流行性乙型脑炎的教育课件PPT-(1).ppt 48页

'EpidemicEncephalitisB CasereportHistorytaking：Aboy,4yearsold，borninthecountryside.Feverlastfor4days，convulsionandconfusionlastabout6hours.Physicalexamination：T40.5℃，R30bpm，P120bpm，BP100/60mmHg.Unconsciousness,conjunctivaledema,lungscanbeheardwheezes.Musclehypertonia,kneehyperreflexia,Babinskisign(+)Otherhistory?Accessoryexamination? AbstractJapaneseencephalitis(JE),anacuteinfectiousdiseasecausedbythemosquito-borneJapaneseencephalitisvirus(JEV)andfeaturedasinflammationinbrainparenchyma.Fever,confusion,coma,convulsion,pathologicalreflexandmeningealirritation.Respiratoryfailureinseverecases,highmortality,and10%resultinpermanentneuropsychiatricsequelea. EtiologyAsinglestrandedRNA,40-50nm,11kilobasesgenomes.RNAgenomeispackagedinthecapsidproteinformingthecoreofthevirus.Thegenomesalsoencodesseveralnonstructuralproteins(NS1,NS2a,NS3,NS4a,NS4b,andNS5)JEVcanbekilledbydisinfectant,100℃2minutesor56℃30minutes EtiologyAntigenicstability,infectioncanproducecomplement-bindingantibodies,neutralizingantibodiesandhemagglutinationinhibitionantibodies,contributetoclinicaldiagnosisandepidemiologicalinvestigation EpidemiologySourcesofinfection:JEisazoonosis,mosquitoesbecomeinfectedbyfeedingdomesticpigsandwildbirdsinfectedwiththeJEV.JEVisamplifiedinthebloodsystemsofthedomesticpigsandwildbirds.Pigsaretheimprotantamplifiedandreservoirs.Otherreserviorincludescow,sheep,horse,duck,gooseandchicken. EpidemiologyRouteoftransmission:thebiteofaninfectedmosquito,primarilyCulexspecies.Humansareadead-endhostintheJEVtramsmissioncycle.JEVisnottransmittedfromperson-to-person.OnlydomesticpigsandwildbirdsarecarriersoftheJEV. Epidemiology.Susceptiblepopulation:Generallysusceptible,especiallyresidentsofruralareasinendemiclocation,mostlyasymptomatic.Theratioofpatientsandlatentinfectionwas1:1000-2000.Pre-existingantibodies.CountriesthatstillhaveperiodicepidemicsincludeIndia,Cambodia,Nepalandsoon. Epidemiology.Epidemicfeature:mostcasesintemperateandsubtropicalareasoccurfromJunetoSeptember,whileintropicalareasoccurthroughouttheyear.Fivegenotypes:genotypesI,II,III,IV,V.GenotypesIandIIIoccurprincipallyintemperate,epidemicareas,andgenotypeIIandIVoccurprincipallyintropical,endemicregions. PathogenesisandPathologyJEVMononuclearmacrophagesmultiplyviremiaInvadetheCNSNotinvadetheCNSIncidenceLatentinfection ThissectionofbrainwastakenfromapatientwithJapaneseencephalitis,andshowsthegrosspathologyfoundinallofthearbovirusencephalitides.Thechanges,whichconsistofperivascularcongestionandhemorrhage,maybediffuseorfocal,buttheyareseenpredominantlyincorticalgrayanddeepgraymatter PathogenesisandPathologyJEVDirectinvasionAntigen-antibodybindingtotheimmuneattackNervecelllesionsVascularsheathformationThalamus,basalganglia,brainstem,cerebellum,hippocampus,cerebralcortexGlialcellproliferation Showsofteninglesions,oval-shapedlightpalearea,thestructurewasloosemesh ClinicalmanifestationsIncubationperiodof5-15days.thevastmajorityofinfectionsareasymptomatic,only1in250infectionsdevelopintoencephalitis.Typicalmanifestation:therearefourstagesTheprimarystage(1-3days):onsetwassuddenwithhighfever,upto39-41℃in1-2daysaccompaniedheadacheandmalaise.Anorexia,nausea,orabdominalpain.Apathyandneckrigidity. ClinicalmanifestationsTheproximitystage(fourthtotenthdays)HyperthermiaConsciousdisturbanceConvulsionRespiratoryfailureOthernervoussymptomsandsignsCirculationfailure ClinicalmanifestationsTheproximitystage：Hyperthermia:acuteonset;morethan40℃,lasts7-10daysgenerallyandsomegravecasescanlastfor3weeks.Thehighertemperature,thelongercourse,themoreseriousofJE. ClinicalmanifestationsTheproximitystageConsciousdisturbance：Lethargy,delirium,coma,anddisorientationaremainpresentationsAppearsmostlyatthe3-8days,lastingforalmost1weekApositivecorralationbetweentheseriousandthelastingtimeofcomaandthegravityofJEandprognosis ClinicalmanifestationsTheproximitystageConvulsion：Causes:highfever,cerebraledema,brainparenchymalinflammationOneormorefocal/asymmetricsignsappearinginthefirstfewdaysLight:theface,lips,localconvulsions,severecasesofthebodyAbout30%ofsurvivorshavefrankpersistentmotorlanguageimpairment. ClinicalmanifestationsRespiratoryfailure:causedbyinflammatoryofbrainparenchyma,hypoxia,cerebraledema,acuteintracranialhypertensionandcerebralherniaCerebralhenia：Spittingvomiting,convulsionsComaincreasedPupilchanges.Anteriorfontanelbulging,papilledema ClinicalmanifestationsTheproximitystage：Circulationfailure:rarely,tachycardia,hyperorhypotensionandrarelyECGevidenceofpericarditis.Othernervoussymptomsandsigns:superficialreflexdisappearsorweakens;deepreflexaccentuationsfirstandthedisappearsandtherearesymptomsandmeningealirritation. ClinicalmanifestationshyperthermiaconvulsionRespiratoryfailureArecriticalpresentationsofJEandrespiratoryfailureistheleadingcauseofdeath ClinicalmanifestationsTheconvalescencestage：DefervescenceoffeverandneurologicimprovementItusuallylastsforatleasttwoweeks ClinicalmanifestationsThesequelaestage：theexistenceofneuropsychiatricsymptomsafter6months。Theincidenceofabout5%to20%. AxialT2weighted(TR/TE=2500/90)image.(A)Hyperintenselesionsatbilateralthalami(arrows)wereshownonthe14thdaysafteronset.(B)Smallhyperintenselesionsatbilateralthalami(arrows)onthe60thdayafteronsetClinicalmanifestations LaboratoryexaminationsWhitebloodcell:growsupto10~20×109/L,neutrophiloccupiedmorethan80%.SomepatientshavenormalWBCcounts.Cerebrospinalfluid(CSF)：lumbarpuncturetoobtainCSFsamples. LaboratoryexaminationsCerebrospinalfluid(CSF)：Theopeningpressureisusuallynormalbutmayberaised.Mononuclearwhitebloodcellsmaybe50~500×106/L;Glucoselevelsarenormal;Proteinlevelsaremildlyelevatedinmostcases,oftenlessthan900mg/dl LaboratoryexaminationsAntibobydetection:SpecificIgMantibodiesisthestandarddiagnostictestforJE,nearly100%sensitivity;IgMantibodylevelsmaybefoundevenwithin7daysofsymptoms.False-negativeresultsmayoccurifthesamplesaretestdtooearly.Somecross-reactivitymayarisefromotherflavivirusesandfromJEandyellowfevervaccinations LaboratoryexaminationsNucleicaciddetection:detectionofviralgenomebyRT-PCRiseasiertoperformandhighlyreliablewith100%sensitivity,JEVhasbeenisolateduptoevenalmost4monthsafterclinicalsymptomshavebegunInmagingstudies:MRIandCT DiagnosisEpidemiologydata:rigorousseasonality:summerandautumn;lessthan10yearsoldaremoresusceptiblebutmoreadultpatientsareseennowClinicalfeatures：acuteonsetheadache,vomitting,hyperthermia,convulsionandpositivepathologicreflexandmeningealirritationsign DiagnosisLaboratoryexaminations：peripheralbloodpicture,CSF,serumantibodies,EEG,CTandMRI,brainbiopsyVirologicalinvestigation:JEVisdifficulttobeseparatedfrombloodandCSF.JEVantigencanbedetectedinsuchbodyfluidusingPCR. DifferentialdiagnosisToxicbacillarydysenteryTuberculousmeningitisPurulentmeningitisEncephalitisbOnsetAcute，24hourpeakChronic,longcourse1-2peak1-2peakSeasonSummertoautumnNon-seasonalwinterandspringSummertoautumnCSFNormalChlorideandglucosearelow,highprotein,cellcount50*106/LChlorideandglucosearelow,highprotein,cellcount1000*106/LChlorideandglucosearenormal,highprotein,cellcount50~500*106/LPathogenAnusdrysmearofpuscells,bloodculturesofShigellaCSFfilmsmearTBCSFsmearstainingbacteriaCSFbacterialtestingwasnegative.SpecificIgMantibodies TreatmentGeneraltreatmentSymptomatictreatmenthyperthermia,convulsion,respiratoryfailure TreatmentGeneraltreatmentComapatientsshouldpayattention：OralcleaningPreventsecondarybacterialinfectionPreventbedsoresoccurProtectthecorneaAnti-fallingbedpreventthetonguebittenNotethatwater,electrolytes,acid-basebalance,butnottoomuchinfusionvolumetopreventbrainedema Treatmenthyperthermia：LowertheroomtemperaturePhysicalcooling:iceoralcoholcoolsalineWithconvulsions:hibernationtherapy(chlorpromazine+promethazine) Treatmentconvulsion：Cerebraledema:dehydration,20%mannitol1-2g/Kg,intravenousinfusion,4-6htime,whilecombinedwithadrenalcortexhormones,furosemide,50%GS,toreducevascularpermeability,PreventionofbrainedemaanddehydrationagentreboundapplicationRespiratoryblockage:suction,oxygen,ifnecessary,tracheotomy TreatmentRespriatoryfailure：Brainedema:dehydratingagentCentralrespiratoryfailure:availablerespiratorystimulantsImprovemicrocirculation,reducecerebraledema:vasodilators TreatmentRespriatoryfailure：RespiratorysecretionsInfarct:suction,atomizationinhalationofα-chymotrypsin;withbronchospasmmaybe0.25%-0.5%isoproterenolinhalation.Andappropriatetreatmentwithantibioticssuchasbacterialinfection.Ifnecessary,endotrachealintubationorincision,artificialrespirationventilation TreatmentRecoveryandsequelaeoftreatment:acupuncture,physicaltherapy,hyperbaricoxygentherapy prognosisControlthesourceofinfection:VaccinethepigsbeforetheepidemicseasonCutoffthetransmission:anti-mosquito,mosquitocontrol.Protectionofsusceptiblepopulations,vaccinationinjections prognosisVaccinationinjections:thecurrentdosingscheduleforpatientsaged3yearsorolderis1mlsubcutaneouslyondays0,7,and30(0.5mlinpatientsaged1-2y).Administerthelastdoseofvaccineatleast10dayspriortotravelinanendemicarea.Adversereactionsincludelocalpainandredness,fever,gastrointestinalsymptoms,headache CasereportHistorytaking：Aboy,4yearsold，borninthecountryside.Feverlastfor4days，convulsionandconfusionlastabout6hours.Physicalexamination：T40.5℃，R30bpm，P120bpm，BP100/60mmHg.Unconsciousness,conjunctivaledema,lungscanbeheardwheezes.Musclehypertonia,kneehyperreflexia,Babinskisign(+)Otherhistory?Accessoryexamination? CasereportOtherhistoryBeforethediseasewithorwithoutdiarrhea,cough,woundinfectionWithorwithouthistoryofchronicfeverandcoughHistoryofvaccinationThelivingenvironmentWithorwithoutsimilarpatients CasereportTakeintoaccountthesupplementaryexaminationsWBCanalysisConventionalstoolCSFBloodculture CasereportFurtherhistoryHeadache,projectilevomitingatearlyonsetHealth,historyofvaccinationisunknownSlaughterpiglocalfree-range,mosquitoismore.Therecentlocalsimilarpatients.Auxiliaryexamination：WBC15×109/L，N82％。Conventionalstoolisnormal。CSF：WBC62×106/LDignosis?Treatment？ CasereportDignosis:JEVTreatment：Generaltreatment:oxygen.Infusionsupplementwater,electrolytes,vitamins.ChooseantimicrobialstopreventrespiratorytractinfectionControltemperatureKeeprespiratorytractunobstructed:Timingsputumsuction,rollover,takebackRelievecerebraledema:mannitol+50%glucosealternatingintravenous Thankyou！'