医药临床护理Musculardiseasesppt课件

《医药临床护理Musculardiseasesppt课件》由会员分享，可在线阅读，更多相关《医药临床护理Musculardiseasesppt课件（68页珍藏版）》请在装配图网上搜索。

1、MusculardiseasesMyastheniagravisDefinition:Myastheniagravisiscausedbyadefectofneuromusculartransmissionduetoanantibody-mediatedattackuponnicotinicacetylcholinereceptors(AChR).ClinicalCharacter:FluctuatingweaknessImprovedbyinhibitorsofcholinesteraseEtiologyandPathogenesisRelatedtodestructiveeffectsof

2、autoantibodiestoAChREvidence:1.Experimental immunization of animalswith purified AChR from an electric fish,induces high titers of antibody to thereceptor.2.HumanserumantibodiesthatreactwithhumanAChRwerefoundinMGpatients3.Electrophysiologic features of MG wereproducedbypassivetransferofhumanIgGtomic

3、e.4.Plasmapheresisreducedplasmalevelsofanti-AChR and ameliorated myasthenicsymptomsandsigns.Howtheautoimmunedisorderstartsisnotknown.InhumanMG,hyperplasiaofthethymusabout15%ofcasesisathymoma.AChRantibodiesaresynthesizedbyBcellofhyperplasticthymusgland.Whenhumanmyasthenicthymuswastransplantedintomice

4、,theanimalproducedantibodiestoAChRthatboundtotheirownmotorend-plates.A.Primarilyinthethymus.1.70%ofthymusglandfromadultMGpatientsarenotinvoluted.2.Thethymusweighmorethannormal.3.The thymus glands show lymphoidhyperplasia.4.Immunocytochemical:germinalcenterscontainBcells,plasmacells,andTcells.Patholo

5、gy5.10%of myasthenic thymus glandscontainthymomas.B.Loss of synaptic folds and widenedcleftsC.Somenerveterminalsaresmallerthannormal.D.On residual synaptic folds show Y-shapedantibody-likestructures,IgG.Clinicalfeatures1.Incidence:0.4/100,000.Prevalence:5/100,000.Beforeage40,Male:female3:12.Symptoms

6、:Threeclinicalcharacteristics.1)Thefluctuatingnature:Theweaknessvaries in a single day;day to day;or overlongerperiods.(remissionsorexacerbations).Crisis:When an exacerbation involvesrespiratorymuscles2)Thedistributionofweakness:A.Ocularmusclesareaffectedfirstinabout40%ofthecases(Ptosisanddiplopia).

7、B.Affected facial oropharyngeal muscles(dysarthria,dysphagia and limination offacialmovements).C.Limbandneckweakness.Crisis:occurin:oropharyngealrespiratorymuscleweakness.provokedby:respiratoryinfectionsurgicalproceduresemotionalstresssystemicillness3).Thethirdcharacteristicistheclinical response to

8、 cholinergicdrugs.Thisoccurssouniformlythatithasbecomepartofthedefinition.3.Signs:(1)The vital signs and general physicalexamination are normal limits,unless thepatientisincrisis.(2)Weakness of the facial and levatorpalpabraemusclesproducesacharacteristicexpressionlessfaceswithdroopingeyelids.(3).Co

9、mpleteophthalmoplegiainoneorbotheyes(diplopia).Thepupilisneverinvolved.(4).Weakness of oropharyngeal or limbmuscles,andrespiratorymuscle.(5).Sensationisnormalandthereflexesarepreserved.1.Classification:(1)Group1.About14%ofpatientshaveocularmyastheniaonly.(2)GroupIIA.Mildgeneralizedmyastheniawithocul

10、arsigns.(3)Group IIB.Moderately severe generalizedmyasthenia,with mild bulbar and ocularinvolvement.(4)Group III.Acute severe myasthenia,withbulbarandrespiratory complications.Tracheostomyisrequired.(5)GroupIV.Lateseveremyasthenia,usuallydevelopingfromothergroupswithin2years.1.Routineexaminationsofb

11、lood,urine,andCSFarenormal.2.EMG:90%patients have progressivedecrementintheamplitudeofmuscleactionpotentialsevokedbyrepetitivenervestimulationat3to5Hz.Laboratorytests3.AchRAntibodiestoarefoundin90%ofpatientsofallages.Thetiterdosenotmatchtheseverityofsymptoms.4.CTscansofthemediastinumdemonstrates thy

12、momas,especially inthoseolderthan40.Diagnosis1.Characteristichistoryandphysicalexamination.2.Jollytest3.Edrophonium(Tension)tests.4.Neostigminetest:0.04mg/kg,IM,reachesitsmaximum activity in 1-2 hours.Theeffectisgoneat3-4hours.5.EMG.6.AntibotiestoAchRtest.7.CT scans of thymus.Hyperplasia orthymoma.D

13、ifferentialdiagnosis:1.Botulism:presynapticblockerofacetylcholinereleasecausedbycontaminatefoodsprogressivemuscleweaknessBeginning:extraocularpharyngealmusclesTreatment:trivalentantitoxinguanidinehydrochloride2.Lambert-Eatonsyndrome(LEMS):Myasthenia-likesyndromeoccurswithcarcinomaGeneralizedmusclewe

14、aknessThe EMG is helpful in differentiating thesyndromefromtruemyastheniagravis.Treatment with removal of the tumor andguanidinehydrochloride.Treatment1.Anticholinesterasetherapy:Anticholinesterase drug should be given assoonasthediagnosisismade.i.Pyridostigmine60mgqidii.Neostigminebromide15mgqidiii

15、.Ifthepatientshavedifficultyeating,dosescanbetakenabout30minutesbeforeameal.2.Corticosteroidtherapy(1).High-dosecoticosteroidtherapy1).Prednisone,60-100mgdaily.Improvementbeginsatabout12days.2).Dexamethasone,20mgdailyIVfor10days.3).Prednisononmethel,480-1000mgdailyIVfor3-5days.(2).Low-dosecorticoste

16、roidtherapy:prednisone25mg,qod,graduallyincreasingthedosageby12.5mgeveryweekuntilthetotal dosage reaches 100 mg on alternatedays.3.Immunotherapy(1).Azathioprine,50-100mg,twiceaday.(2).Cyclophophamide100mg,twiceaday.3.Thymectomy:About80%ofpatientswithoutthymomabecomeasymptomaticorgotocompleteremissio

17、nafterthymectomy.4.Plasmapheresis:Toremovetheharmfulantibody.6.Treatmentofcrisis(1).Myastheniccrisis:needassistedventilationabout10%ofmyasthenicpatientsoccur,occur in patients with dysarthria,dysphagia,respiratorymuscleweakness,respiratoryinfection,andmajorsurgerycausedbylessanticholinesterasedrugsd

18、osage.(2).Cholinergiccrisis:overdosageofanticholineserasedrugscholinergicsideeffects,excessiveanticholinesterasetherapy.(3).Brittlecrisis:Chronic anticholinergic drugs damages thesynapse,somepatientsbecomerefractorytothemedication.Crisisisanemergency.The patients respiratory function must bemaintain

19、edsameasrespiratoryfailuretreatmentCholinergicdrugdiscontinuedinafewdaysorweeks.The therapeutic goal is to maintain vitalfunctionsandtoavoidortreatinfection.3.DrugsofavoidedDrugsthathavemildneuromuscularblockingeffectsandsedatives,arecontraindicated.Quinine,Quinidine,Procainamide,Propranolol,Lidocai

20、ne,Aminoglycosideantibiotics,Polymyxin,Viomycin,Colistin,Morphine,Bubiurates,andothertranquilizers.8.Amongthetreatment,anticholinesterasegrugtherapyandplasmapheresisaresymptomatictreatmentsthymectomy,steroids,andotherimmunosuppressivedrugsmayalterthecourseofthedisease.Periodicparalysischaracterizedb

21、outsoflimbweakness.someformshavebeenmappedtothegeneforthe apha subunit of the sodium channel ofmuscleregardas“channelopathies.”Thetwomaintypeswerefirstseparatedbythelevelofserumpotassium.HypokalemicperiodicParalysisThe potassium content decreases in aspontaneousattacktovaluesof3.0mEq/Lorlower.Attack

22、smaybeinduced:injectonofinsulin,orglucose,ingestionofamealhighincarbohydrates.Incidence:Male:female,3:1autosomedominantheredityThefirstattackusuallyoccursatpuberty,butitmayoccurastheageof4ordelayedtothesixthdecade.SymptomsandSigns:attackusuallybeginsafterrest.Itcommonlydevelopsduringthenightparalysi

23、svariesfromslightweaknessofthelegtocompleteparalysisTheoropharyngealandrespiratorymusclesareusuallyspared.Theremayberetentionofurineandfecesduringasevereattack.Attackvariesfromafewhoursto24hours.Theintervalbetweenattacksmaybeoneyear,oroneormoreattacksmayoccurdaily.Weaknessisespeciallybepresentonthem

24、orningaftertheingestionofahigh-carbohydratemealbeforeretiringonthepreviousnight.Intervalbetweenattacks,patientsarestrongandserumpotassiumnormal.In a mild attack,tendon reflexes and electricalreactionsarediminished.Insevereattacks,tendonandcutaneousreflexesare absent and muscles do not respond toelec

25、tricalstimulation.Cutaneoussensationisnotdisturbed.Fatalities are rare,but death may occur fromrespiratoryparalysis.Diagnosis:transientattacksofweakness.confirmed by finding low potassium,highsodiumcontentintheserumduringanattack,orbyinducinganattackwithIVglucose(100g)andregularinsulin(20units).Trea

26、tment1.Acute attacks,rapidly terminated byingestionof20to100mEqofpotassiumsalts.Thebasisoftherapyisoraladministrationofacetazolamide,250to1000mgdaily.Thisregimenpreventsattacksinabout90%2.spironolactonepromoteretentionpotassium.Patientswiththyrotoxicperiodicparalysisarespontaneousorinducedattacksdur

27、ingtheperiodofhyperthyroidism.Glucoseandinsulinareusefulintheinterimbetweentreatmentofhyperthyroidismbydrugsorradioiodine,beforetheeuthyroidstatereturns.HyperkalemicPeriodicParalysisCharacterizedonsetbeforeage10attackstooccurinthedaytimeandtobeshorterandlesssevereMyotoniaisdemonstrablebyEMGMyotonic

28、lid-lag is the sole clinicalevidenceofthetrait.The serum and urinary potassium contentmaybeincreasedduringanattack,thismaybeduetoleakageofpotassiumfrommuscle.The attacks tend to be precipitated byhunger,rest,andcoldandbyadministrationofpotassiumchoride.Attacksmaybeterminatedbyadministrationofcalcium

29、gluconate,glucose,andinsulin.Acetazolamide,250 mg to 1000 mg daily,hasbeeneffectiveinreducingthenumberofattacksorinabolishingthemaltogether.ProgressiveMuscularDystrophiesDefinition:A muscular dystrophy has fiveessentialcharacteristics.1.defined by clinical,histologic,and EMGcriteria.No signs of dene

30、rvation or sensory loss,unlessthereisaconcommitantandseparatedisease.2.symptoms include limb or cranial muscleweakness.(Theheartandvisceralmusclesmayalsobeinvolved.)3.Symptomsbecomeprogressivelyworse.4.Histologicchangesimplydegenerationandregeneration of muscle,but no abnormalstorageofmetabolicprodu

31、ctisevident.5.This disease is recognized as heritable,even if there are no other cases in theparticularfamily.Classification.Therearefourmaintypes:Duchennemusculardystrophy(DMD)Facioscapulohumeralmusculardystrophy(FSHD)limb-girdlemusculardystrophy(LGMD)myotonicmusculardystrophyEachtypediffersfromthe

32、othersinageatonset,distributionofweakness,rateofprogression,presenceorabsenceofcalfhypertrophy,highserumlevelsofCK,andpatternofinheritance.LaboratoryDiagnosisEMGmusclebiopsyDNAanalysisSerumCKECGDuchenneMuscularDystrophyX-linkedrecessivetrait.Femalecarrythegenearecarriers.incidenceis1in3,500malebirth

33、s.nogeographic,ethnicvariation.onethirdarenewmutations;lifespanofDMDisshortened,about20-30y.prevalenceisless(1to18,000males).ClinicalFeatures1.Evident at birth if serum enzymes aremeasured.2.Thesymptomsdonotbeginuntilage3to5 years,but that may be a measure ininfants.3.Walkingdelayedandtheboysneverru

34、nnormally;Soon toe-walking and waddinggait.4.Progresses,overt difficulty walking,climbingstairs,andrisingfromchairs.5.An exaggerated lordosis is assumed tobalance.6.Theboystendtofalleasily,andtheyhavedifficultyrisingfromtheground.(Gowerssign)7.Asthediseaseprogresses:thearmsandhandsareaffectedswallow

35、ing,ocularmovementsaresparedIliotibialcontractureslimithipflexionheelcordcontracturescausetoe-walking8.Atage9-12,theboynolongerwalksandenters a wheelchair;scoliosis may becomeserious;contributetodisability.9.Byaboutage20,respirationiscompromised and mechanical ventilation isneeded.10.heartissparedcl

36、inically,butECGisabnormal:increasedR-Samplitude,anddeep,narrowQwaves.congestivefailuremaysuperveneinafewcases.gastrointestinalsystemissparedbutacutegastricdilatationinafewcases.MentalretardationaffectaboutonethirdofboyswithDMD.BeckerMuscularDystrophy(BMD)resemblesDMDinessentialcharacteristics:X-link

37、ed,calf hypertrophy,weakness isgreatestproximally,andserumCKlevelsarehigh.EMGandmusclehistologyaresame.Thetwodifferenceareageatonset(usuallyafterage12)andrateofprogression(stillwalkingafterage20,oftenlater).Diagnosis1.The clinical diagnosis of DMD is evident fromclinicalfeatures.In sporadic,atypical

38、 cases,spinal muscularatrophy might be mistake for DMD fasciculationand EMG denervation,identify the neurogenicdisorder.2.SerumCKlevelofDMDandBMDareusuallyatleast20timesnormal3.Dystrophingeneandproteinanalysiscanmakethecorrectdiagnosis.TreatmentThere is no specific drug therapy for DMDandBMD.Prednis

39、onetherapywasbetterthanplaceboincontrolledtrials.Bracingmaypreventscoliosisinwheelchair-boundpatients.Surgical correction of spinal and limbdeformitiestomaintainambulationaslongaspossible.Facioscapulohumeral(FSH)MuscularDystrophyautosomaldominantfashion.characteristicdistributionofweakness:thefaceis

40、alwaysaffected.Progressionisslow;evenbeasymptomatic.Onsetinadolesence,occasionallydetectedinchildren.Serumenzymelevelsarenormal.FSHDgenemapsto4q35-qter.ClinicalManifestations1.Facialweakness,Patientshaveneverbeenabletowhistleorblowupaballoon.2.Scapularwingingisprominent.3.The shoulder girdle has a c

41、haracteristicappearance.cannotraisethearmslaterallytoshoulderlevel.4.Weaknessinthelegsmayaffectproximalmuscles.Laboratorystudies:EMG and muscle biopsy show amyopathicpattern.Thehistologicchangesaremild.Serumenzymevaluesareusuallynormalortriviallyelevated.ECGisnormal.Diagnosis:Accordingtotheclinicalf

42、eatures,autosomaldominantfashion,serumCKlevel,andEMG.Management:Treatmentissymptomatic.Limb-GirdleMuscularDystrophy(LGMD)LGMDisamyopathicsyndromesofproximallimbweaknessthatareusuallyslowlyprogressive.Clinicalmanifestations1.Onsetinadolescenceoradult,andinheritance:autosomaldominantorrecessive.2.The

43、legs are usually affected first,withdifficultyclimbingstairsandrisingfromchairs.3.Awaddinggait.risingthearmsdifficult,andwingingofthescapula4.Kneejerkstendtolostbeforetheanklejerks.Cranial muscles are usually spared.Progressionisslow.5.EMGandmusclebiopsyshowmyopathicchanges.SerumCKmaybeelevatedbutlesssothaninDMD.Diagnosis:According to the clinical features andexclusiontoincludesyndromesthatdidnotmeetcriteriaforDMD,FSHD,ormyotoniccategorise.Management:Treatmentissymptomatic.同学们来学校和回家的路上要注意安全同学们来学校和回家的路上要注意安全