polymyositis and dermatomyositis

Question 1

what causes it?

Answer 1

CD8+ macrophages destroy healthy muscle fibres

Question 2

what is dermomyositis?

Answer 2

polymyositis + skin infections

Question 3

how would a patient present?

Answer 3

symmetrical
proximal muscle weakness
difficulty brushing hair
hard to climb stairs
dysphagia
ILD
myocarditis

Question 4

what are the skin manifestations?

Answer 4

V-shapes rash over chest (shawl sign)
gottron’s sign - rash over knuckles
heliotrope rash

Question 5

what antibodies are seen?

Answer 5

ANA
anti-jo-1
anti-spp

Question 6

what will be seen in bloods?

Answer 6

raised inflammatory markers

Question 7

what is the management?

Answer 7

prednisolone + immunosuppressants