Glycogen storage
Lipid storage
Muscular dystrophy features
Involves dystrophin
Inherited
Progressive
Muscular dystrophy synptoms
Inability to regenerate
Proximal weakness
Respiratory involvement eventually
Myotonia
Types of muscular dystrophy
Dystrophia myotonica
Becker’s
Thomsen’s
Duschenne’s muscular / myotonic dystrophy
Congenital myopathy features
Rare
Genetic defects lead to protein defects
Non progressive
Reduced contractile ability
Metabolic myopathy features
Hereditary enzyme defects
Errors in metabolism of ATP
Examples of glycogen storage diseases
Pompe’s disease
McArdle’s disease
Enzyme affected in Pompe’s disease
Acid maltase
Enzyme affected in McArdle disease
Myophosphorylase
Examples of lipid storage diseases
Carnitine palmitoyltransferase deficiency
Myopathic carnitine deficiency
Examples of acquired metabolic and endocrine myopathies
Thyroid disease
Parathyroid disease
Pituitary disease eg Addison’s
Corticosteroids eg Cushing’s
Diabetes
Acquired infectious causes of myopathy
Trichinosis
Toxoplasmosis
HIV
Coxsackie
Lyme disease
Influenza