中樞神經(jīng)系統(tǒng)感染(2)ppt課件.ppt

VIRALMENINGITIS ENCEPHALITIS Viralmeningitisreferstomeningitiscausedbyaviralinfection Childrenandyoungadultsarefrequentlyaffected Viralmeningitisismostoftencausedbyenteric腸道的virusesViralencephalitisbychildhoodexanthems皮疹 arthropod borne節(jié)肢動物agents蟲媒性病原體 andherpessimplextype1 Cause 最常見柯薩奇病毒ECHO病毒腸道病毒 其次流行性腮腺炎單純皰疹病毒腺病毒 Pathology Viralinfectionscanaffectthecentralnervoussysteminthreeways血源性播散 hematogenousdisseminationofasystemicviralinfection eg arthropod borneviruses蟲媒性病毒 軸突傳播 neuronalspreadofthevirusbyaxonaltransport eg herpessimplex rabies狂犬病病毒 自身免疫性感染后脫髓鞘 autoimmunepostinfectionsdemyelination脫髓鞘 eg varicella水痘病毒 influenza Pathologicchangesinviralmeningitisconsistofaninflammatorymeningealreactionmediatedbylymphocytes 病毒性腦膜炎的病理改變是由淋巴細(xì)胞介導(dǎo)的炎性腦膜反應(yīng) Encephalitisischaracterizedbyperivascularcuffing lymphocyticinfiltration andmicroglialproliferationmainlyinvolvingsubcorticalgraymatterregions Internuclearorintracytoplasmicinclusionsareoftenseen 病毒性腦炎的病理改變特點是血管周圍套袖樣改變 淋巴細(xì)胞浸潤 以及累及皮層下灰質(zhì)的小膠質(zhì)增生 并經(jīng)?？梢姷胶藵{或細(xì)胞漿內(nèi)包涵體 Clinicalfindings symptomsandsigns Clinicalmanifestationsincludefever headache neckstiffness photophobia畏光 painwitheyemovement andmildimpairmentofconsciousness Patientsusuallydonotappearasillasthosewithbacterialmeningitis Systemicviralinfectionmaycauseskinrash pharyngitis咽炎 lymphadenopathy淋巴結(jié)病 pleuritis胸膜炎 carditis心肌炎 jaundice黃疸 organomegaly器官腫大 diarrhea腹瀉 ororchitis睪丸炎 andthesefindingsmaysuggestaparticularetiologicagent病原體 Becauseviralencephalitisinvolvesthebraindirectly markedalterationsofconsciousness seizures andfocalneurologicsignscanoccur Whensignsofmeningealirritation腦膜刺激征andbraindysfunctioncoexist共存 theconditionistermedmeningoencephalitis腦膜腦炎 Laboratoryfindings CSFanalysisisthemostimportantlaboratorytest CSFpressureisnormalorincreasedalymphocyticormonocyticpleocytosis腦脊液細(xì)胞數(shù)增多ispresent withcellcountsusuallylessthan1000 ml highercountscanbeseeninlymphocyticchoriomeningitis脈絡(luò)叢腦膜炎orherpessimplexencephalitis Apolymorphonuclear多形核白細(xì)胞pleocytosiscanoccurearlyinviralmeningitis whileredbloodcellsmaybeseenwithherpessimplexencephalitis Proteinisnormalorslightlyincreased usually80 120mg dL Glucoseisusuallynormal butmaybedecreasedinmumps腮腺炎 herpeszoster帶狀皰疹 orherpessimplexencephalitis Gram sstainandbacterial fungal andacid fastbacillius AFB culturesarenegative Oligoclonalbands寡克隆區(qū)帶andCSFproteinelectrophoresis電泳abnormalitiesmaybepresent Anetiologicdiagnosiscanoftenbemadebyvirusisolation polymerasechainreaction oracute andconvalescentphase恢復(fù)期CSFantibodytiters抗體滴度 Bloodcountsmayshowanormalwhitecellcount leukopenia白血球減少癥 ormildleukocytosis白細(xì)胞增多 Serumamylase血清淀粉酶isfrequentlyelevatedinmumps腮腺炎 abnormalliverfunctiontestsareassociatedwithbothhepatitisviruses肝炎病毒andinfectiousmononucleosis單核細(xì)胞增多癥 TheEEGisdiffuselyslow especiallyifthereisdirectcerebralinvolvement Diagnosis Differentialdiagnosis Thedifferentialdiagnosisofmeningitiswithmononuclearcellpleocytosisincludespartiallytreatedbacterialmeningitis治療不徹底的細(xì)菌性腦膜炎aswellassyphilitic梅毒的 tuberculous結(jié)核性的 fungal parasitic寄生物的 neoplastic腫瘤的 andothermeningitides腦 脊 膜炎 EvidenceofsystemicviralinfectionandCSFwetmounts stainedsmears cultures andcytologicexamination細(xì)胞學(xué)檢查candistinguishamongthesepossibilities Whenpresumedearlyviralmeningitisisassociatedwithapolymorphonuclear多形核白細(xì)胞pleocytosisoflessthan1000whitebloodcells mLandnormalCSFglucose oneoftwostrategiescanbeused ThepaitentcanbetreatedforbacterialmeningitisuntiltheresultsofCSFculturesareknown Treatmentcanbewithheldandlumbarpuncture腰椎穿刺術(shù)repeatedin6 12hours Ifthemeningitisisviralinorigin thesecondsampleshouldshowamononuclearcellpleocytosis Adisorderthatmaybeclinicallyindistinguishablefromviralencephalitisistheimmune mediatedencephalomyelitisthatmayfollowviralinfectionssuchasinfluenza measles麻疹 orchickenpox水痘 Progressiveneurologicdisfunctiontypicallybeginsafewdaysaftertheviralillness butcanalsooccureithersimultaneously同時發(fā)生oruptoseveralweekslater Neurologicabnormalitiesresultfromperivenous靜脈周圍的demyelination脫髓鞘 withoftenseverelyaffectsthebrainstem TheCSFshowsalymphocyticpleocytosis腦脊液細(xì)胞數(shù)增多 usuallywithcellcountsof50 150 mL andmildproteinelevation Treatment Exceptforherpessimplexencephalitis whichisdiscussedseparatelynospecifictherapyforviralmeningitisandencephalitisisavailable Corticosteroidsareofnoprovenbenefitexceptinimmune mediatedpostinfectioussyndromes Headacheandfevercanbetreatedwithacetaminophen醋氨酚 butaspirinshouldbeavoided especiallyinchildrenandyoungadults becauseofitsassociationwithReye ssyndrome Seizuresusuallyrespondtophenytoin苯妥英鈉orphenobarbital苯巴比妥 Supportivemeasuresincomatose昏睡的patientsincludemechanicalventilationandintravenousornasogastricfeeding鼻飼 Prognosis Symptomsofviralmeningitisusuallyresolvespontaneouslywithin2weeksregardlessofthecausativeagent althoughresidualdeficits后遺癥maybeseen Theoutcomeofviralencephalitisvarieswiththespecificvirus forexample herpessimplexvirusinfectionsareassociatedwithseveremorbidityandhighmortalityrates Mortalityratesashighas20 havealsobeenreportedinimmune mediatedencephalomyelitis腦脊髓炎followingmeasles麻疹infections Herpessimplexvirus HSV encephalitis HSVisthemostcommoncauseofsporadic散發(fā)的fatalencephalitisintheUnitedStates Abouttwo thirdsofcasespatientsover40yearsofage Primaryherpesinfectionsmostoftenpresentasstomatitis口炎 HSVtype1 oravenereally性交的transmittedgenital生殖器eruption出疹 HSVtpye2 Thevirusmigratesalongnerveaxons軸突tosensoryganglia神經(jīng)節(jié) whereitpersistsinalatentformandmaybesubsequentlyreactivated ItisnotclearwhetherHSVtype1encephalitis themostcommontypeinadults representsaprimaryinfectionorareactivationoflatentinfection Neonatal新生兒的HSVencephaltisusuallyresultsfromacquisition獲得oftype2virusduringpassagethroughthebrithcanalofamotherwithactivegenital生殖器的lesions CentralnervoussysteminvolvementbyHSVtype2inadultsusuallycausesmeningitis ratherthanencephalitis Pathology HSVtpye1encephalitisisanacute necrotizing引壞死的 asymmetric不對稱的hemorrhagic出血性的processwithlymphocyticandplasmacell漿細(xì)胞reaction Usuallyinvolvesthemedialtemporalandinferiorfrontallobes Intranuclearinclusions核內(nèi)包涵體maybeseeninneurons神經(jīng)元andglia神經(jīng)膠質(zhì) Patientswhorecover康復(fù)期mayshowcystic囊的necrosis壞死oftheinvolvedregions 32 可編輯 嗜酸性CowdryA型包涵體 ClinicalFinding ASymptomsandSigns Theclinicalsyndromemayincludeheadache stiffneck vomiting behavioraldisorders memoryloss anosmia嗅覺喪失 aphasia hemiparesis輕偏癱 andfocalorgeneralizedseizures Activeherpeslabialis唇皰疹isseenoccasionally butdoesnotreliablyimplicateHSVasthecauseofencephalitis HSVencephalitisisuauallyrapidlyprogressiveoverseveraldaysandmayresultincomaordeath Themostcommonsequelae后遺癥inpatientswhosurvivearememoryandbehaviordisturbances reflectingthepredilection嗜好 偏愛ofHSVforlimbicstructures LaboratoryFindings LaboratoryFindings CSF TheCSFinHSVtpye1encephalitismostoftenshowsincreasedpressurelymphocyticormixedlymphocyticandpolymorphonuclear多形核白細(xì)胞pleocytosis 50 100whitebloodcells mL mildproteinelevation andnormalglucose Redbloodcells xanthochromia黃變 anddecreasedglucoseareseeninsomecases LaboratoryFindings VIRUS ThevirusgenerallycannotbeisolatedfromtheCSF butviralDNAhasbeendetectedbythepolymerasechainreaction聚合酶鏈反應(yīng)insomecases HSV抗體檢定 ELASA是現(xiàn)今國際上通用的HSV抗體檢測方法 本方法采用雙份血清和雙份腦脊液作HSV 1抗體的動態(tài)檢測 診斷標(biāo)準(zhǔn) 雙份CSF抗體有增高趨勢 滴度1 8以上 雙份CSF抗體4倍以上升高 血與CSF的抗體比值 40 LaboratoryFindings EEG TheEEGmayshowperiodic周期的slow wavecomplexesarisingfromoneorbothtemporallobes LaboratoryFindings CTMRI CTscansandMRImayshowabnormalitiesinoneorbothtemporallobes Thesecanextendtofrontalorparietalregions頂區(qū)andaresometimesenhancedwiththeinfusion注入ofcontrastmaterial造影劑 However imagingstudiesmayalsobenormal Diagnosis DifferentialDiagnosis Thesymptomsandsignsarenotspecificforherpesvirusinfection ThegreatestdiagnosticdifficultyisdistinguishingbetweenHSVencephalitisandbrainabscess腦膿腫 andthetowdisordersoftencannotbedifferentiatedonclinicalgroundsalone brainabscess brainabscess OtherCNSinfectionsandvasculitis血管炎canalsomimicHSVencephalitis Deginitivediagnosiscanbemadebybiopsyofaffectedbrainareas withthechoiceofbiopsysiteguidedbytheEEG CT orMRIfindings However becausetreatmentismosteffectivewhenbegunearlyandiscomparativelysafe themostcommonapproachistotreatpatientswithpossibleHSVencephalitisasdescribedbelowandtoreservebiopsyforthosewhofailtoimprove Treatment Themosteffe