Myopathy and muscular dystrophy Dr. abeer kawther

Myopathy: All 1ry dis. of muscles. -genetically determined -congenital -metabolic -drug induced -inflamatory Genetically determined myopathy Muscular dystrophy: Progressive degeneration of groups of muscles, symmetrical, no fasciculation, reflexes preserved, no loss of sensations, normal nervous system.

Types: Duchenne dyst. Spinal muscular dyst.: -Werding-Hoffman -Kugelberg-Welander -Adult forms Duchenne dyst.: - incidence 20-30\100,000 live male births -x-linked recessive -65% mothers carriers -Abn. Sarcolemma ingress of ca muscle necrosis

Clinical features: - presentation 1-3 yrs of age -delayed motor development, frequent falls,inability to run -affection of proxymal muscles of L.L. &then of U.L. Starts by pseudohypertrophy &later contractures -Gower`s manover, waddling gait -death at age of20 from resp. infection -intellect affected in 20%of cases Becker dystrophy: Milder form of Duchenne

Spinal muscular atrophy Death of ant. Horn cell of unknown cause Adult forms: 1-Limb girdle type(scapulohumeral): - autosomal ressive -2 nd &3 rd decade -starts in shoulder or pelvic girdle & later involves both 2-Facioscapulohumeral(Landozy-Dejerne): - autosomal dominant -any age -1 st facial muscle then shoulder girdle &later pelvic girdle -compatible with long life

Investigation for muscular dystrophy -EMG -Muscle biopsy -CPK &aldolase Management -no -Co enzyme Q 10 - physiotherapy &orthop[dic measers

Myotonic disorders Consists of slow relaxation of muscles 1)Myotonia dystrophica 2)Myotonia congenita Myotonia dystrophica: - autosomal dominant - presentation at adult life -ptosis, wasting of temporalis, sternomastoids, arms, legs -associated with :cataracts, frontal baldness, testicular or ovarian atrophy -death from cardiac or resp. insufficincy

Diagnosis - EMG - muscle biopsy - dis. Located at long arm of chromosome 19 Management Prcainamide, quinine, phenytoin Congenital myotonic dystrophy: Babies born to mothers with myotonia dystrophica Myotonia congenita - autosomal domoninant or ressive -begins early in childhood

Congenital myopathy -Central cor disease -Nemaline myopathy Metabolic myopathy -thyrotxicosis -cushing -familial periodic paralysis -Glycogen storage dis. -mitrochondrial dis.

Drug induced Lithium, betablockers, alcohol, steroids Inflamatory myopathy Viral myositis Connective tissue dis. - polymyositis \ dermatomyositis -polymyalgia rhumatica