B6-015 Myositis Flashcards
what would you expect to see on EMG in a case of inflammatory myopathy?
similar to normal with lower amplitude waves
at three years post diagnosis, patients treated with [….] had better functional outcomes and required less prednisone maintenance therapy
combination therapy
prednisone + azathioprine
because young patients with myositis require long term steroid therapy, […] should be added to their regime
steroid sparing agent (azathioprine)
most appropriate treatment for infectious myositis
IV antibiotics and consider surgical drainage
[….] is often associated with malignancy
dermatomyositis
in women, there is an association of dermatomyositis and […]
ovarian cancer
what would you expect to see on muscle biopsy in a patient with dermatomyositis?
-increased complement activation -> complement deposition on capillaries
-microvasulopathy
-perifasicular atrophy
patients presenting with inflammatory myopathies and severe complications should receive […]
IVIG
features consistent with long term steroid use
moon facies
weight gain
most common neuromuscular disorder in the world
chronic alcohol related neuropathy
2 most common types of painless myopathy
alcohol and steroids
in chronic alcohol related neuropathy, CK levels are typically normal, but
[…] will result in a rapid increase
ingestion of alcohol
normal skeletal muscle
**note: uniform connective tissue and nuclei at edges
distinguishing feature of myocardium
intercalated disc
normal myocardium
**note:1-2 centrally located nuclei, multiple mitochondria, intercalated discs
damage to myofibers directly
myopathic injury
injury that disrupts muscle innervation
neurogenic injury
name some expected skin findings of dermatomyositis
-telangiectasias
-heliotrope rash
-erythema around nail beds, elbows, knees
-tight, shiny, red skin
-maybe pressure point ulcers
upregulation of MHC-1 in myofibers causes an increased expression of ICAM1
dermatomyositis
heliotrope rash and Gottron papules are associated with what autoantibody?
anti-Mi2
interstitial lung disease and nonerosive arthritis are associated with what autoantibody?
anti-Jo1
patients with what autoantibody should not receive methotrexate?
anti-Jo1
paraneoplastic and juvenille myositis cases are associated with what autoantibody?
anti-P155/P140
CD8 positive T cells are prominent in inflammatory infiltrate
polymyositis
on EMG, fewer motor units and increased amplitude indicates
neurogenic lesion
on EMG, normal number of motor units with decreased amplitude indicates
myopathic lesion
most common acquired disorder in patient over 50 years
sporadic inclusion body myositis
weakness of distal muscles
sporadic inclusion body myositis
weakness of wrist, finger flexor muscle, and ankle are most common features
sporadic inclusion body myositis
asymmetrical, non-dominant side affected
sporadic inclusion body myositis
dysphagia is more common with
sporadic inclusion body myositis
vacuoles in muscle
sporadic inclusion body myositis
distribution of weakness for polymyositis
proximal, symmetric
sporadic inclusion body myositis is more common in [.males/females]
males
what is the typical age of onset of sporadic inclusion body myositis?
over 50
what is the typical onset of sporadic inclusion body myositis?
insidious
what is the distribution of weakness associated with sporadic inclusion body myositis?
asymmetric and distal
what is the expected CK levels in sporadic inclusion body myositis?
normal or less than 10x normal
inflammation, rimmed vacuoles, inclusions
sporadic inclusion body myositis
is sporadic inclusion body myositis associated with a good response to therapy?
no
is polymyositis more common in males or females?
females
what is the typical age of onset of polymyositis?
under 50
what is the typical onset of polymyositis?
acute, rapid
what is the expected CK levels in polymyositis?
greater than 10x normal
biopsy shows inflammation and fiber necrosis
polymyositis
does polymyositis generally respond to therapy?
yes
associated with anti-SRP
immune mediated necrotizing myopathy
associated with malignancy, statin treatment, or viral infection
immune mediated necrotizing myopathy
weakness is proximal and severe with CK levels over 3000
immune mediated necrotizing myopathy
scattered necrotic fibers with macrophage infiltration and regenerating fibers
immune mediated necrotizing myopathy
manifestation of sarcoidosis
granulomatous myositis
multinucleated giant cells of the Langhans type with peripherally located nuclei
granulomatous myositis
first line treatment for myositis
glucocorticoid
inhibits dyhyrofolate reductase
methotrexate
advantage of methotrexate over azathioprine
once a week administration
treatment for patients with severe life-threatening weakness such as dysphagia
IVIG
targets CD20 positive B cells
rituximab
promising treatment for recurrent and resistant dematomyositis and polymyositis
rituximab
antimalarial that is 70% effective in controlling skin disease
hydroxychloroquine
perifasicular atrophy
dermatomyositis
CD 4+ T cells
dermatomyositis
CD 8+ T cells
polymyositis
endomysial infiltration of lymphocytes
polymyositis
perimysial infiltration with perifasicular atrophy on biopsy
dermatomyositis
endomysial infiltration with necrotic fibers seen on biopsy
polymyositis