Idiopathic Inflammatory Muscle Disease -Dr. Lee Flashcards
What can be associated with dermatomyositis?
cancer
**What is the cell involved in polymyositis? what about dermatomyositis?
Cytotoxic CD8+T cells for polymyositis
CD4+T cells for dermatomyositis
What will the histology of polymyositis show? Dermatomyositis?
polymyositis=Inflammatory infiltrate within fascicle.
–> attacking myofiber
dermatomyositis: Perivascular infiltrate around fascicles.
- -> attacking blood vessels
What is the clinical presentation for polymyositis or dermatomyositis?
proximal mm weakness
What mm enzymes will be elevated in myositis? (5)
CPK, aldolase, LDH, AST, ALT
Which muscle enzyme is the best for assessing disease activity of polymyositis?
- creatine phosphokinase (CPK)
- Lactate dehydrogenase (LDH)
- Aldolase
- AST
- ALT
LDH (treatment specific)
CPK is the most sensitive
What is the most skeletal mm specific test?
aldolase
What is the gold standard for diagnosis of myositis?
muscle biopsy
highly specific
What is an uncommon finding in myositis?
Ocular or facial weakness
if these symptoms present, consider alternative diagnosis
**What are some of the important differentials for myositis?
Sarcoidosis: infiltrating idiopathic normally affects the lungs but can affect mm.
Hypothyroidism, hyperthyroidism
alcoholism, drugs
*vast differentials for mm weakness
What are some poor prognosis factors for myositis?
older age at diagnosis
delayed treatment
cardiac and pulmonary involvement
What are some clinical features seen in myositis?
- heliotrope rash
- shawl sign
- v-neck sign
- gottron’s papules (MCP and IP joints)
What is seen in anti-synthetase syndrome?
hyperkeratotic changes in the hands (mechanic’s hands) –> cracking of skin
What can pediatric dermatomyositis present with?
calcinosis
What is the treatment for myositis?
- glucocorticoids –> gradually taper after 4 weeks once response reached
- immunosuppressants
-IVIg
