Download Chest Pain, SOB, Tachycardia

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42 yoWF with hx of hypothyroidism, depression has a 2 week hx myalgia,
weakness and a CPK of 3000. Adm to PHD CPK of 13379 and AST 225,
ALT 107, LDH 1380 and CRP 2.6 mg/dl. EMG was classic for DM. She was
d/c on Prednisone 80 mg qd but worsened w/ difficulty with stairs, and
combing her hair, proximal weakness and muscle pain. The patient also
complains of subjective fever, fatigue, myalgia, indigestion, and depression.
CPK worsened at home to 11000 and was re-admitted. Rx with steroids,
IVIG and MTX
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21 yoBF with SLE x 2 yrs Rx with Plaquenil and Imuran. She developed
progresive weakness in the arms over 2-3mos and was hospitalized with 2
pillow orthopnea and some RUQ pain and CPK of 12,112 and a Aldoase of
79. Started on prednisone 80 mg/day and Arava 100/wk and discharged
with CPK 2000. She complains of difficulty with stairs, and combing her hair,
and proximal weakness. She denies shortness of breath, dysphagia, and
skin rash. Repeat CPK up to 5000. Steroid increased and pt put on MTX
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56 yoWF wih RA since 2003, On Plaquenil, MTX, failed Enbrel. 2/04, she reports
progressive worsening of weakness to arms and legs. She has difficulty with stairs
getting off the toilet, chairs, upper pharyngeal dysphagia, mainly to pills and water,
food. Also c/o Weight loss of 15 lbs, SOB cough, dry eyes/moutn. found to have m
CPK elevation 458, mild LFTs elevation, with normal aldolase. EMG mixed
myopathic/neuropathic. Bx showed autophagic vacuoloar myopathy
Antimalarial Neuromyopathy
Not dose or duration dependant
 Insidious painless LE/UE weakness
 Clinical myopathy 6.7%; Chemical
myopathy 18.8%
 Bx: classic vacuolar myopathy and EM
curvilinear bodies/complex lysosomes
 Rx: improvement within 2 mos of d/c
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Casado E. Ann Rheum Disease 2005
Polymyositis
Dermatomyositis
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F:M = 2.5:1
Acute onset; all ages (bimodal)
Incidence 2-7/million/year
Weakness (+ myalgia): Proximal > Distal
Skeletal muscle: dysphagia, dysphonia
Sx: Rash, Raynauds, dyspnea
65% elevated CPK, aldolase
50% ANA (+)
90% +EMG; 85% + muscle biopsy
Proposed Criteria for Myositis
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5.
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Symmetric proximal muscle weakness
Elevated Muscle Enzymes (CPK, aldolase,
AST, ALT, LDH)
Myopathic EMG abnormalities
Typical changes on muscle biopsy
Typical rash of dermatomyositis
PM Dx is Definite w/ 4/5 criteria and
Probable w/3/5 criteria
DM Dx Definite w/ rash and 3/4 criteria and
Probable w/ rash and 2/4 criteria
Polymyositis Classification
Bohan & Peter
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4.
Primary idiopathic dermatomyositis
Primary idiopathic polymyositis
Adult PM/DM associated with
neoplasia
Childhood Dermatomyositis (or PM)
 often associated with vasculitis
5.
Myositis associated with collagen
vascular disease
MYOPATHY: HISTORICAL
CONSIDERATIONS
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Age/Sex/Race
Acute vs. Insidious Onset
Distribution: Proximal vs. Distal
Pain?
Drugs/Pre-existing Conditions
Neuropathy
Systemic Features
MYOPATHIES
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Toxic/Drugs
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Infectious
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Muscular dystrophies, hereditary myopathies
Neuropathic/Motor Neuron Disorders
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Coxackie A9, HBV, HIV, Stept., Staph, Clostridial,
Toxoplasma, Trichinella
Congenital neuromuscular disorders
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Etoh, Cocaine, Steroids, Plaquenil, Penicilamine,
Colchicine, AZT, Lovastatin, Clofibrate, Tryptophan
Myasthenia gravis, amyotrophic lateral sclerosis
Endocrine/Metabolic
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Glycogen storage diseases, mitochondrial
Drug-induced myopathy
Amiodarone
Amphetamines
Chloroquine
Cimetadine
Cocaine
Colchicine
Corticosteroids
Cyclosporin
Danazol
Emetine
Ethanol
Fibric-acid Rx
Heroin
Hydralzaine
Hydroxychloroqui
ne
Hydroxyurea
Levodopa
Nicotinic acid
Pancuronium
Penicillamine
Pentazocine
Phenylbutazone
Phenytoin
Procainamide
Rifampin
Statins
Sulfonamides
Tiopronin
Vecruonium
Vincristine
Zidovudine
NONMYOPATHIC
CONSIDERATIONS
Fibromyalgia
 Polymyalgia Rheumatica
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 Caucasians,
> 55 yrs, M=F, ESR > 100,
normal strength, no synovitis
RA
 SLE
 Adult Still's Disease
 Vasculitis
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INCLUSION BODY MYOSITIS
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Bimodal age distribution, maybe
hereditary
Slow onset, progressive weakness
Painless, distal and proximal weakness
Normal or mildly elevated CPK
Poor response to corticosteroids
Dx: light microscopy may be normal or
show CD8+ lymphs. Tubulofilamentous
inclusion bodies on electron microscopy
Role for amyloid?
Presentation of PM/DM
Presentation
Painless proximal weakness
(over 3-6 mos)
Acute/subacute proximal pain
and weakness (wks-2 mos)
Insidious proximal/distal
weakness (< 10 yrs)
Proximal myalgia alone
Dermatomyositis sine myositis
Frequency (%)
55%
30%
10%
5%
<1%
Skeletal Muscle Weakness
Painless; proximal > distal
 Upper Extremity: combing hair, dressing
 Lower: Stairs, toilet, car, falling, gait
 Dysphagia, hoarseness, regurgitation
 Inability to raise head from the pillow
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DERMATOMYOSITIS
5 Skin Features
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Heliotrope Rash: over eyelids
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Seldom seen in adults
Gottrons Papules (60-80%): MCPs,
PIPs, MTPs, knees, elbows
V-Neck Rash (Shawl sign): violaceous
erythema ant. chest w/ telangiectasias
Periungual erythema, digital ulcerations
Calcinosis
Mechanics Hands
Calcinosis
DIAGNOSTIC TESTING
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Physical Examiniation: Motor Strength
(Gowers sign), Neurologic Exam
Acute phase reactants unreliable
Muscle Enzymes
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CPK: elevated >65%; >10% MB fraction is possible
Muscle specific- Aldolase, Troponin, Carb. anhydraseIII
AST > LDH > ALT
Beware of incr. creatinine (ATN) and myoglobinuria
Electromyogram: increased insertional
activity, low amplitude, polyphasics, positive
sharp waves
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Beware of neuropathic changes,
incremental/decremental MU changes
DIAGNOSTIC TESTING
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Muscle Biopsy (an URGENT not elective
procedure)
Call the neuropathologist! 85% Sensitive.
 Biopsy involved muscle (MRI guided)
 Avoid EMG/injection sites or sites of trauma
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Magnetic Resonance Imaging - detects
incr. water signal, fibrous tissue,
infiltration, calcification
Investigational: Tc-99m Scans, PET
Scans
Serologic Tests: ANA (+) 60%, Abs
against t-RNA synthetases
INFLAMMATORY MYOSITIS
Biopsy Findings
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Inflammatory cells
Edema and/or fibrosis
Atrophy/ necrosis/ degeneration
Centralization of nuclei
Variation in muscle fiber size
Rarely, calcification
Anti-synthetase syndrome: ILD, fever, arthritis, Raynauds,
Mechanics hands
PM/DM Complications
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PULMONARY
Intercostal, diagphragm
involvement
Aspiration pneumonitis
Infectious pneumonitis
Drug induced
pneumonitis
Fibrosing alveolitis
RARE:
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Pulmonary vasculitis
Pulmonary neoplasia
Pulmonary hypertension
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CARDIAC
Elev. CPK-MB
Mitral Valve prolapse
AV conduction
disturbances
Cardiomyopathy
Myocarditis
MALIGNANCY & MYOSITIS
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Controversial
Reports range from 10-25%
If real, men over age 50 yrs at greatest
risk
Common tumors: Breast, lung, ovary,
stomach, uterus, colon
60% the myositis appears 1st, 30%
neoplasm 1st, and 10%
contemporaneously
Avoid invasive, expensive searches for
occult neoplasia
RHABDOMYOLYSIS
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Injury to the sarcolemma of skeletal
muscle with systemic release of muscle
macromolecules such as CPK, aldolase,
actin, myoglobin, etc
Maybe LIFE-THREATENING: from
hyperkalemia, met. acidosis, ATN from
myoglobinuria
Common causes: EtOH, Cocaine, K+
deficiency, infection, PM/DM, infection
(clostridial, staph, strept),
exertion/exercise, cytokines
PM/DM Diagnosis
Symmetric progressive proximal
weakness
 Elevated muscle enzymes (CPK, LFTs)
 Muscle biopsy evidence of myositis
 EMG: inflammatory myositis
 Characteristic dermatologic findings
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INFLAMMATORY MYOSITIS
Treatment
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Early Dx, physical therapy, respiratory Rx
Corticosteroids : 60-80 mg/day
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80% respond within 12 weeks
Steroid resistant
Methotrexate
 Azathioprine
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IVIG, Cyclosporin, Chlorambucil: unproven
No response to apheresis
PROGNOSIS
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Poor in pts. with delayed Dx, low CPK, early
lung or cardiac findings, malignancy
Neoplasia in 10% of adults
PT for muscle atrophy, contractures, disability
Kids:50% remission, 35% chr active disease
Adult < 20 yrs. do better than >55 yrs.
Adults: Mortality rates betw. 28-47% @ 7 yrs.
Relapses & functional disability are common
Death: due to malignancy, sepsis, pulm. or
cardiac failure, and complications of therapy
Inflammatory Myositis
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Polymyositis (PM) and dermatomyositis (DM) are types
of idiopathic inflammatory myopathy (IIM). IIM are
characterized clinically by proximal muscle weakness
Etiology: There is now known etiology.
Demographics: PM is more common than DM in adults.
Peak incidence occurs between 40 and 60 yrs. F:M 2:1
Muscles: Proximal muscle weakness, dysphagia,
aspiration. respiratory failure or death.
Skin: Gottron's papules, heliotrope rash, "V" neck rash,
periungual erythema, "Mechanic's hands", calcinosis
Dx: Muscle enzymes (CPK, aldolase), EMG, Biopsy
Rx: Steroids, MTX, Azathioprine, IVIG