小儿腹泻(英文).ppt

1,INFANTILEDIARRHEA,CHCUMSDIVISIONOFINFECTIOUSDISEASEANDGASTROENTEROLOGY,INFANTILEDIARRHEA,2,Background,Diarrheaisaclinicalsyndromeofdiverseetiologyassociatedwithmanyinfluencingfactors.Itisthemostfrequentchildhooddiseasesecondonlytotherespiratoryinfection.Themajorcauseofdeathamongworldschildrenandthenumberonekillerofchildrenunderfiveinmanydevelopingcountries.,3,DiseaseBurden,Worldwide3-5billionepisodes/year4-5milliondeaths/yearChildrenarethepredominantpopulations.3.2billionepisodes/yearin5ychildren1.3milliondeaths/yearin5ychildrenInChina836millionepisodesofdiarrheaeveryyear1/4-1/3ofalloutdoorpatientsandalargeamountofhospitalizationsofchildrenareduetodiarrhea,4,FluidityVolumeNumber,Inpediatrics,diarrheaisdefinedasanincreaseinthe,relativetotheusualhabitsofeachindividual,ofstools,Definition,5,NormalStoolofChildren,Breastfedbabies:passstools3-4timesadayyellowloose(softtorunny)buttexturedsweet-smellingBottlefedbabies:onceadaypaleyelloworyellowish-brownbulkierandmoreformedprettypungentBabiesonsolids:thickenanddarkenslightlyhaveastrongerodor,6,DehydrationMalnutrition,Mortality,Whydiarrheaismoredangerousforchildren?,7,MalnutritionandChildMortality,8,If:Diarrhea+Malnutrition,TheRISKofDEATHis4foldhigherthanthatofwellnourishedchildren,9,Whychildrenarehighlyvulnerabletodiarrhea?,ImmaturedigestivesystemMorenutritiondemandWeaknessofdefensesystemThenormalintestinalflorahavenotbuiltupwellBottlefeeding,10,EtiologyofDiarrhea,11,EtiologyofDiarrhea,Infective,Noninfective,VirusesBacteriaParasitesFungi,AllergicSymptomaticInappropriatefeedingFoodintoleranceClimate,12,ViralEnteropathogens,Viralenteropathogenscausemostillnessesinpediatricpopulation.,Rotavirus(mornthan50%acutediarrhea)AstrovirusNorwalkvirusCoronavirusCalicivirusEntericadenovirus(serotypes40and41),13,Rotavirus,14,Themostcommoncauseofchildhooddiarrheasecondonlytotheviralenteropathogens,EscherichiacoliEPEC;ETEC;EITC;EHEC;EAECCampylobacterjejuniShigellaspeciesSalmonellatyphimuriumYersiniaenterocoliticaStaphylococcusaureusClostridiumdifficileVibriocholerae,BacterialEnteropathogens,15,Rareetiologicpathogenofdiarrhea,CryptosporidiumparvumEntamoebahistolyticGiardialamblia,ParasitesPathogens,16,Rareetiologicpathogenofdiarrhea,CandidaalbicansAspergillusMucor,FungousPathogens,17,Themostimportantinfectivecausesofacutediarrheaindevelopingcountriesinchildrenare:,RotavirusEnterotoxigenicescherichiacoliShigellaCampylobacterjejuniSalmonellatyphimurium,18,EtiologyofDiarrhea,Infective,Noninfective,VirusesBacteriaParasitesFungi,AllergicSymptomaticInappropriatefeedinglactoseintoleranceClimate,19,OverfeedingIndigestibledietSuddenchangeofformulaInappropriatefeedingforamilk-fedbabyshiftingintosolidfood(toomuch,tooearly,toorapid),DietaryDiarrhea,Inappropriatefeeding:,20,AllergicDiarrhea,Primaryfoodhypersensitivity:3monthsafterbirth,Secondfoodhypersensitivity:Infectioninjuryandhyperpermeabilityofintestinalmucosalargemolecularproteinenteringbloodstreamallergicstate,CowsmilkproteinSoybeanproteinEggwhitepeanuts,meat,andfishetc.,21,SymptomaticDiarrhea,Diarrheaisonlyoneofthesymptomsofprimarydisease.Problemisnotoriginallylocatedinintestinaltract.RespiratorytractinfectionOtitismediaSomeinfectiousdiseases,etc.Alwaysbemild,andrecoverwiththeprimarydiseasegettingbetterTheyoungerthechildren,themorechancetogetasymptomaticdiarrheaaccompaniedbyotherdiseases.,22,LackofDisaccharidase,LactoseIntolerancePrimaryDisaccharidaseDeficiencyisararedisease(congenitaldefectsofcarbohydratehydrolysis).SecondDiaccharidaseDeficiency:RotavirusinfectionInjurestheenterocytesofvilliTransientdisaccharidasedeficiencyMalabsorptionoflactoseinthemilkTypicallooseandwaterystools,23,ClimateSeasonalvariationaffectsthedigestivefunctionofsmallchildren:incidenceofdiarrheaishighestduringtheearlyraninyseasonColdweathercausesincreasingofenterokinesiaHotweathercausesdecreasingofdigestiveenzymeandmalfunctionofdigestivetract,24,PathophysiologicalMechanismsofDiarrhea,25,VirusDiarrhea-RotavirusEnterotoxigenicEnteritisETEC,VibrioCholeraeEntero-InvasiveOrganismsShigellaSpecies,EIECDietaryDiarrhea,PathophysiologicalMechanismsofDiarrhea,26,PathogenesisofVirusDiarrhea,VirusinvadestheabsorptiveenterocytesofvillibutsparescryptcellsThevirusesreplicatesandinfectedenterocytesaredestroyed,Rotavirus,27,PathogenesisofVirusDiarrhea,1-Infectedabsorptiveenterocytesarekilledcausingpatchyepithelialcelldestructionandvillousshortening2-Destroyedabsorptivecellsarerapidlyreplacedbycellsthatmigratefromthecrypts.Villibecomecoveredwithimmaturenon-absorptivesecretorycellshaving:-nobrushborder-nobrushborderenzymes,OsmoticDiarrhea,28,PathogenesisofVirusDiarrhea(OsmoticDiarrhea),Rotavirusesattachandreplicateinthematureenterocytesatthetipsofsmallintestinalvilli,Destroyvillustipcells,variabledegreesofvillusbluntingmononuclearinflammatoryinfiltrateinthelaminapropria,Impairmentofdigestivefunctionsdiscreasinghydrolysisofdisaccharides,Impairmentofabsorptivefunctionsthetransportofwaterandelectrolytesviaglucoseandaminoacidco-transporters,Animbalanceintheratioofintestinalfluidabsorptiontosecretion,Malabsorptionofcomplexcarbohydrates,particularlylactose,Otherthandegestedintomonosaccharide,lactosebelysisintoorganicacid,hyperosmosis,Waterystool,29,VirusDiarrhea-RotavirusEnterotoxigenicenteritisETEC,VibrioCholeraeEntero-InvasiveOrganismsShigellaSpecies,EIECDietarydiarrhea,PathophysiologicalMechanismsofDiarrhea,30,PathogenesisofEnterotoxigenicDiarrhea,Pathogens:Vibriocholerae(cholera)ETECStaphylococcusaureusClostridiumdifficile,31,enterotoxigenicorganisms,Ingestion,smallbowelmucosaandproliferate,activatescellularguanylatecyclase,Heat-stableenterotoxin,promotethenetsecretionofwaterandchloride,increasedintracellularconcentrationsofcAMP,activatescellularadenylcyclase,bindstoreceptorsofepithelialcells,Heat-labileenterotoxin,decreaseabsorptionofsodiumandchloridebyvillouscells,increasedintracellularconcentrationsofcGMP,Secretorydiarrhea,PathogenesisofEnterotoxigenicDiarrhea(SecretoryDiarrhea),32,PathogenesisofEnterotoxigenicDiarrhea(SecretoryDiarrhea),1-EnterotoxigenicBacteriasecreteEnterotoxins2-ToxinstimulatestheproductionofC-AMPIncreasedC-AMPleadsto:3-InhibitionofabsorptionofNaandClfromthecellsofvilli4-StimulationofsecretionofClfromcryptcells,1,2,3,4,1,2,3,4,33,PathogenesisofEnterotoxigenicDiarrhea(SecretoryDiarrhea),Themucosaisnotdestroyedduringthisprocess,34,Animbalanceintheratioofintestinalfluidabsorptiontosecretion,sowaterystoolmayoccurinclinicalobservation,PathogenesisofEnterotoxigenicDiarrhea(SecretoryDiarrhea),35,EnterotoxigenicDiarrhea,Clinicalfinding:Waterydiarrheaandvomitingdevelopafteranincubationperiodof6hr-5days(2-3days,average)Low-gradefeveroccursinsomechildrenProfuse,painless,waterydiarrhea,sometimeswithflecksofmucusbutnobloodFluidandelectrolytelosses,tachycardia,tachypnea,asunkenanteriorfontanel,progresstocirculatorycollapse,36,VirusDiarrhea-RotavirusEnterotoxigenicenteritisETEC,VibrioCholeraeEntero-InvasiveOrganismsShigellaSpecies,EIECDietarydiarrhea,PathophysiologicalMechanismsofDiarrhea,37,InvasiveDiarrhea,Entero-InvasiveOrganisms:ShigellaspeciesEIEC(enteroinvasiveE.coli)CampylobacterjejuniSalmonellatyphimuriumYersiniaenterocolitica,Thecentraleventinpathogenesisisinvasionofcolonicmucosa,38,PathogenesisofInvasiveDiarrhea,Invasiveenteropathogen,Ingestion,GutlumenColonandrectummucousmembraneproper,ExtensivedestructionoftheepitheliallayerInflammation:Hyperemia,swelling,heavyneutrophilinfiltration,inflammatoryexudate,Thedesquamation,ulceration,andformationofmicroabscessesinthecolonicmucosainhibitabsorptionofwaterstoolsthatarefrequentandscantyandthatcontainbloodinflammatorycellsandmucus,39,PathogenesisofInvasiveDiarrhea,40,InvasiveDiarrhea,Clinicalfinding:Stoolsthatarefrequentandscantyandthatcontainbloodinflammatorycells,andmucusStoolexamination:largeamountofWBC,puscell,andRBCDehydrationandelectrolytedisturbancesarelessfrequentbecauseoflesslossofdigestivefluid,41,VirusDiarrhea-RotavirusEnterotoxigenicenteritisETEC,VibrioCholeraeEntero-InvasiveOrganismsShigellaSpecies,EIECDietarydiarrhea,PathophysiologicalMechanismsofDiarrhea,42,PathogenesisofDietaryDiarrhea,Inappropriatediet,IrritatesthebowelPromotetheperistalsisWaterenteringthelumen,Decomposedproductamineslacticacidaceticacid,Aciditydecreasing,Givethechancetothebacteriawhichlivedinlowerpartofbowelcomingup,Endogenousinfection,Aggravatetheintestinalfunctiondisturbance,Indigestedfoodaccumulateintheupperpartofintestine,Dyspepsia,Indigestedfoodfermentandputrescence,Hyperosmosis,Diarrhea,43,MorphologyofIntestinalMucosa,44,MorphologyofIntestinalMucosa,Villicoveredmainly(90%)bytallcolumnarabsorptivecells(Enterocytes)havingamicrevillarbrushborder,CryptsoflieberkuhnCoveredmainlybyshortcolumnarsecretorycellsGobletcellswithoutbrushborder,45,DefenseBarriersoftheEnterocytes,1.Physicalbarrier:mucus2.Bacteriological(flora)3.Immunological:SecretoryIgA,1,2,3,46,NormalFlora,Breast-fed:AGram-positivepopulation:BifidobacteriaandLactobacilliBottle-fed:AGram-negativeflora:Enterobacteriaceae,47,ClinicalManifestations,48,Clinicalmanifestations,GastrointestinalsymptomSystemicsymptomDehydrationandelectrolytedisturbances,49,Assessmentofachildwithdehydration&electrolytedisturbances,50,Dehydration,Excessivelossofwater,especiallylossofextracellularfluid.,51,52,53,54,AssessmentofaDehydration,55,Typeofdehydration,56,serumpotassium3.5mmol/LEtiologyExcessiveoflossInsufficientintakeDistributionaldisturbanceofextracelluarandintracelluarpotassium,Hypopotassaemia,57,(二)低钾血症,Manifestations（1）lownervousandmuscularexcitabilitynervousexcitability：downcast,lethargymuscularexcitability：weakness、byporesalexiaoftendonjerk,paralysisGIsmoothmuscleexcitability：paralyticileus（2）cardiovascularsystem：cardiacdysrhythmia,lowheartsound,electrocardiographicabnormality,Hypopotassaemia,serumpotassium3.5mmol/L,58,serumcalcium1.88mmol/LHighnervousandmuscularexcitability,Hypocalcemia,59,1etiology(1)lossofalkalinesubstancefromGItrack(2)acidsubstanceaccumulationinbodyH+排除2manifestations:hyperpnoea、increasedheartrate、seriselip、consciousdisturbancefortheseverecases,H+产生,MetabolicAcidosis,60,ClassificationofDiarrheabasedon,SeverityDurationEtiology,61,ClassificationofDiarrhea,1.Milddiarrhea:Mostofthecasesarenon-infectiousdiarrheaFrequencyofstooloftenlessthan10times/dayYellowishloosestool,soursmellwithafewofmucusfatdropinmicroscopicexamGeneralconditionisgood,self-limitedonseveraldays2.Moderatediarrhea:3.Severediarrhea:Mostofthecasesareinfectiousdiarrhea(rotavirus,shigella)Frequencyofstooloftenmorethan10times/dayWaterystool,plentyofmucus.Generalconditionispoor,usuallyaccompanywithvomitingandfever,dehydrationandelectrolytedisturbance,62,Acutestage:thecourseofthediseaseslessthan2weeksPersistingtype:thecourseofdiseasemorethan2weeksbutlessthan2monthsChronicstage:thecourseofdiseasemorethan2months,ClassificationofDiarrhea,63,PersistingandChronicDiarrhea,Complicatereasons:Persistinginfection,Allergicstate,Lackofdisaccharidase,Immunodeficience,Broadspectrumantibioticusage,Malnutrition,Malabsorption,etc.PathogenesisisnotclearGreatdangerous:MalnutritionandgrowthretardationMortalityishighTroublesometobecontrolled:AdequatecaloriesReestablishthenormalflora,64,RotavirusesInfection,65,Rotavirusesinfection,History:Firstrecognizedinhumansin1973byAustralianScientistBishop,withahubbedwheelappearanceunderelectronmicroscope,givingtheirnameVirology:Double-strandedRNAvirusVP6:A-Ggroup,groupAisthemostimportantgroupinchildhoodinfection,66,Rotavirusesinfection,Peakseason:Deepfallandwinter(October-February）Causingsharplyincreasingofoutdoorpatientsinautumnandwinter,alsonamedautumndiarrheaPeakage:6m-2y,rarelyhappeninchildrenabove4yDiseaseburden:80%infectiousdiarrheainpediatricclinicinautumnandwinterAbout1/4to1/3(morethan800cases)hospitalizeddiarrheachildrenarecausedbyrotavirusinourwardeveryyear,67,Rotavirusesinfection,Clinicalmanifestations:Onsetofsuddenfever,respiratorytractsymptomsVomiting,wateryorsoftstoolthatlackgrossbloodormucusSeveredehydrationthaninfectionbyotherviralpathogensComplicationsandfatalitiesarerelatedalmostexclusivelytotheadverseeffectsofdehydration,electrolyteimbalance,andacidosisMalnutritionisariskfactorforsevereconsequencesDisaccharidesIntoleranceLaboratoryfindings:SpecificantigensinstoolspecimenrecommendedbyWHO,68,Diagnosis,69,Diarrhea?,Watery,loosestoolswithoutoronlyaminuteamountofWBC,EpidemicdataStoolcultureSerousassay,StoolcultureSerousassay,ShigellaspeciesEIECCampylobacterjejuniSalmonellatyphimuriumYersiniaenterocolitica,VirusDiarrheaETEC,EPEC,LotsofWBCandRBC,mucusinstools,Acutestage,Persistingorchronicdiarrhea,Antibioticassociatediarrhea,Infective,Non-infective,Allergicstate?Symptomaticdiarrhea?Inappropriatefeeding?foodintoleranceLackofdisaccharidase?Immunodeficience?Malnutrition?Malabsorption?etc.,Persistinginfection?,EntamoebahistolyticGiardialambliaCryptosporidium,StaphylococcusClostridiumdifficileCandidaalbicans,70,Treatment,71,Mainlinesofmanagement,FeedingFluidtherapyDrugs,72,1.Feedingduringdiarrhea,ContinuefeedingthechildGiveasmuchasthechildwantGivesmallfrequentfeedsEncourageanorexicchildtoeat,73,Forbreast-fed,Continuebreastfeedingasusualduringandafterdiarrheaandrehydrationtherapy.,1.Feedingduringdiarrhea,74,Forformula-fed,Lowlactoseoflactose-freeformulaonlyincaseoflactoseintolerancechildren(rotavirus),1.Feedingduringdiarrhea,75,ChildrenonMixedDietContinuenormalfeedingasusualGiverepeatedsmallfrequentfeedsAvoidtoosweetenedoroilyfoodsAvoidfoodscontainingahighfibercontent,1.Feedingduringdiarrhea,76,2.Fluidtherapy,77,3.DrugsinthemanagementofDiarrhea,78,Commonlyuseddrugsindiarrhea,AntimicrobialagentsAntiparasiticsProbiotics:lactobacilli,BifidobacteriaAntidiarrhealagents:adsorbantsandmucousmembraneprotectors:SMECTA,79,Antimicrobialagents,Antimicrobialagentsarenotrecommendedforviraldiarrheainvasivepathogenandtoxicpathogeninfectionshouldchooseeffectiveantimicrobialagentsantibioticsshouldbestoppedorchangedfortheantibioticassociatediarrhea,80,FunctionsofNormalFlora,DigestionProductionofvitaminsStimulationofhostimmuneresponseInhibitionofpathogenattachmentProductionofpathogeninhibitorysubstances,81,FluidTherapy,82,ORSTherapyinmildtomoderatedehydration,ORSisthepreferredtreatmentforfluidandelectrolytelossescausedbydiarrhoeainchildrenwhohavemildtomoderatedehydration50-100ml/kgORStobegivenovera4-hourperiodWHOrecommendedORSHighsodiumcontent90mmol/l,83,Intravenousfluidtherapy,Severelydehydratedorwhoareinastateofshockmustreceiveimmediateandaggressiveintravenousfluidtherapy,CompletecorrectingofthedeficitReplacingongoinglossofwaterandelectrolytesSupplythephysiologicalmaintenance,84,PhaseI:Treatshock(0-30minutes)PhaseII:InitialRehydration(-8hours)PhaseIII:ContinuedReplacement(8-24hours),10-20ml/kg0.9%NaCl,Reassess,Improved,NoChange,MeasureplasmaelectrolytesCalculatefluiddeficitandmaintenance,Reviewplasmaelectrolytesandfluidstatus,Initialreplacementwithsaline-dextrosesolutionHalfthecalculatedfluiddeficitplusmaintenance,Replacementwithsaline-dextrosesolutionHalfthecalculate