INFLAMMATORY MYOPATHIES

Question 1

what are the inflammatory myopathies?

Answer 1

dermatomyositis
polymyositis
inclusion body myositis

Question 2

name this inflammatory disease?

skin and muscle involvement
heliotrope discoloration of upper eyelids with periorbital edema
muscle weakness
visceral cancers

elevated creatine kinase
high titers of ANA w/ anti-ribonuclear antibodies suggest coexistance of SLE or MCTD
anti-MI-2

capillaries targeted

Answer 2

dermatomyositis

Question 3

symmetric proximal muscle weakness

no cutaneous involvement

CD8 and cytotoxic T cells, macrophages are damaged
increased expression of HLA class I molecules on sarcolemma 

direct injury to myofibers by CD8 T cells, inflammed cells found on endomysium

increased levels of creatine kinase, anti-jo-1 (found in patients with interstitial lung disease)

Answer 3

polymyositis

Question 4

insidious, begins with asymmetric involvement of distal muscles

affects >50 years old

CD8+ cytotoxic T-cells present

morphology

• presence of rimmed vacuoles present in myocytes
• vacuoles rimmed by basophilic granules
• vacuolated fibers contain amyloid deposits

Answer 4

inclusion-body myositis