兒科學教學課件：8 肺炎七年制-2013年-C

RespiratoryDisordersTopics

RespiratorydisordersRespiratoryinfectionsPneumoniaTopics

RespiratorydisordersRespiratoryinfectionsPneumonia

50%ofconsultationwithgeneralpractitionersoracuteillnessinyoungchildrenandathirdofconsultationsinolderchildren25-30%ofacutepediatricadmissionstohospital,someofwhicharelife-threatening

Acuterespiratorytract

infectionsformamajorpartofpediatricpracticeAsthma

isthemostcommonchronicillnessofchildhoodCysticfibrosisisthemostcommoninheriteddisorderinCaucasianscausingchronicdiseaseRespiratoryDisordersTopics

Respiratorydisorders

RespiratoryinfectionsPneumoniaRespiratoryInfections

Themostfrequentinfectionsofchildhood:6-8/yearPathogens:viruses,bacterial,otherpathogensHostandenvironmentalfactorsClassificationofrespiratoryinfectionsClassificationofRespiratoryInfectionsAccordingtotheleveloftherespiratorytreemostinvolved:UpperrespiratorytractinfectionLowerrespiratorytractinfectionCase-1Jack,agefourmonths,issentathomebyhisgeneralpractitionerbecauseoftwodaysofcough,rapid,labouredbreathingandpoorfeeding.Hewasbornat27weeks’gestation,birthweight979gandwasdischargedhomeatthreemonthsofage.Onexaminationhewasafeverof37.4Candarespiratoryrateof60breaths/min.Hischestishyperinflatedwithmarkedintercoastalrecession.Onauscultationtherearegeneralizedfinecracklesandwheezes.QuestionDoyouhaveanycommentsorwhatdoyouconcludeanythingfromthiscase?Case-1Jack,agefourmonths,issentathomebyhisgeneralpractitionerbecauseoftwodaysofcough,

rapid,labouredbreathingandpoorfeeding.Hewasbornat27weeks’gestation,birthweight979gandwasdischargedhomeatthreemonthsofage.Onexaminationhewasafeverof37.4Candarespiratoryrateof60breaths/min.

Hischestishyperinflatedwithmarkedintercostalrecession.Onauscultationtherearegeneralizedfinecracklesandwheezes.PneumoniaQuestionWhatispneumonia?

Pneumoniaisaninflammationoftheparenchymaofthelungs.Typicalmanifestations:cough,fever,tachypnea（氣促）,cyanosis（紫紺）,rales（濕啰音）DefinitionQuestionHowabouttheprevalenceofpneumonia?

Pneumoniaaccountsforapproximately15%ofallrespiratorytractinfectionsWorldwide,about3millionchildrendieeachyearfrompneumonia,withthemajorityofthesedeathsoccurringindevelopingcountriesPneumoniaremainsthemostcommoncauseofmorbidityinChinaIncidenceTheGlobalburdenofChildhoodDiseases

Mortality:MaincausesU5(ProfessorandChair,DepartmentofInternationalHealth,JohnsHopkinsBloombergSchoolofPublicHealth,USA)Globally,morethan10millionchildrenunderfiveyearsofagedieeachyear,usuallydueto:

19%Pneumonia18%Diarrhoea10%Neonatalsepsis/pneumonia8%Malaria-pretermdeliveryasphyxiaatbirthQuestionHowtoclassifypneumoniasclinically?

AnatomyPathogensSeverityDurationOnsetsiteClassificationBronchopneumonia（支氣管肺炎）LobarorLobularPneumonia（大葉性或節(jié)段性肺炎）InterstitialPneumonia（間質性肺炎）BasedonanatomyorX-raymanifestation

Basedonetiology

BacterialPneumoniaViralPneumoniaMycoplasmaPneumoniaChlamydia

Pneumonia

AcutePneumoniaProlongedPneumoniaChronicPneumoniaBasedonthecourseofpneumonia

MildPneumoniaSeverePneumoniaBasedontheseverityofpneumonia

CommunityAcquiredPneumonia(CAP)HospitalAcquiredPneumonia(HAP)BasedontheonsetsiteofpneumoniaCommonpathogensincommunityandhospitalinfectionCommunity-acquiredinfectionViruses

Streptococcuspneumoniae（肺炎鏈球菌）Haemophilusinfluenzae（流感嗜血桿菌）Mycoplasmapneumoniae（肺炎支原體）Chylamidia（衣原體）Staphyloccocusaureus（金黃色葡萄球菌）Hospital-acquiredinfectionGram-negativebacteriaPseudomonasaeruginosa（銅綠假單胞菌）Klebsiellapneumoniae（肺炎克雷伯菌）Escherichiacoli（大腸桿菌）StreptococcuspneumoniaeStaphylococcusaureusAnaerobes（厭氧菌）Fungi（真菌）BronchopneumoniaQuestionWhyarechildrenlikelyhavebronchopneumonia?

CharactersofchildhoodairwayanatomicstructureandtheirrespiratoryphysiologyImmunefunctionofchildhoodHighriskfactors:prematurebaby,underlyingdisordersQuestionWhatcausebronchopneumonia?

?Bacteria:Streptococcuspneumoniae,Haemophilusinfluenzae,Moraxellacatarrhalis（卡他莫拉菌），Staphyloccocusaureus?Viruses:RSV,IV,ADV,MPV,etal.?MycoplasmaCausesofBronchopneumonia?Bacteria:Streptococcuspneumoniae,Haemophilusinfluenzae,Moraxellacatarrhalis（卡他莫拉菌），Staphyloccocusaureus?Viruses:RSV?MycoplasmaCausesofBronchopneumoniaPathologyofPneumoniaNormalPneumoniaInflammaoryexudateInflammaoryexudatePathologyofPneumoniaQuestionWhatarethepathophysiologyofpneumonia?PathogensURTIBronchitisPneumoniaInflammatoryexudateObstructionofairwayGasexchangeabnormalVentilationabnormalhypoxemia(低氧血癥）hypercapnia（高碳酸血癥）toxinemia（毒血癥）tachypneacyanosisralesfevercoughSeverePneumoniaRespiratoryfailure

PO2≤6.67kPaPCO2≥6.67kPaToxiccarditisandDICToxicencephalopathy（中毒性腦?。〥igestivesystemsymptom

abdomendistensionbloodydiarrheaDisturbancesoffluidandelectrolyte

metabolicacidosisrespiratoryacidosishyponatremiaQuestionWhatarethesignsandsymptomsofpneumonia?

Theclinical

signsandsymptomsofpneumoniadependprimarilyonthe

age

ofthepatient,the

causativeorganism,andthe

severity

ofthediseaseFeverCoughCyanosisTachypeneaRalesAgerangeDefinitionof“fastbreathing”Upto2months>60breaths/minute2-12months>50breaths/minute

1-5years

>40breaths/minuteAge-realtedrespiratoryratesindicativeofalowerrespiraotrytractinfection

out

breathinginWithinspiration,thesideofthenostrilsflaresoutwardsNasalFlaring（鼻扇）Withinspiration,thelowerchestwallmovesinLowerChestWallIndrawing

out

breathinginFeverCoughCyanosisTachypeneaRales

Classicfindingsofpneumoniathatoccurinadultsandolderchildren,suchas

fever,coughandrales,

areoften

absent

ininfants

andtoddlersGenerallypresentwith

nonspecific

signsand

symptomsincluding

lethargy,irritability,

poorfeeding,

vomitingIfitappearrespiratoryfailureorotherabnormalityofothersystem-severepneumonia.ImportantPointsSeverePneumoniaRespiratoryfailure

PO2≤6.67kPaPCO2≥6.67kPaToxiccarditisandDIC

tachycardiapaleECGabnormalToxicencephalopathyirritabilitylethargyvomitingseizureDigestivesystemsymptom

abdomendistensionbloodydiarrheaComplicationsEmpyema（膿胸）Pyopneumothorax（膿氣胸）Pneumatocele（肺大皰）Lungabscesses（肺膿腫）Atelectasis（肺不張）LaboratoryExamination

WhitebloodcellcountandC-reactionproteinPathogensexamination:1)Sputumcultures2)Bloodcultures3)RapidscreeningtestsforvirusorbacterialBronchoscopyBloodgasanalysis:hypoxiaand/orhypercapniaRadiographEvaluation

TypicalX-raymanifestationofbronchopneumoniaispatchyinfiltratesbilaterallyComplication:lungabscesses,empyema,pyopneumothorax,pneumatocele,atelectasisCT

NormalchestX-ray正常胸片支氣管肺炎Patchyinfiltrates大葉性肺炎NormalConsolidation膿氣胸Normalpyopneumothorax肺膿腫Normallungabscesses肺大皰Normalpneumatocele

左側肺不張NormalatelectasisQuestionHowtodiagnosispneumoniaclinically?

AccordingtothetypicalclinicalmanifestationofbronchopneumoniaAccordingtoX-raymanifestationPayattentiontotheatypicalmanifestationofinfantsEvaluatetheseverityofpneumoniaFindtheetiologyofpneumoniaDifferentialDiagnosis

BronchitisForeignBodyAspirationTuberculosisAsthmaQuestionHowispneumoniatreated?

Management

SupportivecareAntimicrobialstherapyHospitalizationinselectedcases

SupportiveCare

Respiratorycaremayrangefromoxygenation,

bronchodilatorsforwheezing,humidificationormist,suctioning,andposturaldrainage,

intubationandmechanicalventilationHydration(sometimesintravenous)

Controloffever:brufen,acetaminophenManagementofcomplicationsAntimicrobialTherapyOrganismAntimicrobialS.pneumoniae

Penicillin(ifnotresistant).third-generationcephalosporine.g.cefotaxime\ceftriaxone(ifresistanttopenicillin)H.influenzae

AzithromycinorAmoxicillin(ifnotresistant)Betalactamase

Cefuroximeorthird-generationcephalosporin(ifbetalactamaseandresistant)S.aureusMethicillin(ifnotresistant)Vancomycin(ifMRSA-methicillinresistantS.aureus)ifpenicillinallergy:vancomycin,clindamycin

Chlamydia

Azithromycin(othermacrolidese.gerythromycin);alternative,sulfadrugs

MycoplasmaAzithromycin(othermacrolides);alternative,tetracycline(ifolderthan8years)

RSV

Ribavirin(optional)InfluenzaAmantadine(ifsevere)BacteriaAtypicalVirusesAgeGroup

Bacterial

Viral

EmpiricTherapyNeonate(0-28days)GroupBstreptococcus,gram-negativeentericE.coli,Klebsiella,Listeriamonocytogenes,S.aureus,othergram-positive)CytomegalovirusHerpessimplexAmpicillinandaminoglycoside(gentamicinortobramycinoramikacin,orthird-generationcephalosporin).Note:Avoidceftriaxone2°tobilirubin

Infants3-16weeks;afebrilepneumoniainfancy

ChlamydiatrachomatisUreaplasmaurealyticumCytomegalovirusPneumocystiscariniiErythromycinSulfonamideInfantsfebrileorillappearingage1-3monthsSameorganismsasforneonateplusS.pneumoniae,H.influenzae,S.aureusNotapplicableAntibiotic(nafcillin,oxacillin,ormethacillin)Broad-spectrumcephalosporin(e.g.,cefotaxime)ToddlerorpreschoolageS.pneumoniae,H.influenzaeM.pneumoniae,ChlamydiaRSVParainfluenzaAdenovirusInfluenzaAzithromycin

Amoxacillin-clavulanate:notactiveagainstatypicalorganisms(Mycoplasma,Chlamydia)

OrganismsCausingPneumoniaandEmpiricTherapyinPediatric

BacteriaAntibioticsDurationG+coccusPenicillin，1stand2ndcephalosporin7—10daysG-bacillus2ndand3rdcephalosporin1—2weeks

S.aureus

PiperacillinSodium

，Vancomycin

3—4weeksM.pneumoniaeMacrolides2—3weeksQuestionHowabouttheclinicalcourseofpneumonia?

Withtreatment,pneumoniacausedbybacteriacanusuallybecuredin1or2weeksPneumoniacausedbyavirusoftenlastslongerClinicalCourseSeveralPneumonias

BronchiolitisisthemostcommonseriousrespiratoryinfectionofinfancyTwotothreepercentofallinfantsareadmittedtohospitalwiththediseaseeachyearduringannualwinterepidemicsRespiratorysyncytialvirus(RSV)isthepathogenin75-80%casesClinicalfeatures:Age:2-6monthSeasonWheezingX-rayDuration:7-10daysBronchiolitisHyperinflationofthelungswithflatteningofdiaphragmInvestigations

RSVcanbeidentifiedrapidlyusingafluorescentantibodytestonnasopharyngealsecretionsThechestX-rayshowshyperinflationofthelungsduetosmallairwaysobstructionandairtrappingBloodgasanalysis,whichisrequiredinonlythemostseverecases,showsloweredarterialoxygenandraisedCO2tensionManagement

Supportive.Humidifiedoxygenisdeliveredintoahead-boxMist,antibioticsandsteroidsarenothelpfulNebulisedbronchodialatorsdonotreducetheseverityordurationoftheillnessTheantiviraldrugribavirinonlymarginallyshortensviralexcretionandclinicalsymptoms,andshouldbeconsideredonlyforinfantswithunderlyingcardiopulmonarydisordersorimmunodeficiencyFluidsmayneedtobegivenbynasogastrictubeorintravenouslyMechanicalventilationisrequiredinabout2%ofinfantsadmittedtohospitalThereareover60typesofadenoviruses,whichaccountfor2-10%ofallrespiratoryillnessesAdenoviralinfectionsarecommonearlyinlife,itisespeciallycommoninlessthan2year-oldEpidemicrespiratorydiseaseoccursinwinterandspringHighgradefever,severesymptomsofsystemicpoisoning,andmultipleorgandamage.

Symptomspersistfor2-4weeksChestX-rearshowbilateralperibronchialandinterstitialinfiltratesAdenoviralpneumoniacanbenecrotizingandcausepermanentlungdamage,especiallybronchiectasisThereisnospecifictreatmentAdenoviralPneumoniaStaphylococcusaureusPneumonia

S.aureusisanuncommonbutimportantcauseofpneumoniathatcanoccurinanyagegroup

S.aureusisarapidlyprogressivefulminantillnessS.aureuspneumoniaeasilyoccurscomplicationsBloodculturesarepositivein20-30%ofpatientsThepleuraleffusionsshouldbedrainedbythoracentesisor,iflarge,byachesttube

Pneumatocelesarealsocommonandarefoundin45-60%ofpatientswithS.aureuspneumoniaMethicillinorvancomycinshouldbeadministeredfor3-4weeksMycoplasmaPneumonia

MpneumoniaeisacommoncauseofsymptomaticpneumoniainolderchildrenEndemicandepidemicinfectioncanoccurTheincubationperiodislong(2-3weeks),andtheonsetofsymptomsisslowAlthoughthelungistheprimaryinfectionsite,extrapulmonarycomplicationssometimesoccurClinicalFeatures

Fever,cough,headache,andmalaisearecommonsymptomsastheillnessevolvesRalesarefrequentlypresentonchestexamination,decreasedbreathsoundsordullnesstopercussionovertheinvolvedareamaybepresentLaboratoryfindings

ThetotalanddifferentialwhitebloodcellcountsareusuallynormalThecoldhemagglutinintitiershouldbedetermined,becauseitmaybeelevatedduringtheacutepresentation.Atiterof1:64orhighersupportsthediagnosisImagingChestx-raysusuallydemonstrateintersititialorbronchopneumonicinfiltrates,frequentlyinthemiddleorlowerlobes.Pleuraleffusionsareextremelyuncommon.Complications

Extrapulmonaryinvolvementoftheblood,CNS,skin,heart,orjointscanoccurDirectCoombs-positiveautoimmunehemolyticanemia,CoagulationdefectsandthrombocytopeniacanalsooccurAwidevarietyofskinrashesincludingerythemamultiformaandStevens-JohnsonsyndromeTreatment

AntibiotictherapywitherythromycinorAzithromycin

for7-10daysusuallyshortensthecourseofillnessSupportivemeasures,includinghydration,antipyretics,andbedrest,arehelpfulChlamydialPneumonia

PulmonarydiseaseduetoCtrachomatisusuallyevolvesgraduallyastheinfectiondescendstherespiratorytractInfantsmayappearquitewelldespitethepresenceofsignificantpulmonaryillnessAppropriateage:2-12weeksInclusionconjunctivitis,eosinophilia,andelevatedimmunoglobulinscan

beseenClinicalFeatures

About50%ofpatientswithchlamydialpneumoniahaveactiveinclusionconjunctivitisorahistoryofitRhinopharyngitiswithnasaldischargeorotitismediamayhaveoccurredormaybycurrentlypresentCoughisusuallypresent.ItcanhaveastaccatocharacterandresemblethecoughofpertussisTheinfantisusuallytachypenic.Scatteredinspiratoryralesarecommonlyheard,butwheezesrarelySignificantfeversuggestsadifferentoradditionaldiagnosisLaboratoryfindings

Althoughpatientsmayfrequentlybehypoxemic,CO2retentionisnotcommonPeripheralbloodeosinphiliahasbeenobservedinabout75%