Aetiologies

Skeletal Muscle Myopathies

• Genetic: 

  • Muscular Dystrophies 

    • Myotonic Dystrophy

    • Duchenne's Muscular Dystrophy,

    • Becker's Muscular Dystrophy

  • Mitochondrial Diseases, Glycogen Storage Disorders

• Inflammatory: 

  • Myositis

    • Dermato/polymyositis 

    • Inclusion Body Myositis

• Endocrine

  • Hypothyroidism, Hyperthyroidism

  • Cushing's Syndrome, Adrenal Insufficiency

• Drug induced- statin, steroids, alcohol, 

• Electrolyte disorders: 

  • HyperCalcaemia, HypoCalcaemia 

  • HypoKalaemia, HyperKalaemia, 

  • HypoMagnesaemia, HypoPhosphataemia 

• Infectious- Viral myositis, Influenza, Sepsis

• Rhabdomyolysis 

Related Diseases

Cardiomyopathy

• Dilated- degeneration from ischaemia, hypertension, diabetes

• Restrictive- systemic inflammation: amyloidosis, sarcoidosis

• Hypertrophic cardiomyopathy- genetic 

• Takotsubo Cardiomyopathy 

Diseases of Smooth Muscle

Aetiology

• Immune reaction: Asthma, IBD, Raynaud's / Systemic Sclerosis

• Neurological: Achalasia, Detrusor Overactivity, Gastroparesis

• Growths: Uterine Fibroids (Leiomyomas), Leiomyosarcoma

• Degeneration: Hypertension, 

Neuromuscular Junction

• Myasthenia Gravis (MG) 

• Lamberton Eaton Syndrome (LES) 

Written in 2025.