Approach to myopathyApproach to myopathy

Hereditary Hereditary

acquiredacquired

historyhistory

Onset ageOnset age distributiondistribution CourseCourse MyalgiaMyalgia CrampCramp Contracture Contracture Dark urineDark urine Myotonia ,Stiffness /warming up phenomenaMyotonia ,Stiffness /warming up phenomena Aggravating: exercise /diet/temperature/drugAggravating: exercise /diet/temperature/drug

examexam

Limb girdleLimb girdle ScapuloperonealScapuloperoneal DistalDistal Ocular or pharyngealOcular or pharyngeal Neck extensorNeck extensor Atrophy or hypertrophyAtrophy or hypertrophy Myotonia or paramyotoniaMyotonia or paramyotonia

Ptosis usually without opthalmoplegiaPtosis usually without opthalmoplegiaMyotonic dystrophyMyotonic dystrophy

Congenital myopathyCongenital myopathy

Ptosis with opthalmoplegiaPtosis with opthalmoplegiaOculopharyngeal muscular dystrophyOculopharyngeal muscular dystrophy

Mitochondrial myopathyMitochondrial myopathy

WeaknessWeakness Constant fluctuationConstant fluctuation

Longlife acquiredLonglife acquired MG MG periodic Pperiodic P metabolic metabolic

Progressive Progressive staticstatic Dystrophy congenitalDystrophy congenital

Age Age DistributionDistribution InheritanceInheritance

Work upWork up Muscles enzymeMuscles enzyme R/o metabolic screenR/o metabolic screen EMG&NCS (myotonia ,fibrillation, R/o EMG&NCS (myotonia ,fibrillation, R/o

neuropathy)neuropathy) Muscle biopsy (dystrophy/ congenital Muscle biopsy (dystrophy/ congenital

myopathy, stain for enzyme level)myopathy, stain for enzyme level) Genetic studyGenetic study Other :Other : Forearm exercise testForearm exercise test specific Enzymes levelspecific Enzymes level

When do you suspectWhen do you suspect??

Hereditary myopathyHereditary myopathy

Structural Structural functionalfunctional

classificationclassification

DystrophyDystrophy Congenital myopathyCongenital myopathy Channelopathies & myotoniaChannelopathies & myotonia Metabolic (fatty acid/ Metabolic (fatty acid/

glycogensis/mitochondrial)glycogensis/mitochondrial)

muscular dystrophymuscular dystrophy

are inherited myopathy characterized by are inherited myopathy characterized by progressive muscles weakness progressive muscles weakness &degeneration &subsequent replacement &degeneration &subsequent replacement by fibrous & fatty connective tissueby fibrous & fatty connective tissue

Historically were categorized by their: Historically were categorized by their: Age onset /distribution of weakness& Age onset /distribution of weakness&

pattern of inheritancepattern of inheritance The genetic mutation &abnormal gene The genetic mutation &abnormal gene

product were defined for many of themproduct were defined for many of them

MDMDdiseasediseaseinheritanceinheritanceageageproteinprotein

duchenneduchenneX linkedX linked2y2ydystrophindystrophin

beckersbeckersX linkedX linked5-155-15....

Emery-dreifussEmery-dreifussX linkedX linkedchildhchildhemerinemerin

LGDLGDAD/ARAD/ARsacroglycansacroglycan

Cong/CNSCong/CNSARARbirthbirth

Cong/noCNSCong/noCNSARAR....merosinmerosin

Distal MDDistal MDAD/ARAD/AR

bethlenbethlenADAD

FSHFSHADADChild&Child&adultadult

oculodystrophyoculodystrophyADAD55thth dec dec

Myotonic type1Myotonic type1ADAD2th,3th 2th,3th decadedecade

Myotonic type 2Myotonic type 2ADAD

myofibrillarmyofibrillarADADdesmmindesmmin

Duchenne MDDuchenne MD

Incidence: 1/3500 male birthIncidence: 1/3500 male birth 1/3 new mutation1/3 new mutation c/p:as early as 2-3y with delay c/p:as early as 2-3y with delay

milestonesmilestones Progressive limb girdle patternProgressive limb girdle pattern Fall 5-6y/difficult climb stair 8y, Fall 5-6y/difficult climb stair 8y,

confined to wheelchair 12yconfined to wheelchair 12y

Joint constructers 6-10yJoint constructers 6-10y Calf hypertrophy is earlyCalf hypertrophy is early Muscles atrophy lateMuscles atrophy late Progressive kyphscliosis due to Paraspinal Progressive kyphscliosis due to Paraspinal

muscles weaknessmuscles weakness Reflex: biceps/knee/lost by age 10yReflex: biceps/knee/lost by age 10y ankle preserved late in diseaseankle preserved late in disease Respiratory s/s after age 10 Respiratory s/s after age 10

Cardiac: generally asymptomaticCardiac: generally asymptomatic CHF, arrhythmia lateCHF, arrhythmia late 90% abnormal ECG :tall rt R 90% abnormal ECG :tall rt R

wave,deep left Q wavewave,deep left Q wave Echo: hypokinesia ,dilatation of Echo: hypokinesia ,dilatation of

ventricular wallventricular wall GI: intestinal pseudo obstructionGI: intestinal pseudo obstruction IQ: one SD below NIQ: one SD below N

lablab A dystrophin gene deletion can be detected by:A dystrophin gene deletion can be detected by: DNA analyses from leukocytes by PCR in 2/3 DNA analyses from leukocytes by PCR in 2/3

patient or DNA musclespatient or DNA muscles The other 1/3 DX by… muscles biopsy( dystrophin The other 1/3 DX by… muscles biopsy( dystrophin

def by stain &WB ,typical features of MD)def by stain &WB ,typical features of MD) CK:20-100 XN ,decline laterCK:20-100 XN ,decline later EMG:myopathic &fibrillationEMG:myopathic &fibrillation Note :if DNA study +ve no need for EMG Note :if DNA study +ve no need for EMG

&muscles biopsy&muscles biopsy

Beckers MDBeckers MD

Is milder form Is milder form 5/100,0005/100,000 Age :5-15yAge :5-15y Wheelchair at 30yWheelchair at 30y Cardiac similar to duchenneCardiac similar to duchenne Death by age 40Death by age 40 Dx: DNA, muscle biopsy decrease in Dx: DNA, muscle biopsy decrease in

dystrophindystrophin CK:moderatly elevatedCK:moderatly elevated

treatmenttreatment

No treatment prevent the No treatment prevent the progression progression corticosteroid :controlled trial with corticosteroid :controlled trial with predinsone 0,75mg/kg demonstrate predinsone 0,75mg/kg demonstrate moderate improvement in strength moderate improvement in strength &delay progression to wheel chair& &delay progression to wheel chair& respiratory compromiserespiratory compromise

Emery-dreifussEmery-dreifuss

X linkedX linked onset :childhoodonset :childhood Triad of: Triad of:

1-early contracture 1-early contracture elbow, ankle &posterior cervicalelbow, ankle &posterior cervical

2-progressive scapulohumroperoneal2-progressive scapulohumroperoneal

3-cardiomyopathy with atrial conduction 3-cardiomyopathy with atrial conduction defectdefect

CK :normal to or only moderate CK :normal to or only moderate elevatedelevated

The muscle biopsy :myopathic The muscle biopsy :myopathic &fewer dystrophic&fewer dystrophic

DNA:mutation gene in Xq28 code for DNA:mutation gene in Xq28 code for protien emerinprotien emerin

Limb girdle dystrophyLimb girdle dystrophy

AR majorityAR majority Onset: adolescence or lateOnset: adolescence or late

childhood: sever child recessive muscular childhood: sever child recessive muscular dystrophydystrophy

AR: defect in sacroglycan component of AR: defect in sacroglycan component of the DGC( sacroglycanopathythe DGC( sacroglycanopathy((

Alpha sacrglycan adhelin is account for Alpha sacrglycan adhelin is account for 20%20%

Onset:childhood& variableOnset:childhood& variable No intellectual impairment or cardiacNo intellectual impairment or cardiac Muscle biopsy :immune stain absent or Muscle biopsy :immune stain absent or

diminished for sacroglycandiminished for sacroglycan

AD: onset: second and third decadesAD: onset: second and third decades Protein defect:caveolin-3Protein defect:caveolin-3

There are multiple subtypesThere are multiple subtypes AD type 1:1A,1B …AD type 1:1A,1B … AR type 2:AR type 2:

Congenital muscular dystrophyCongenital muscular dystrophy ARARPerinatal onset Perinatal onset c/p:hypotonia &proximal weakness,arthrogryposisc/p:hypotonia &proximal weakness,arthrogryposis Two types Two types CNS involvement: severCNS involvement: sever mental mental

retardation ,visual, seizure ..cerebrocular retardation ,visual, seizure ..cerebrocular dysplasia, progressive death by age 10-12dysplasia, progressive death by age 10-12

No CNS :classic typeNo CNS :classic type MRI (hypomyelination), MRI (hypomyelination), benign outcome, non progressivebenign outcome, non progressive

Muscle biopsy :dystrophy… Muscle biopsy :dystrophy…

FSHFSH InheritanceInheritance: AD: AD Variable expression within the familiesVariable expression within the families AgeAge: childhood or adult life: childhood or adult life C/PC/P: :

weakness early facial then descending to scapula stabilizer weakness early facial then descending to scapula stabilizer muscles &muscles of the upper limb& distal muscles &muscles of the upper limb& distal weakness ..peroneal ,the rate of progression to forearm weakness ..peroneal ,the rate of progression to forearm &pelvic girdle &pelvic girdle

Asymmetrical/Asymmetrical/ deltoid preserved / joint contracture are deltoid preserved / joint contracture are uncommonuncommon

Popeye handPopeye hand/ winging scapula/ / winging scapula/ no muscle hypertrophyno muscle hypertrophy Early onset worse prognosisEarly onset worse prognosis 20% require wheelchair20% require wheelchair

Work upWork up

CK:N or mild elevationCK:N or mild elevation Muscles biopsy: myopathic Muscles biopsy: myopathic

dystrophicdystrophic& occasionally prominent & occasionally prominent mononuclear infiltratemononuclear infiltrate

Gene: ch 4q35 gene deletion Gene: ch 4q35 gene deletion

Myotonic dystrophyMyotonic dystrophy AD, AD, CTG repeatCTG repeat Affect : Affect :

skeletal,cardiac, smooth muscles, eye,endocrine skeletal,cardiac, smooth muscles, eye,endocrine &brain&brain

Onset :at any age ,usually at late 2Onset :at any age ,usually at late 2ndnd decade decade Some individual can be symptoms free their Some individual can be symptoms free their

entire lifeentire life Sever form :congenital myotonic dystrophySever form :congenital myotonic dystrophy

C/P:weakness: C/P:weakness: (facial,temporalis wasting,ptosis,neck (facial,temporalis wasting,ptosis,neck flexor,distal weakness progress to flexor,distal weakness progress to involve limb girdle)involve limb girdle)

Weakness >myotoniaWeakness >myotonia May be areflexicMay be areflexic

systemicsystemic

Posterior sub scapular cataractPosterior sub scapular cataract Testicular atrophy& impotenceTesticular atrophy& impotence Intellectual impairmentIntellectual impairment Hypersomnia (central & obstructive)Hypersomnia (central & obstructive) Respiratory failureRespiratory failure Elevation of serum glu, rarely frank DMElevation of serum glu, rarely frank DM GI: dysphagea, pseudo obstructionGI: dysphagea, pseudo obstruction Cardiac conduction defect sudden deathCardiac conduction defect sudden death Fetal loss in femaleFetal loss in female

PROMMPROMM

ADAD Proximal weakness, no distal Proximal weakness, no distal

weaknessweakness Myotonia &myalgiaMyotonia &myalgia Less cardiac &other organ Less cardiac &other organ

involvement except cataractinvolvement except cataract

Work upWork up

CK:N or mild elevationCK:N or mild elevation EMG: myopathic & EMG: myopathic & myotoniamyotonia Muscle biopsy: atrophic, non specificMuscle biopsy: atrophic, non specific Gene :CTG repeat >50 in ch19q13.2Gene :CTG repeat >50 in ch19q13.2

tttttt

Myotonia rarely sever to require tt: Myotonia rarely sever to require tt: phenytoin is the only safe drugphenytoin is the only safe drug

Annual ECG ..pacemaker may Annual ECG ..pacemaker may requiredrequired

Positive pressure ventilation supportPositive pressure ventilation support High risk in surgery (cardiac High risk in surgery (cardiac

&respiratory)&respiratory) Sedation & opiod use with cautionSedation & opiod use with caution

Distal dystrophyDistal dystrophy

TypesTypes AD:4AD:4thth &6 &6thth decade decade AR:in early adult onset/late second or AR:in early adult onset/late second or

early 3early 3rdrd CK :elevated 200xN ARCK :elevated 200xN AR

oculopharengealoculopharengeal ADAD Onset:5Onset:5thth &6 &6thth decade decade Ptosis &dysphagea later all extra ocular Ptosis &dysphagea later all extra ocular

muscles &extremities affected (limb muscles &extremities affected (limb girdle) but distal can be significant in some girdle) but distal can be significant in some variantvariant

Slow progressive ,death from aspiration Slow progressive ,death from aspiration pneumonia or starvationpneumonia or starvation

Ck:n or mild elevatedCk:n or mild elevated Muscle biopsy :Muscle biopsy :rim vacuolesrim vacuoles Genetic GCG repeat in ch14Genetic GCG repeat in ch14

Congenital myopathyCongenital myopathy

Are distinguished from dystrophy in Are distinguished from dystrophy in threethree respect:respect:

Characteristic morphologic alterationCharacteristic morphologic alteration At birthAt birth Non progressiveNon progressive However there are exception to all However there are exception to all

these generalizationthese generalization Inheritance: are variableInheritance: are variable

c/p: c/p: hypotonia with subsequent developmental delayhypotonia with subsequent developmental delay Reduce muscles bulk, slender body build &long narrow face Reduce muscles bulk, slender body build &long narrow face Skeletal abnormalities: high arched palate ,pectus Skeletal abnormalities: high arched palate ,pectus

exacavitum, kyphscliosis, dislocated hip, pes cavusexacavitum, kyphscliosis, dislocated hip, pes cavus))

Absent or reduced muscle stretch reflexAbsent or reduced muscle stretch reflex

Weakness: limb girdle mostly, butWeakness: limb girdle mostly, but distal distal weakness existweakness exist CK &EMG may be normalCK &EMG may be normal Muscle biopsy: the diagnostic methodMuscle biopsy: the diagnostic method

Central core myopathyCentral core myopathy

Characterized by discrete zones of Characterized by discrete zones of myofibrillar disruption in the center myofibrillar disruption in the center of muscles fiberof muscles fiber

AD but can be sporadicAD but can be sporadic Mutation ch 19,similar to malignant Mutation ch 19,similar to malignant

hyperthermia patienthyperthermia patient So anesthesia precaution are So anesthesia precaution are

necessarynecessary

Nemaline myopathyNemaline myopathy Pathology: thePathology: the presence of rods or presence of rods or

melamine bodies within muscles fibermelamine bodies within muscles fiber AD or ARAD or AR c/p:c/p: Sever neonatalSever neonatal form which is fatal in the form which is fatal in the

first year of lifefirst year of life Mild staticMild static Slowly progressiveSlowly progressive from birth or early from birth or early

childhoodchildhood Note :rods can present in HIV related Note :rods can present in HIV related

myopathy ,some inflammatorymyopathy ,some inflammatory

Centro nuclear (myotubular)Centro nuclear (myotubular)

Pathology: large central nuclei in the Pathology: large central nuclei in the muscle fibermuscle fiber

X linked/AD/ARX linked/AD/AR sever neonatal/static or slowly sever neonatal/static or slowly

progressiveprogressive c/p: ptosis & opthalmoparesisc/p: ptosis & opthalmoparesis Genetic defect: mutation in Genetic defect: mutation in

myotubularin gene Xp28myotubularin gene Xp28

Metabolic myopathyMetabolic myopathy

Metabolic myopathyMetabolic myopathy

Glucose/glycogen metabolismGlucose/glycogen metabolism Fattay acid metabolismFattay acid metabolism Purine nucleotidePurine nucleotide mitochondrialmitochondrial

Metabolic myopathyMetabolic myopathy

Clues to hereditary metabolic Clues to hereditary metabolic myopathymyopathy

Excersize induce weakness Excersize induce weakness &myoglobinuria…glycogen &lipid&myoglobinuria…glycogen &lipid

Part of diffuse neurological Part of diffuse neurological syndrome…mitochondrialsyndrome…mitochondrial

Glucose/glycogenGlucose/glycogen

Glucose &its storage is essential for the Glucose &its storage is essential for the short termshort term anaerobic energy (glycogensis)anaerobic energy (glycogensis)

Two clinical presentation:Two clinical presentation: 1-dynamic:type V/V11/V111/1X//XX11-dynamic:type V/V11/V111/1X//XX1 2-static:fix weakness2-static:fix weakness

1/111/1V1/111/1V Inheritance:AR except for Inheritance:AR except for

phosphoglycerate kinasephosphoglycerate kinase

Glycogensis with exerciseGlycogensis with exercise intolerance intolerance C/P: exercise intolerance in the childhood C/P: exercise intolerance in the childhood

followed by excertional induced muscle pain followed by excertional induced muscle pain &myoglobinurea in sec or 3&myoglobinurea in sec or 3rdrd decade.. decade..

(Second wind phenomena)(Second wind phenomena) work up: CK/EMG work up: CK/EMG

normal between the attack in early stage but normal between the attack in early stage but after attack( myopathic &fibrillation)after attack( myopathic &fibrillation)

Forearm exercise testForearm exercise test Enzyme assayEnzyme assay Muscle biopsyMuscle biopsy Genetic for mutation Genetic for mutation

What is 0ther causes of What is 0ther causes of myoglobinureamyoglobinurea??

Glycogensis with fixed weaknessGlycogensis with fixed weakness

Acid maltase deficiency:Acid maltase deficiency: Enzyme convert glycogen to glucoseEnzyme convert glycogen to glucose Three clinical variant:Three clinical variant: Infantile: pompes: progressive Infantile: pompes: progressive

weakness ,enlargement of heart, tongue &liverweakness ,enlargement of heart, tongue &liver death by age 2death by age 2

Juvenile type: proximal weakness, may calf Juvenile type: proximal weakness, may calf hypertrophy death by age 20 from respiratory hypertrophy death by age 20 from respiratory failurefailure

Adult type:2&7Adult type:2&7thth progressive limb girdle or progressive limb girdle or scapuloperoneal .no liver ,no heart scapuloperoneal .no liver ,no heart involvementinvolvement

Work upWork up

CK :moderately increasedCK :moderately increased EMG: myopathic changes &EMG: myopathic changes &myotonic myotonic

discharge in paraspinusdischarge in paraspinus Enzyme assay:Enzyme assay: Muscle biopsy: a vacuolar myopathy Muscle biopsy: a vacuolar myopathy

with high glycogen contentwith high glycogen content Genetic: mutation in ch 17Genetic: mutation in ch 17

Fatty acid metabolismFatty acid metabolism

Lipids are essential for aerobic Lipids are essential for aerobic metabolismmetabolism

Dynamic & staticDynamic & static CPT:carnitine palmitoyl transeferase CPT:carnitine palmitoyl transeferase

deficiencydeficiency Carnitine deficiencyCarnitine deficiency

CPTCPT Type 1:infancy &child hood with hepatic Type 1:infancy &child hood with hepatic

dysfunctiondysfunction Type 2:exertional myalgia &myoglobinurea, Type 2:exertional myalgia &myoglobinurea,

it is the most frequently definable it is the most frequently definable metabolic defect presenting with myoglobinureametabolic defect presenting with myoglobinurea

AR ,gene 1p32AR ,gene 1p32 The attacks occur after prolonged exercise, The attacks occur after prolonged exercise,

fasting, febrile illnessfasting, febrile illness Unlike mecardle disease the patient can tolerate Unlike mecardle disease the patient can tolerate

brief exercise ,no second wind phenomenabrief exercise ,no second wind phenomena Muscle strength are normal at restMuscle strength are normal at rest

lablab

CK:n at restCK:n at rest Forearm exercise test :NForearm exercise test :N EMG: n at rest ,&myopathic during the EMG: n at rest ,&myopathic during the

attackattack Muscle biopsy: usually N ,except of Muscle biopsy: usually N ,except of

myopathic changes after rhabdomylsismyopathic changes after rhabdomylsis Enzyme assayEnzyme assay ttt &meal frequency: increase CHO intakettt &meal frequency: increase CHO intake

&education about fasting &exercise&education about fasting &exercise

MitochondrialMitochondrial Kearns-sayer: Kearns-sayer: opthalmoplegia, retinitis pigmentosa, heart opthalmoplegia, retinitis pigmentosa, heart

block, hearing loss, short stature, ataxia, delayed 2block, hearing loss, short stature, ataxia, delayed 2ndnd sexual sexual characteristic, PN, respiratory characteristic, PN, respiratory

MERFMERF: myoclonic epilepsy, generalized seizure, ataxia, : myoclonic epilepsy, generalized seizure, ataxia, dementia, hearing loss, optic atrophy ,PN, cardiomyopathy dementia, hearing loss, optic atrophy ,PN, cardiomyopathy &cutenous lipoma&cutenous lipoma

MNGLEMNGLE: mitochondrial neurogastrointestinal : mitochondrial neurogastrointestinal encephalomyopathyencephalomyopathy

POLIP :POLIP :polyneuropathy,opthalmoplasia,leukoencephalopathpolyneuropathy,opthalmoplasia,leukoencephalopathy& intestinal pseudo obstructiony& intestinal pseudo obstruction

channelopathychannelopathy

Non dystrophic myotoniaNon dystrophic myotonia Periodic paralysisPeriodic paralysis It due to mutation in different It due to mutation in different

channels gene leading to :channels gene leading to : Hyper excitability :myotoniaHyper excitability :myotonia In excitability: paralysisIn excitability: paralysis

Chloride channelopathyChloride channelopathy

Mutation in CL Mutation in CL channel..hyperexcitability after channel..hyperexcitability after depolarizationdepolarization

Myotonia congenita:Myotonia congenita: AD..thomsen /AR:beckerAD..thomsen /AR:becker C/P:C/P:

muscle hypertrophy, muscle hypertrophy, myotonia/becker type has fluctuating myotonia/becker type has fluctuating limb girdle weaknesslimb girdle weakness

Sodium channleopathySodium channleopathy ADAD Onset: first decadeOnset: first decade Phenotypic types:Phenotypic types: Paramyotonia congenitaParamyotonia congenita

Hyperkalemic periodic paralysisHyperkalemic periodic paralysis

myotonia :Potassium sensitive disorder : myotonia :Potassium sensitive disorder : myotonia fluctuant myotonia fluctuant

myotonia permanentmyotonia permanent acetazolamide responsive myotoniaacetazolamide responsive myotonia

Calcium channelopathyCalcium channelopathy

HypokalemicHypokalemic

malignant hyperthermiamalignant hyperthermia

C/P of channelopathyC/P of channelopathy

Paramytonia congenitaParamytonia congenita

ADAD Onset :1Onset :1stst decade decade Paradoxical myotonia (Aggravated by Paradoxical myotonia (Aggravated by

warm as well cold)warm as well cold) Face ,neck,forearmFace ,neck,forearm After several attempt of eye closure the After several attempt of eye closure the

patient can not open the eyepatient can not open the eye ttt: Na channels blocker mexiletinettt: Na channels blocker mexiletine

Hyperkalamic periodic paralysisHyperkalamic periodic paralysis K sensitive periodic paralysisK sensitive periodic paralysis Onset :1Onset :1stst decade decade Attack last:1-2 hAttack last:1-2 h During attack: areflexic with no ocular or During attack: areflexic with no ocular or

respiratory muscles weaknessrespiratory muscles weakness Strength is n between the attack, but some Strength is n between the attack, but some

patient has interictal limb girdle weaknesspatient has interictal limb girdle weakness Some families have myotonia &paramyotoniaSome families have myotonia &paramyotonia Aggravated: fasting/cold, shortly after exercise, K Aggravated: fasting/cold, shortly after exercise, K

load, early AMload, early AM

Episodes are rarely serous enough to Episodes are rarely serous enough to require acute tttrequire acute ttt

ttt: ttt: oral CHO oral CHO Prevention: thiazide,B agonist, low Prevention: thiazide,B agonist, low

K,high CHOK,high CHO Avoid fasting, strenuous exercise/Avoid fasting, strenuous exercise/

myotoniamyotonia

No weaknessNo weakness Aggravated by K diet/ excretionAggravated by K diet/ excretion Can response to acetazolamideCan response to acetazolamide

hypokalemiahypokalemia

AD:AD: It is the most frequent form of periodic It is the most frequent form of periodic

paralysisparalysis Common in maleCommon in male Age: adolescenceAge: adolescence The attacks 3-24h/vague prodorme of The attacks 3-24h/vague prodorme of

stiffness &heaviness& rarely ocular, stiffness &heaviness& rarely ocular, bulbar, respiratory involvedbulbar, respiratory involved

Early Myotonia of eyelid & late interictal Early Myotonia of eyelid & late interictal proximal weakness proximal weakness

AggravatedAggravated: CHO meal, cold,hrs post : CHO meal, cold,hrs post exercise, sleepexercise, sleep

Work up:K level q 30min /TFT/ Work up:K level q 30min /TFT/ R/O 2R/O 2ndnd causes of hypokalemia causes of hypokalemia Tttt:Tttt: Acute: Acute: oral K Q30min ,if symptoms sever oral K Q30min ,if symptoms sever

iv Kiv K Prevention:Prevention: Low CHO, low sodium Low CHO, low sodium

diet ,spirnolactone, trimetrinediet ,spirnolactone, trimetrine