儿科英文课件化脓性脑膜炎Bacterial-meningitis.ppt

Introduction,Bacterialmeningitisisaninflammationoftheleptomenings,usuallycausingbybacterialinfection.Bacterialmeningitismaypresentacutely(symptomsevolvingrapidlyover1-24hours),subacutely(symptomsevolvingover1-7days),orchronically(symptomsevolvingovermorethan1week).,Introduction,Annualincidenceinthedevelopedcountriesisapproximately5-10per100000.30000infantsandchildrendevelopbacterialmeningitisinUnitedStateseachyear.Approximately90percentofcasesoccurinchildrenduringthefirst5yearsoflife.,Introduction,Casesunderage2yearsaccountforalmost75%ofallcasesandincidenceisthehighestinearlychildhoodatage6-12monthsthaninanyotherperiodoflife.Therearesignificantdifferenceintheincidenceofbacterialmeningitisbyseason.,Etiology,Causativeorganismsvarywithpatientage,withthreebacteriaaccountingforoverthree-quartersofallcases:Neisseriameningitidis(meningococcus)Haemophilusinfluenzae(ifveryyoungandunvaccinated)Streptococcuspneumoniae(pneumococcus),Etiology,OtherorganismsNeonatesandinfantsatage2-3monthsEscherichiacoliB-haemolyticstreptococciStaphylococcusaureusStaphylococcusepidermidisListeriamonocytogenes,Etiology,ElderlyandimmunocompromisedListeriamonocytogenesGramnegativebacteriaHospital-acquiredinfectionsKlebsiellaEscherichiacoliPseudomonasStaphylococcusaureus,Etiology,ThemostcommonorganismsNeonatesandinfantsundertheageof2monthsEscherichiacoliPseudomonasGroupBStreptococcusStaphylococcusaureus,Etiology,Childrenover2monthsHaemophilusinfluenzaetypebNeisseriameningitidisStreptococcuspneumoniaeChildrenover12yearsNeisseriameningitidisStreptococcuspneumoniae,Etiology,MajorroutesofleptomeninginfectionBacteriaaremainlyfromblood.Uncommonly,meningitisoccursbydirectextensionfromnearlyfocus(mastoiditis,sinusitis)orbydirectinvasion(dermoidsinustract,headtrauma,meningo-myelocele).,Pathogenesis,SusceptibilityofbacterialinfectiononCNSinthechildrenImmaturityofimmunesystemsNonspecificimmuneInsufficientbarrier(Blood-brainbarrier)InsufficientcomplementactivityInsufficientchemotaxisofneutrophilsInsufficientfunctionofmonocyte-macrophagesystemBloodlevelsofdiminishedinterferon(INF)-andinterleukin-8(IL-8),Pathogenesis,SusceptibilityofbacterialinfectiononCNSinthechildrenSpecificimmuneImmaturityofboththecellularandhumoralimmunesystemsInsufficientantibody-mediatedprotectionDiminishedimmunologicresponseBacterialvirulence,Pathogenesis,Aoffendingbacteriumfrombloodinvadestheleptomeninges.BacterialtoxicsandInflammatorymediatorsarereleased.BacterialtoxicsLipopolysaccharide,LPSTeichoicacidPeptidoglycanInflammatorymediatorsTumornecrosisfactor,TNFInterleukin-1,IL-1ProstaglandinE2,PGE2,Pathogenesis,Bacterialtoxicsandinflammatorymediatorscausesuppurativeinflammation.InflammatoryinfiltrationVascularpermeabilityalterTissueedemaBlood-brainbarrierdetroyThrombosis,Pathology,Diffusebacterialinfectionsinvolvetheleptomeninges,arachnoidmembraneandsuperficialcorticalstructures,andbrainparenchymaisalsoinflamed.Meningealexudateofvaryingthicknessisfound.Thereispurulentmaterialaroundveinsandvenoussinuses,overtheconvexityofthebrain,inthedepthsofthesulci,withinthebasalcisterns,andaroundthecerebellum,andspinalcordmaybeencasedinpus.Ventriculitis(purulentmaterialwithintheventricles)hasbeenobservedrepeatedlyinchildrenwhohavediedoftheirdisease.,Pathology,Invasionoftheventricularwallwithperivascularcollectionsofpurulentmaterial,lossofependymallining,andsubependymalgliosismaybenoted.Subduralempyemamayoccur.Hydrocephalusisancommoncomplicationofmeningitis.ObstructivehydrocephalusCommunicatinghydrocephalus,Pathology,Bloodvesselwallsmayinfiltratedbyinflammatorycells.EndothelialcellinjuryVesselstenosisSecondaryischemiaandinfarctionVentricledilatationwhichensuesmaybeassociatedwithnecrosisofcerebraltissueduetotheinflammatoryprocessitselfortoocclusionofcerebralveinsorarteries.,Pathology,Inflammatoryprocessmayresultincerebraledemaanddamageofthecerebralcortex.ConsciousdisturbanceConvulsionMotordisturbanceSensorydisturbanceMeningealirritationsignisfoundbecausethespinalnerverootisirritated.Cranialnervemaybedamaged,Clinicalmanifestation,Bacterialmeningitismaypresentacutely(symptomsevolvingrapidlyover1-24hours)inmostcases.Symptomsandsignsofupperrespiratoryorgastrointestinalinfectionarefoundbeforeseveraldayswhentheclnicalmanifestationsofbacterialmeningitishappen.SomepatientsmayaccesssuddenlywithshockandDIC.,Clinicalmanifestation,ToxicsymptomalloverthebodyHyperpyrexiaHeadachePhotophobiaPainfuleyemovementFatiguedandweakMalaise,myalgia,anorexia,Vomiting,diarrheaandabdominalpainCutaneousrashPetechiae,purpura,Clinicalmanifestation,ClinicalmanifestationofCNSIncreasedintracranialpressureHeadacheProjectilevomitingHypertensionBradycardiaBulgingfontanelCranialsuturesdiastasisComaDecerebraterigidityCerebralhernia,Clinicalmanifestation,ClinicalmanifestationofCNSSeizuresSeizuresoccurinabout20%-30%ofchildrenwithbacterialmeningitis.Seizuresisoftenfoundinhaemophilusinfluenzaeandpneumococalinfection.Seizuresiscorrelativewiththeinflammationofbrainparenchyma,cerbralinfarctionandelectrolytedisturbances.,第一课件网站,Clinicalmanifestation,ClinicalmanifestationofCNSConsciousdisturbanceDrowsinessCloudingofconsciousnessComaPsychiatricsymptomIrritationDysphoriadullness,Clinicalmanifestation,ClinicalmanifestationofCNSMeningealirritationsignNeckstiffnessPositiveKernigssignPositiveBrudzinskissign,Clinicalmanifestation,ClinicalmanifestationofCNSTransientorpermanentparalysisofcranialnervesandlimbsmaybenoted.Deafnessordisturbancesinvestibularfunctionarerelativelycommon.Involvementoftheopticnerve,withblindness,israre.Paralysisofthe6thcranialnerve,usuallytransient,isnotedfrequentlyearlyinthecourse.,Clinicalmanifestation,Symptomandsignsoftheinfantundertheageof3monthsInsomechildren,particularlyyounginfantsundertheageof3months,symptomandsignsofmeningealinflammationmaybeminimal.Feverisgenerallypresent,butitsabsenceorhypothermiainainfantwithmeningealinflammationiscommon.Onlyirritability,restlessness,dullness,vomiting,poorfeeding,cyanosis,dyspnea,jaundice,seizures,shockandcomamaybenoted.Bulgingfontanelmaybefound,butthereisnotmeningealirritationsign.,Complication,SubduraleffusionSubduraleffusionsoccurinabout10%-30%ofchildrenwithbacterialmeningitis.Subduraleffusionsappeartobemorefrequentinthechildrenundertheageof1yearandinhaemophilusinfluenzaeandpneumococalinfection.Clinicalmanifestationsareenlargementinheadcircumference,bulgingfontanel,cranialsuturesdiastasisandabnormaltransilluminationoftheskull.SubduraleffusionsmaybediagnosedbytheexaminationofCTorMRIandsubduralpricking.,Complication,EpendymitisNeonateorinfantwithmeningitisGram-negativebacterialinfectionClinicalmanifestationPersistenthyperpyrexia,FrequentconvulsionAcuterespiratoryfailureBulgingfontanelVentriculomegaly(CT)CerebrospinalfluidbyventricularpunctureWBC50109/LGlucoseo.4g/L,Complication,CerebullarhyponatremiaSyndremofinappropriatesecretionofantidiuretichormone(SIADH)HyponatremiaDegradeofbloodosmoticpressureAggravatedcerebraledemaFrequentconvulsionAggravatedconsciousdisturbance,Complication,HydrocephalusIncreasedintracranialpressureBulgingfontanelAugmentationofheadcircumferenceBrainfunctiondisorderOthercomplicationDeafnessorblindnessEpilepsyParalysisMentalretardationBehaviordisorder,LaboratoryFindings,PeripheralhemogramTotalWBCcount20109/L40109/LWBCDecreasedWBCcountatsevereinfectionLeukocytedifferentialcount80%90%Neutrophils,LaboratoryFindings,Routexaminationofcerebrospinalfluid(CSF)IncreasedpressureofcerebrospinalfluidCloudinessEvidentIncreasedtotalWBCcount(1000109/L)EvidentIncreasedneutrophilsinleukocytedifferentialcountEvidentDecreasedglucose(1.1mmol/l)EvidentIncreasedproteinlevelDecreasedornormalchloridateCSFfilmpreparationorcultivation:positiveresult,LaboratoryFindings,EspecialexaminationofCSFSpecificbacterialantigentestCountercurrentimmuno-electrophoresisLatexagglutinationImmunofluorescenttestNeisseriameningitidis(meningococcus)HaemophilusinfluenzaeStreptococcuspneumoniae(pneumococcus)GroupBstreptococcus,LaboratoryFindings,EspecialexaminationofCSFOthertestofCSFLDHLacticacidCRPTNFandIgNeuronspecificenolase(NSE),LaboratoryFindings,OtherbacterialtestBloodcultivationFilmpreparationofskinpetechiaeandpurpuraSecretioncultureoflocallesionImageologyexamination,Diagnosis,DiagnosticmethodsAcarefulevaluationofhistoryAcarefulevaluationofinfantssignsandsymptomsAcarefulevaluationofinformationonlongitudinalchangesinvitalsignsandlaboratoryindicatorsRoutexaminationofcerebrospinalfluid(CSF),Differentialdiagnosis,Clinicalmanifestationofbacterialmeningitisissimilartoclinicalmanifestationofviral,tuberculous,fungalandasepticmeningitis.Differentiationofthesedisordersdependsuponcarefulexaminationofcerebrospinalfluidobtainedbylumbarpunctureandadditionalimmunologic,roentgenographic,andisotopestudies.,CharacteristicsofCSFoncommondiseaseinCNS,TreatmentAntibioticTherapy,TherapeuticprincipleGoodpermeabilityforBlood-brainbarrierDrugcombinationIntravenousdripFulldosageFullcourseoftreatment,AntibioticTherapy,SelectionofantibioticNoCertainlyBacteriumCommunity-acquiredbacterialinfectionNosocomialinfectionacquiredinahospitalBroad-spectrumantibioticcoverageasnotedbelowChildrenunderage3monthsCefotaximeandampicillinCeftriaxoneandampicillin(childrenoverage1months)Childrenover3monthsCefotaximeorCeftriaxoneorampicillinandchloramphenicol,AntibioticTherapy,CertainlyBacteriumOncethepathogenhasbeenidentifiedandtheantibioticsensitivitiesdetermined,themostappropriatedrugsshouldselected.Nmeningitidis:penicillin,tert-cephalosporinSpneumoniae:penicillin,tert-cephalosporin,vancomycinHinfluenzae:ampicillin,tert-cephalosporinSaureus:penicillin,nefcillin,vancomycinEcoli:ampicillin,chloramphenicol,tert-cephalosporin,AntibioticTherapy,Courseoftreatment7daysformeningococcalinfection1014daysforHinfluenzaeorSpneumoniaeinfectionMoretha