级课件-儿传猩红热

Scarlet猩红 ScarletfeverisanacuterespiratoryinfectioncausedbyGroupAβ-hemolyticstreptococci(GAS,S.Pyogenes)whichproduceerythrogenictoxins. Fever,pharyngitis,scarletmaculesovergeneralizederythema,anddesquamationinconvalescentstage.Streptococciaregram-positivecoccithatgrowinpairsorvariable-lengthchainsCompleteβ-hemolyticPartiallyα-hemolyticNoγ-hemolytic一、 不溶血丙型 部份溶 甲型 完全溶血乙型C抗

A~HK~V20群（组M蛋 猩红热病原：A组乙型（β）溶血性链球菌VirulenceofGroupAβ–hemolytic(S.StructuralcompositionsofLipoteichoicacid(LPA)MproteinFibronectin-bindingprotein(proteinF)ThecellwallreceptorErythrogenictoxinsErythrogenictoxinsareresponsiblefortherash,fever,pusformationofscarletfever.Therearethreeantigenicallydistincterythrogenictoxins:typeA,B,andC. Antibodiestotheerythrogenictoxinspreventdevelopmentofarashbutdonotprotectagainsttheunderlyinginfection.VirulenceofGroupAβ–hemolytic(S.StructuralcompositionsofExtracellularproductsofErythrogenictoxins(Pyogenicexotoxins)HyaluronicAcidCapsuleHemolysinO,HemolysinS(SLO&SLS)Streptokinase(SK)Streptodornase(SD)SourcesofInfectionHighlyinfectivestagerangesfrom24hoursbeforesymptomappearingtothefastigiumofBacterianose,mouth,throat,respiratorytractandskinRoutesofrespiratorydropletsdirectindirectPopulation Thediseasemostcommonlyaffectspre-schoolageandschoolagechildren. 80%of10-years-oldchildrenhasdevelopedlifelongprotectiveantibodiesagainstErythogenicIncidenceislowestamongPopulationpost-infectiousantibacterialantitoxic抗菌免 抗毒免post-infectious+-+--++-sufferfrom????Epidemic Circulatingtrend:casesofscarletfeverhavebeendecreasingandbecamemilderinthelastfiftyyears.Themortalitydroppedfrom10-20%in1930stolessthan1%in1990s.Severecasesrarelyhappennowadays. Peakseason:casescanbeobservedaroundthewholeyearbutaremostprevalentinwinterandspring.咽峡炎、化脓性扁桃A组乙溶血 飞

释 毒血症状：发红 入毒皮

全身不真皮层毛细血管 皮肤弥漫性充血发 毛囊周围 粟粒肤表皮细胞角化、坏 脱屑或脱Incubation1-7daysfromexposuretotheonsetofTheaverageis2-4TypicalscarletMildscarlet LikeSyndrome(STSS) SurgicalScarletFeverandPuerperalScarletProdromalRashConvalescentProdromalperiod:1~2----Whitestrawberry--Toxicsymptoms:Chills,headache,vomiting,myalgias,andmalaise--TenderSubmaxillary&cervicalRash

Within24-48hoursafter----Redstrawberry----Toxic----TenderSubmaxillary&cervicalConvalescent--Feverandsubsidewithdisappearanceof--Thedurationandextentofdesquamationvarywiththeintensityoftherash.Itmaycontinueforaslongas6wk.------Mildscarlet Actuallymanychildrenwithactiveinfectionmayhavemildersymptoms,withonlyafewofslight Highrateofmisdiagnosisandmisseddiagnosisintheout-patientclinic. Somemildcasesofscarletfeverwillgoawayinaboutaweekevenwithouttreatment.------StreptococcalToxicShock-LikeSyndrome Beassociatedwithstreptococcalstrainsthatproducethepyrogenicexotoxins paniedbysystemDifficulttodistinguishfromstaphylococcalTSSuntilresultsofculturesareobtained------Surgicalscarlet-----Surgicalscarlet-----Puerperalscarlet Scarletfeveroccasionallyhappensaftertheinfectionofsomepartofthefemalereproductiveorgans(,vaginaanduterus)followingachildbirthoranabortion,alsocalledchildbedfever. Casesoffeverof38℃andhigherduringthefirst10daysfollowingdeliveryormiscarriage.ExtensionfromtheSinusitis,Otitismedia,Mastoiditis,Cervicallymph-adenitis,Retropharyngealorparapharyngealabscess,Peritonsillarabscess,Bronchop HematogenousSepsis,Meningitis,Osteomyelitis,Septicarthritis,Brainabscess,IntracranialvenoussinusthrombosisToxichepatitis,toxictoxicmyocarditis,toxicThroatswabThroatcultureisthecriterionstandardforconfirmationofgroupAstreptococcalDirectantigenRapidantigenStreptococcalantibodyAnincreaseinanti–streptolysinO(ASO)titerscanbeobservedwithinthefirst3-6wkafterinfection.ASOtestisusedtoconfirmpreviousgroupAstreptococcalinfection.ASOtitersmaybemodifiedorabolishedearlyandeffectiveantibioticCompletebloodWhitebloodcell(WBC)countinscarletfevermayincreaseto12,000-16,000/mm3,withadifferentialofupto95%neutrophilExposuretoscarletTheabruptonsetofFever,pharyngitis,headache,vomiting,malaise, Atypicalofthesandpaper-likerashin24-48hrfollowingtheonsetoffeverandspreadingalloverthebodywithin24hrPastia'sCircumoral WhitestrawberrytongueorredstrawberrySepsiscausedbyErythrogenictoxin-producingstrainsofStaphylococcusaureus.DrugKawasakiDiseaseKeyPointsfor(1).Pharyngitis(2).24-48hrintervalbetweenfeverandonsetof (3).Specificrash(4).IncreasedWBCcountandNC Pre-schoolageandschoolagechildren(6).GoodcurativeeffecttoPenicillinPenicillinPenicillin50,000-200,000u//kgddividedbidfor7-20~30mg/kg/ddividedbidfor7-10Completionoftheantibioticregimenisquiteessential!Afterantibiotictreatmentfor1-2days,thefever,rash,andothersystemicmanifestationswillsubsiderapidly,andthechildrenmaylookwell,buttheregimenofantibioticshouldbecontinuetoeliminatethesmallamountofbacteriaremainedinthebodyinordertopreventrelapseandcomplications.Anti-pyretic(paracetamol)canbewhennecessaryforfever,headacheorthroatEatingsoftfoodsanddrinkingplentyofcoolliquids,particularlyifthethroatisverypainful.Oralantihistaminesorcalaminelotiontorelievetheitchofrash.Patientshouldbeisolateduntil24hafterantibiotictreatedControlofsourcesofAbruptthewaysofProtectthe Itisaseverediseaseinthepre-antibioticerabecauseofitscomplications.Theprognosisforadequa