英文版-Indiana-University-Purdue-University-Fort-Wayne微生物學(xué)授課講義-lecture-14課件_第1頁
英文版-Indiana-University-Purdue-University-Fort-Wayne微生物學(xué)授課講義-lecture-14課件_第2頁
英文版-Indiana-University-Purdue-University-Fort-Wayne微生物學(xué)授課講義-lecture-14課件_第3頁
英文版-Indiana-University-Purdue-University-Fort-Wayne微生物學(xué)授課講義-lecture-14課件_第4頁
英文版-Indiana-University-Purdue-University-Fort-Wayne微生物學(xué)授課講義-lecture-14課件_第5頁
已閱讀5頁，還剩21頁未讀， 繼續(xù)免費(fèi)閱讀

下載本文檔

版權(quán)說明：本文檔由用戶提供并上傳，收益歸屬內(nèi)容提供方，若內(nèi)容存在侵權(quán)，請進(jìn)行舉報(bào)或認(rèn)領(lǐng)

文檔簡介

LegionellaBIOL533Lecture14MedicalMicrobiologyBIOL5331HistoryAmericanLegionConventionin1976inPhiladelphiahotelRespiratorydistressandfever200affected34diedBIOL5332HistorySixmonthsafteroutbreak,CDCisolatedbacteriafrompost-mortumlungtissueInoculatedlungtissueintoperitonealcavityofguineapigsAfteranimalbecameill,removeditsspleenandinjectedtissueintofertilizedchickeneggs(rickettsialmethodology)BIOL5333HistoryOrganismwasthoughttobeunique,givennewgenusandspeciesname:

LegionellapneumophilaEpidemiologicalsearchrevealedoutbreakinsamehoteltwoyearsearlierCultureproblemsbecauseorganisms:DonotgrowoncommonlaboratorymediaDonotreadilystainBIOL5334MicrobialPhysiology

andStructureFamilyLegionellaceaeOnegenus:Legionella25speciesand42serotypesLegionellapneumophila

responsiblefor85%ofinfections(serotype1mostcommon)BIOL5335MicrobialPhysiology

andStructureSpeciescanbedifferentiatedby:DNAhomologyCellwallfattyacidsBiochemicaltestingImmunologicalserotypingBIOL5336MicrobialPhysiology

andStructureMorphologyGram—rods(pleomorphiconartificialmedia)DonotstainwellexceptwithspecialsilverstainCulture:donotgrowinordinarylabmedia,eventhoughtheyareaerobicorganismsRequirehighconcentrationofcysteineandareinhibitedbysodiumionsandaromaticcompoundsBIOL5337MicrobialPhysiology

andStructureMediadevelopedhave:CharcoaltoabsorbaromaticcompoundsNon-sodiumionbufferAntibioticstosuppressotherorganismsDyestomakecoloniesvisibleonsolidmediaBIOL5338PathogenesisEncounter:aquatic;foundinlakesandstreamsLargenumbersinpollutedwateraroundpowerstationsCanliveinchlorinateddrinkingwaterNormallyfoundinhotwatertanksofbuildingsGetintopipesandmultiplyinsedimentandaccumulateoverperiodofyearsDonotspreadfrompersontopersonSedimentprovidesshelteraswellasnutritionforotherbacteriathatcansupplycysteineBIOL5339PathogenesisEntry,spread,andmultiplicationEntry:inhalationoforganismsIncubationperiod:2-10daysInitialhostresponse:acuteinflammatoryresponseofaveoliandthenbronchioles(similartopneumococcalinfection)NeutrophilsaccumulatefollowedbymacrophageBIOL53310PathogenesisDifferentfrompneumococcalinfectionOrganismslocatedinsideofmacrophageInhibitlysosomalfusionandacidificationofphagocyteBIOL53311DamageOrganismpossessesseveralexotoxinsProteases,hemolysins,andothercytotoxinsOneinhibitsoxidativekillingofneutrophilsMayalsodamagetissuedirectlySpreadrapidlyinlungtissueSymptomsresultingfrominflammatorydiseaseinlungCough,chestpains,abnormalbreathingsounds,andfeverBIOL53312DamageOthertargetsites:heart,kidney,lymphnodes,spleen,liver,andbrainNeurologicalsymptomsanddiffusemetabolicabnormalitiesresultfrombloodstreaminvasion:confusion,deliriumSomepatientshavegastrointestinalsymptoms,includingdiarrheaBIOL53313DiseaseSyndromesIngeneral,healthypeoplerarelygetdiseaseImmunosuppressedpatientsandheavysmokerswithahistoryofrespiratoryproblemsBIOL53314DiseaseSyndromesPontiacfever(flu-likeillness)Pontiac,Michiganin1968Symptoms:fever,chills,muscleaches,malaise,headacheDevelopsover12-hourperiod,persistsfor2-5days,thenspontaneouslyresolvesMinimalmorbidityandnomortalityBIOL53315DiseaseSyndromesLegionaire’sdiseaseMuchmoresevere,withhighmortalityunlesspromptlytreatedOverallmortalityis15-20%SymptomsreviewedinPathogenesissectionBIOL53316EpidemiologyIncidenceispoorlyunderstoodbecausediseasedocumentationisdifficultPneumoniasduetoorganism:lessthan1%togreaterthan30%Estimatedthat25,000to50,000casesoccurannuallyBIOL53317EpidemiologyTimeofyearSporadicinfectionsthroughoutyearEpidemicinfectionsoccurinlatesummerandfallElderlywithdecreasedpulmonaryfunctionandcellularimmunityareatincreasedriskBIOL53318LaboratoryDiagnosisMicroscopyDifficultbecauseoflackofstainingintracellularnatureRequirelargenumberoforganismstodetectBesttest:directfluorescentantibodyTestisveryspecificFalsepositivesobservedrarelywithPseudomonas,Bacteriodes,andotherorganismsBIOL53319LaboratoryDiagnosisCulture:bufferedcharcoalyeastextract(BCYE)Growafter3-5daysAppearassmallcolonieswithgroundglassappearanceBIOL53320LaboratoryDiagnosisDetectionofAginrespiratorysecretionsorurineCanbedetectedimmunologicallyorbyhybridizationExcretioninurinecanoccurforaslongasayearBIOL53321LaboratoryDiagnosisSerology:indirectfluorescentantibodytestFour-foldorgreaterincreaseinantibodytiterResponsecanbedelayedaslongaseightweeksBIOL53322LaboratoryDiagnosisIdentificationDemonstrationoftypicalmorphologyandgrowthrequirementsGram—bacteria(pleomorphicandweaklystraining)GrowthonBCYEwithcysteinebutnoBCYEConfirmationbyfluorescentantibodyBIOL53323TreatmentErythromycinisantibioticofchoiceCanpenetratewhitebloodcellsMoststrainspossess-lactamasesBIOL53324Prevention

溫馨提示

  • 1. 本站所有資源如無特殊說明，都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等，如果需要附件，請聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙，網(wǎng)頁內(nèi)容里面會有圖紙預(yù)覽，若沒有圖紙預(yù)覽就沒有圖紙。
  • 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
  • 5. 人人文庫網(wǎng)僅提供信息存儲空間，僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理，對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯，并不能對任何下載內(nèi)容負(fù)責(zé)。
  • 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容，請與我們聯(lián)系，我們立即糾正。
  • 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時(shí)也不承擔(dān)用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。

評論

0/150

提交評論