polymyositis + dermatomyositis Flashcards
what
inflammation of muscles
polymyositis
chronic inflammation of muscles
dermatomyositis
connective tissue disorder where there is chronic inflammation of skin and muscles
CK result
inflammation leads to rise
often over 1000
caused of raised CK
polymyositis + dermatomyositis rhabdomyolysis AKI MI Statins
malignancy
Polymyositis or dermatomyositis can be caused by an underlying malignancy. This makes them paraneoplastic syndromes.
common assoc cancers
lung
breast
ovarian
cancer
presentation
muscle pain, fatigue, weakness
bilaterally, proximal muscles
develops over weaks
mostly affects shoulder + pelvic girdle
how to tell difference between polymyositis and dermatomyositis
P occurs w/o any skin features
D is assoc w skin involvement
Dermatomyositis Skin Features
gottron lesions on knuckles, elbows, knees
photosensitive erythematous rash: back, shoulders, neck
purple rash face
periorbital oesema
s/c calcinosis
autoantibodies
anti-Jo-1 (P)
anit-Mi-2 (D)
ANA (D)
diagnosis is based on
clinical presentation raised CK autoantibodies EMG muscle biopsy
first line treatment
corticosteroids
other medical options when 1st line not work
immunosuppresants e.g. azathiprine
IVIg
biologics e.g. infliximab
