Topics

RespiratorydisordersRespiratoryinfectionsPneumoniaRespiratoryDisorders50%ofconsultationwithgeneralpractitionersoracuteillnessinyoungchildrenandathirdofconsultationsinolder

children20-35%ofacutepediatricadmissionstohospital,someofwhicharelife-threateningAsthma

isthemostcommonchronicillnessofchildhoodCysticfibrosisisthemostcommoninheriteddisorderinCaucasianscausingchronicdiseaseRespiratoryInfections

Themostfrequentinfectionsofchildhood:6-

8/yearPathogens:viruses,bacterial,otherpathogensHostandenvironmentalfactorsClassificationofrespiratoryinfectionsClassificationofRespiratoryInfectionsAccordingtotheleveloftherespiratorytreemostinvolved:UpperrespiratorytractinfectionLowerrespiratorytractinfectionPneumoniaEnmeiLiuChildren’sHospital,CMUCase-1Jack,agefourmonths,issentathomebyhisgeneralpractitionerbecauseoftwodaysofrapid,labouredbreathingandpoorfeeding.Hewasbornat27weeks’gestation,birthweight979gandwasdischargedhomeatthreemonthsofage.Onexaminationhewasafeverof37.4Candarespiratoryrateof60breaths/min.Hischestishyperinflatedwithmarkedintercoatalrecession.Onauscultationtherearegeneralizedfinecracklesandwheezes.QuestionDoyouhaveanycommentsorwhatdoyouconcludeanythingfromthiscase?Case-1Jack,agefourmonths,issentathomebyhisgeneralpractitionerbecauseoftwodaysofrapid,labouredbreathingandpoorfeeding.Hewasbornat27weeks’gestation,birthweight979gandwasdischargedhomeatthreemonthsofage.Onexaminationhewasafeverof37.4Candarespiratoryrateof60breaths/min.

Hischestishyperinflatedwithmarkedintercoatalrecession.Onauscultationtherearegeneralizedfinecracklesandwheezes.QuestionWhatispneumonia?

Pneumoniaisaninflammationoftheparenchymaofthelungs.

DefinitionQuestionHowabouttheprevalenceofpneumonia?

Pneumoniaaccountsforapproximately15%

ofallrespiratorytractinfections.Worldwide,about3millionchildrendieeach

yearfrompneumonia,withthemajorityof

thesedeathsoccurringindevelopingcountries.Pneumoniaremainsthemostcommoncauseof

morbidityinChina.IncidenceQuestionHowtoclassifypneumoniainclinic?

AnatomyPathogensSeverityDuration

OnsetsiteClassification

BronchopneumoniaLobarorLobularPneumoniaInterstitialPneumoniaBasedonanatomyorX-raymanifestation

Basedonetiology

BacterialpneumoniaViralPneumoniaMycoplasmaPneumoniaChlamydia

Pneumonia

AcutePneumoniaProlongedPneumoniaChronicPneumoniaBasedontheprocessofpneumonia

MildPneumoniaSeverePneumoniaBasedontheseverityofpneumonia

CommunityAcquiredPneumonia(CAP)HospitalAcquiredPneumonia(HAP)BasedontheonsetsiteofpneumoniaBronchopneumoniaQuestionWhyarechildrenlikelyhavebronchopneumonia?

Charactersofchildhoodairwayanatomic

structureandtheirrespiratoryphysiologyImmunefunctionofchildhoodHighriskfactors:prematurebaby,underlying

disordersQuestionWhatcausebronchopneumonia?

?Bacteria:Streptococcuspneumoniae,Haemophilusinfluenzae?Viruses?MycoplasmaCausesofBronchopneumoniaPathologyofPneumoniaInflammaoryexudateInflammaoryexudatePathologyofPneumoniaQuestionWhatarethepathophysiologyofpneumonia?PathogensURTIBronchitisPneumoniaInflammatoryexudateObstructionofairwayGasexchangeabnormalVentilationabnormalhypoxemiahypercapniatoxinemiatachypneacyanosisralesfevercoughQuestionWhatarethesignsandsymptomsofpneumonia?

Theclinical

signsandsymptomsofpneumoniadependprimarilyonthe

age

ofthepatient,the

causativeorganism,andthe

severity

ofthedisease.FeverCoughCyanosisTachypeneaRalesout

breathinginWithinspiration,thesideofthenostrilsflaresoutwardsNasalFlaringWithinspiration,thelowerchestwallmovesinLowerChestWallIndrawingout

breathinginFeverCoughCyanosisTachypeneaRales

Classicfindingsofpneumoniathatoccurin

adultsandolderchildren,suchas

fever,cough

and

rales,

areoften

absent

ininfants

andtoddlers.Generallypresentwith

nonspecific

signsand

symptomsincluding

lethargy,irritability,

poor

feeding,

vomiting.Ifitappearrespiratoryfailureorother

abnormalityofothersystem-severepneumonia.

ImportantPointsComplications

EmpyemaPyopneumothoraxPneumatocele

LungabscessesAtelectasisLaboratoryExamination

WhitebloodcellcountandC-reactionprotein

Pathogensexamination:

1)Sputumcultures

2)Bloodcultures

3)RapidscreeningtestsforvirusorbacterialBronchoscopyBloodgasanalysis:hypoxiaand/orhypercapniaRadiographEvaluation

TypicalX-raymanifestationof

bronchopneumoniaispatchyinfiltrates

bilaterallyComplication:lungabscesses,empyema,

pyopneumothorax,pneumatocele,atelectasisCT

NormalchestX-rayPatchyinfiltratesLobarpneumoniaoftherightlowerzone

consolidationlungabscessespyopneumothoraxQuestionHowtodiagnosispneumoniaclinically?

Accordingtothetypicalclinicalmanifestation

ofbronchopneumonia.AccordingtoX-raymanifestation

Payattentiontotheatypicalmanifestationof

infantsEvaluatetheseverityofpneumoniaFindtheetiologyofpneumoniaDifferentialDiagnosis

BronchitisForeignBodyInspirationTuberculosisQuestionHowispneumoniatreated?

Management

SupportivecareAntimicrobialstherapyHospitalizationinselectedcases

SupportiveCareAdolescents.

Respiratorycaremayrangefromoxygenation,

bronchodilatorsforwheezing,humidificationor

mist,suctioning,andposturaldrainage,intubation

andmechanicalventilation.Hydration(sometimesintravenous)

ControloffeverManagementofcomplicationsAntimicrobialTherapy

Adolescents.OrganismAntimicrobialS.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

QuestionHowabouttheclinicalcourseofpneumonia?

Withtreatment,pneumoniacausedby

bacteriacanusuallybecuredin1or2weeksPneumoniacausedbyavirusoftenlastslongerClinicalCourseAdolescents.SpecificPneumoniasBrochiolitis

Brochiolitisisthemostcommonserious

respiratoryinfectionofinfancyTwotothreepercentofallinfantsareadmittedto

hospitalwiththediseaseeachyearduringannual

winterepidemics.Ninetypercentareaged1-9monthsbronchiolitisisrare

afteroneyearold.Respiratory

syncytialvirus(RSV)isthepathogenin75-

80%casesClinicalFeatures

Coryzalsymptomsprecedeadrycoughandincreasing

breathlessness.Wheezingisoftenbutnotalwayspresent.Feedingdifficultiesassociatedwithincreasingdyspnoea

areoftenthereasonforadmissiontohospital.Recurrent

apnoeaisaseriouscomplicationininfantsin

thefirstfewmonthsoflife.Infantsbornprematurelywhodevelop

bronchopulmonary

dysplasiaandinfantswithcongenital

heartdiseasearemoreseverelyaffected.Thefindingonexaminationarecharacteristic:

Sharp,drycough

TachypnoeaSubcostalandintercostalsrecessionHyperinflationofthechest

Investigations

RSVcanbeidentifiedrapidlyusingafluorescentantibody

testonnasopharyngealsecretions.ThechestX-rayshowshyperinflationofthelungsdueto

smallairwaysobstructionandairtrapping.Bloodgasanalysis,whichisrequiredinonlythemost

severecases,showsloweredarterialoxygenandraised

CO2tension

HyperinflationofthelungswithflatteningofdiaphragmManagement

Issupportive.Humidifiedoxygenisdeliveredintoahead-

box

Mist,antibioticsandsteroidsarenothelpful

Nebulised

bronchodialatorsdonotreducetheseverityor

durationoftheillness

Theantiviraldrugribavirinonlymarginallyshortensviral

excretionandclinicalsymptoms,andshouldbeconsidered

onlyforinfantswithunderlyingcardiopulmonary

disordersorimmunodeficiency

Fluidsmayneedtobegivenbynasogastrictubeor

intravenously

Mechanicalventilationisrequiredinabout2%ofinfants

admittedtohospitalEtiology：Respiratorysyncytialvirus(RSV)isthepathogenin75-80%casesClinicalfeatures:Age:3-6monthSeasonWheezingX-rayDuration:7-10daysManagement:

BronchiolitisStaphylococcusaureus

.

S.aureusisanuncommonbutimportantcauseof

pneumoniathatcanoccurinanyagegroup.

S.aureusisarapidlyprogressivefulminantillnessS.aureus

pneumoniaeasilyoccurscomplications.Bloodculturesarepositivein20-30%ofpatients.The

pleuraleffusionsshouldbedrainedby

thoracentesisor,iflarge,byachesttube.

Pneumatocelesarealsocommonandarefoundin45-60%ofpatientswithS.aureuspneumonia.

Methicillinorvancomycinshouldbe

administeredfor3-4weeks.

MycoplasmaPneumonia

M

pneumoniae

isacommoncauseofsymptomatic

pneumoniainolderchildren.Endemicandepidemicinfectioncanoccur.Theincubationperiodislong(2-3weeks),andtheonset

ofsymptomsisslow.Althoughthelungistheprimaryinfectionsite,

extrapulmonarycomplicationssometimesoccur.ClinicalFeatures

Fever,cough,headache,andmalaisearecommon

symptomsastheillnessevolves.Ralesarefrequentlypresentonchestexamination,

decreasedbreathsoundsordullnesstopercussion

overtheinvolvedareamaybepresent.

Laboratoryfindings

Thetotalanddifferentialwhitebloodcell

countsareusuallynormal.Thecoldhemagglutinin

titiershouldbe

determined,becauseitmaybeelevated

duringtheacutepresentation.Atiterof1:64

orhighersupportsthediagnosis.

ImagingChestx-raysusuallydemonstrateintersititialorbronchopneumonicinfiltrates,frequentlyinthemiddleorlowerlobes.Pleuraleffusionsareextremelyuncommon.Complications

Extrapulmonaryinvolvementoftheblood,

CNS,skin,heart,orjointscanoccur

DirectCoombs-positiveautoimmunehemolytic

anemia,Coagulationdefectsand

thrombocytopeniacanalsooccurAwidevarietyofskinrashesincluding

erythemamultiformaandStevens-Johnson

syndromeTreatment

Antibiotictherapywitherythromycinfor7-10

daysusuallyshortensthecourseofillness.Supportivemeasures,includinghydration,

antipyretics,andbedrest,arehelpful.ChlamydialPneumonia

PulmonarydiseaseduetoCtrachomatisusuallyevolves

graduallyastheinfectiondescendstherespiratorytract.Infantsmayappearquitewelldespitethepresenceof

significantpulmonaryillness.Appropriateage:2-12weeksInclusionconjunctivitis,eosinophilia,andelevated

immunoglobulinscan

beseen.ClinicalFeatures

About50%ofpatientswithchlamydialpneumonia

haveactiveinclusionconjunctivitisorahistoryofitRhinopharyngitiswithnasaldischargeorotitismedia

mayhaveoccurredormaybycurrentlypresentCoughisusuallypresent.Itcanhaveastaccatocharacter

andresemblethecoughofpertussisTheinfantisusuallytachypenic.Scatteredinspiraotrt

ralesarecommonlyheard,butwheezesrarelySignificantfeversuggestsadifferentoradditional

diagnosis

Laboratoryfindings

Althoughpatientsmayfrequentlybehypoxemic,CO2retentionisnotcommon.Peripheralbloodeosinphiliahasbeenobservedin

about75%ofpatients.Serum

immunloglobulinsareusuallyabnormal.IgM

is

virtuallyalwayselevated,IgGishighinmany,and

IgA

islessfrequentlyabnormal.C

trachomatiscanusuallybeidentifiedin

nasopharyngealwashingsusingfluorescentantibody

orculturetechniques.ImagingChestx-raysusuallyrevealdiffuseinterstitialandpatchyalveolarinfiltrates,peribronchialthickening,orfocalconsolidation.Asmallpleuralreactioncanbepresent.Despitetheusualabsenceofwheezes,hyperexpansioniscommonlypresent.Treatment

Erythromycinorsulfisoxazoletherapyshould

beadministeredfor14days.Oxygentherapymayberequiredfor

prolongedperiodsinsomepatients.Summary

Pneumoniainpediatricpatientsencompassesawidespectrumofetiologiesandillnessfrommildtosevereandlifethreatening.Therapyshouldincludeanantibioticifabacteriaoratypicalbacteria(chlamydiaormycoplasma)issuspected.Noantibioticsarenecessaryforviralpneumonia.Supportivetherapyalsoincludesfevercontrol,maintenanceofhydrationandrespiratorycare.Closefollow-upisnecessaryinordertodetectanysecondarybacterialinfectionorthed