Approach to myopathy
description
Transcript of Approach to myopathy
Approach to myopathy
Dr omid yaghini
MUSCLES DISORDERS
Definition:
Diseases involving the muscle fibers (myogenic)Unlike: neuronopathies: secondary to LMN Heterogenous etiology, genotype, phenotype…
No specific treatment for most of them
Myoblasts fusing to form large multi-nucleate muscle cells
white = fast (speed)
red = slow (endurance)
ETIOLOGY / CLASSIFICATIONInherited myopathies
– Muscular dystrophies – Congenital myopathies– Inherited channelopathies – Periodic paralysis – Inherited metabolic myopathies
Disorders of glycolysis Disorders of oxidative metabolism Lipid myopathies Mitochondrial myopathies
Acquired myopathies Inflammatory myopathies
Acquired metabolic myopathies
Toxic myopathies
Weakness Constant fluctuation
Longlife acquired MG periodic P metabolic
Progressive static Dystrophy congenital
muscular dystrophy are inherited myopathy characterized by
progressive muscles weakness °eneration &subsequent replacement by fibrous & fatty connective tissue
Historically were categorized by their: Age onset /distribution of weakness&
pattern of inheritance The genetic mutation &abnormal gene
product were defined for many of them
MDprotein age inheritance disease
dystrophin 2y X linked duchenne.. 5-15 X linked beckers
emerin childh X linked Emery-dreifusssacroglycan AD/AR LGD
birth AR Cong/CNSmerosin .. AR Cong/noCNS
AD/AR Distal MDAD bethlen
Child&adult
AD FSH
5th dec AD oculodystrophy
2th,3th decade
AD Myotonic type1
AD Myotonic type 2desmmin AD myofibrillar
Congenital myopathy Are distinguished from dystrophy in
three respect: Characteristic morphologic alteration At birth Non progressive However there are exception to all
these generalization Inheritance: are variable
c/p: hypotonia with subsequent developmental delay Reduce muscles bulk, slender body build &long narrow face Skeletal abnormalities: high arched palate ,pectus
exacavitum, kyphscliosis, dislocated hip, pes cavus) Absent or reduced muscle stretch reflex Weakness: limb girdle mostly, but distal weakness exist CK &EMG may be normal Muscle biopsy: the diagnostic method
Metabolic myopathy Glucose/glycogen metabolism Fattay acid metabolism mitochondrial
Calf Pseudohypertrophy
Gowers' Sign
“Climbing up himself”
Gowers’ sign always denotes proximal muscle weakness
Clinical: Muscle weakness: main feature
Gower’s sign (proximaly dominating deficit)Contractures +/- severe: advanced stagesPain: in inflamm. Disorders onlyAtrophy (+/- pseudohypertrophy in X-linked) Deformity: advanced diseaseDTR: normal, diminished or absentTone: slightly or normal Other systems may be involved
Common Features:
Common Features:
Laboratory Investigations:
CBC, LFT.. Normal ESR: high in inflammatory only U&E: abnormalities in some endocrinopathies and
periodic paralysis C.K & aldolase: generaly: raised (normal in few
sittings: metabolic, endocrine…) Lactic acid Genetic study: location & type of chromozomal
abnormalities:
Common Features:
Neurophysiology
NCS: normalEMG:
– Spontaneous activities +/- in inflammatory disorders– Interferential tracing
– MUPs: small A Short D
polyphsics