Muscle Diseases

Question 1

Polymyositis

Answer 1

• autoimmune
• attacks blood vessels
• type of inflammatory myositis

Question 2

Inclusion body myositis

Answer 2

• elderly (>60 yrs)
• chronic onset
• weakness: quads, wrist/finger flexors, neck flexors, dysphagia
• associated with CTD (thyroid) but rarely malignancy
• unresponsive to immunomodulation
• characteristic RINGED VACUOLES

Question 3

Myotonic dystrophy

Answer 3

• autosomal dominant
• weakness: cranial, DISTAL LIMB, ventilatory
• systemic features (cardiac, cataracts, balding)

Question 4

Duchenne’s/Becker’s muscular dystrophy

Answer 4

• x linked mutation of dystrophin gene
• symptoms start age 2-3
• short heel cords, hypertrophy of calves

Question 5

Duchenne’s/Becker’s muscular dystrophy

Answer 5

• x linked mutation of dystrophin gene
• symptoms start age 2-3
• weakness: limb girdle, short heel cords, hypertrophy of calves
• women less severe phenotype
• cardiomyopathy, ventilatory muscle weakness, intellectual impairment

Question 6

Fascioscapulohumeral dystrophy

Answer 6

• autosomal dominant
• recognition 1st decade to adulthood
• weakness: face, scapular fixators, biceps/triceps, foot dorsiflexors