6 - Inflammatory Muscle Disease Flashcards
Inflammatory muscle diseases include?
Polymyositis
Dermatomyositis
Who get inflammatory muscle diseases?
Females 45-60 yo
What are polymyositis and dermatomyositis?
What causes them?
Inflammatory changes to skeletal muscle
Can be:
- infections agent (i.e. virus)
- non-infectious (i.e. meds, toxins)
- hereditary factors
- autoimmune
MC presenting symptom of polymyositis and dermatomyositis (IMD)?
Weakness (NO pain)
Symptoms of polymyositis and dermatomyositis (IMD)?
Weakness (no pain)
Low endurance
Difficulty w repetitive movements
Onset and muscles affected with polymyositis and dermatomyositis (IMD)?
Gradual onset
Proximal muscle groups symmetrically
- neck
- pelvic
- thigh
- shoulder muscles
Dermatological signs of polymyositis and dermatomyositis (IMD)?
“Heliotrope rash” - eyelids (unlike lupus) “Shawl sign” - V shaped flat erythematous lesions ‘Gottron’s sign” - erythematous, scaly eruption, symmetric - over MCP and IP, or psoriasis like “Mechanic’s hands”
Pulmonary signs with polymyositis and dermatomyositis (IMD)?
Weakness of respiratory muscles Interstitial pneumonia (inflammation) Aspiration pneumonia (muscle weakness)
PE tests for polymyositis and dermatomyositis (IMD)?
“Chair test”
“Get up and Go” test
Labs for polymyositis and dermatomyositis (IMD)?
Proximal muscle biopsy - lymphoid inflammatory infiltrates
CK Aldolase AST/ALT LDH EMG
Anti Jo-1 antibodies
ANA pos
What lab establishes dx of polymyositis and dermatomyositis (IMD)?
EMG
Tx for polymyositis and dermatomyositis (IMD)?
Corticosteroids - prednisone 1-2mg/kg/day (high) x 1 yr Steroid sparing agents - methotrexate - azathioprine (no good) - Myhcophenolate mofetil (DM) - Cyclophsphamide IVIG/rituximab (ILD)
polymyositis and dermatomyositis (IMD) has a very poor prognosis if?
Associated w underlying malignancy
polymyositis and dermatomyositis (IMD) needs what consults?
Rheum
Pulm
Neuro
