dermatomyositis Flashcards
age of onset for dermatomyositis?
bimodal (5-14 yo and 45-65)
Pathogenesis of dermatomyositis?
- environmental factors (malignancy, viral infections) trigger an immunde-mediated process in genetically susceptible individuals (various HLA’s and TNF alpha 308A polymorphism in juvenile onset)
What are the genetic susceptibilities of Dermatomyositis?
various HLA’s and TNF alpha 308A polymorphism in juvenile onset
Drugs implicated in drug induced Dermatomyositis:
- hydroxyurea (most common, >50%)
- Statins
- D-penacillamine, cyclophosphamide, BCG vaccine, TNF-alpha inhibitors
Describe the muscle findings in Dermatomyositis.
- slowly progressive symmetric, proximal muscle weakness typically affecting the shoulders, hip girdle, and neck flexors (difficulty walking upstairs, brushing hair, standing from seated position)
Is muscle inovlement in Dermatomyositis painful?
painless (no mylagias)
What muscular organs can be involved in Dermatomyositis?
- esopahageal muscles–> dysphagia
- Cardiac muscle–> EKG abnormalities, CHF, complete heart block
- diaphragm–> rare but life-threatening
What are the classic skin findings of Dermatomyositis?
- gottron’s papules (pathognomonic): lichenoid papules overlying knuckles
- symmetric confluent macular violaceous erythema w/ malar involvement (vs lupus)
- heliotrope sign (due to inflammation of underlying orbicularis oculi muscle, not skin!) of eyelids +- periorbital edema
- holster sign (lateral thighs
- Macular erythema Overlying joints (Gottron’s sign)
- photodistributed poikiloderma
- V-sign or shawl sign of chest/upper back
- mechanics hands
What are the hand findings in Dermatomyositis and what are they a/w?
mechanics hands (rough hyperkeratosis and fissuring of the lateral and palmar side of fingers)
- a/w anti-sythetase syndrome
What nail changes can you see in Dermatomyositis?
- Ragged cuticles
- proximal nailfold w/ dilated capillary loops alternating with areas of vessel dropout
- periungual erythema
What is a symptom of Dermatomyositis that can help differentiate from lupus?
severe pruritis (often on scalp) , lupus not often itchy
what skin finding can you see in dermatomyositis (less common, but more frequently seen in juvenile DM)?
calcinosis cutis
_____ is an uncommon skin finding of dermatomyositis that is a/w anti-CADM-140 antibodies.
Palmar papules (erythematous palmar papules overlying hyperkeraosis/ulcerartion; painful (unlike gottron’s papules)
Vasculitis occurring in adult with dermatomyositis is a/w _________
Malignancy
Juvenile dermatomyositis with severe systemic vasculitis is called ______
Banker variant JDM
Banker variant JDM prognosis and presentation:
- this is juvenile Banker variant JDM with severe vasculitis
- severe course and poor response to tx
- presents with cutaneous ulcerations, muscle infarctions, GI involvement, widespread calcinosis
What pulmonary disease is a/w Dermatomyositis?
interstitial lung disease
rapidly progressive interstitial lung disease in Dermatomyositis is a/w what two antibodies?
- anti-sythetase
- anti-CADM-140
Clinically amyopathic Dermatomyositis presents with _______ and is a/w _____
- classic skin findings but no clinical muscle disease
- a/w ILD and Anti-CADM-140 antibodies
Cancer associated Dermatomyositis is a/w:
- increased age
- rapid disease onset
- skin necrosis
- anti-p155/140 antibodies
Most common cancers a/w Dermatomyositis are:
- ovarian and GI (classic exam answer)
- nasopharyngeal carcinoma in asians
- breast, lung, pancreatic, non-hodgkins
Risk for most cancers a/w Dermatomyositis returns to normal after _____ (how long?)
5 years
Anti-synthetase syndrome presents with:
- acute onset disease
- constitutional symptoms
- raynauds phenomenon
- mechanics hands
- arthritis
- interstitial lung disease
- anti-synthetase antibodies
Is juvenile Dermatomyositis a/w malignancy risk?
NO!
_____ antibodies are a/w calcinosis cutis and contractures in juvenile Dermatomyositis.
- Anti-p140
_____ antibodies are a/w interstitial lung disease in kids with Juvenile Dermatomyositis.
Anti-CADM-140
What are the two variants of juvenile Dermatomyositis?
Classic JDM (Brunsting variant)
- gradual onset of classic skin and muscle disease, calcinosis cutis, corticosteroid responsive
Vasculopathic/ulcerative JDM (Banker variant)
- rapid onset of severe muscle disease, vasculitis w/ systemic symptoms, and poor prognosis
Histopath of Dermatomyositis:
- subtle vacuolar interface
- rare scattered necrotic keratinocytes
- epidermal atrophy
- sparse PV/PA lymphocytic inflam
- massive dermal mucin
Lab testing to order for patient with Dermatomyositis:
- CK/aldolase (increased muscle enzymes)
- EMG
- muscle biopsy= gold standard for dx
- antibodies
First line therapy for dermatomyositis with skin-limited disease?
photoprotection,
topical CS,
TCI,
+- antimalarials
What screening visits/labs should be done for f/u after diagnosing Dermatomyositis?
- re-check muscle enzymes and muscle strength q 2-3 months (if muscle involvement, start systemic steroids)
- physical exam q4-6 months for first 2-3 years to screen for malignancy
first line tx for skin+muscle involvment in Dermatomyositis?
- systemic corticosteroids, MTX, azathioprine
most common cause of death in Dermatomyositis in adults? Kids?
- malignancy in adults (also ischemic heart disease and pulmonary disease)
- kids usually have favorable outcomes with minimal sequelae if treated early and adequate therapy with CS.
Drug induced Dermatomyositis is split into_____
- hydroxyurea induced and non-hydroxyurea induced
Hydroxyurea induced dermatomyositis has a _____ (short/long) latency period and myositis is (present/absent)
long latency (60 months)
- myositis is never seen!!!!
- this is opposed to non-hydroxyurea induced Dermatomyositis which occurs within 2 months and 80% have myositis
drug induced Dermatomyositis resolves after _____
- 1-2 months after discontinuation of med
