微生物學(xué) 第7章細(xì)菌感染的檢測方法與防治原則

細(xì)菌感染的檢測方法與防治原則CHAPTER7PrinciplesofDiagnosis,PreventionandTreatment

ofBacteriaInfection1ManifestationsofInfection

Signsandsymptoms(癥狀)varyaccordingtothesiteandseverityofinfection.Diagnosisrequiresacomposite(綜合的)ofinformation,includinghistory,physicalexamination,radiographic(X線的)findings,andlaboratorydata.

2MicrobialCausesofInfectionInfectionsmaybecausedbybacteria,viruses,fungi,andparasites.Thepathogenmaybeexogenous(acquiredfromenvironmentaloranimalsourcesorfromotherpersons)orendogenous(fromthenormalflora).

3細(xì)菌學(xué)診斷BacteriologicalDiagnosis4細(xì)菌感染的診斷方法ApproachofBacterialDiagnosis標(biāo)本Specimen形態(tài)檢測抗原檢測morphological,Antigendetection細(xì)菌學(xué)診斷凝集試驗沉淀試驗中和試驗,補體結(jié)合試驗血清學(xué)診斷分離鑒定IsolationandIdentification標(biāo)本：雙分血清5一、病原菌檢測BacterialDiagnosis61.SpecimenSelection,Collection,andProcessing

Afewgeneralrulesapplytoallspecimens

Thesampleshouldberepresentativeoftheinfectiousphase(階段).Contamination(污染)ofthespecimenmustbeavoidedbyusingsterile(無菌的)equipment.Thespecimenmustbetakentothelaboratoryandexaminedpromptly.71.SpecimenSelection,Collection,andProcessingAfewgeneralrulesapplytoallspecimensMeaningfulspecimenstodiagnosebacterialinfectionmustbesecured(獲得)

beforeantibioticareadministered.

Thequantityofmaterialmustbeadequate.Markerisimportant.8無菌采集早期采集采集適當(dāng)標(biāo)本盡快送檢，注意冷暖作好標(biāo)記，確保無誤采集雙份血清標(biāo)本的采集和送檢六原則1.Specimens92.ExaminationProcess標(biāo)本顯微鏡放大、染色鏡檢初步診斷分離培養(yǎng)明確診斷分子生物學(xué)技術(shù)：PCR,DNA雜交等培養(yǎng)特征形態(tài)特征生化試驗血清學(xué)鑒定動物試驗(毒力)藥物敏感試驗Ag的免疫學(xué)檢測101.鑒別細(xì)菌2.選擇抗菌藥物3.研究細(xì)菌致病性革蘭染色的意義11bacteriaInoculation接種incubation孵育antibioticpaper抗生素紙片result:

aclear,bacteria-freezone紙碟法藥物敏感試驗12常用于細(xì)菌學(xué)診斷的免疫學(xué)技術(shù)沉淀反應(yīng)Precipitation協(xié)同凝集反應(yīng)Coagglutination免疫熒光法ImmunofluorescenceIF對流免疫電泳CIECounterimmuno-electrophoresis酶免疫測定EnzymeimmunoassayEIA13SPA協(xié)同凝集試驗含SPA的葡萄球菌SPA(葡萄球菌A蛋白)可與IgG的Fc非特異結(jié)合，F(xiàn)ab仍可與抗原結(jié)合。14二、血清學(xué)診斷SerologicalDiagnosis151.原理Theantibodiesdirectedagainstthebacteriaarepresentintheserumofpatients,sotheidentificationofserumantibodieswithknownantigensisoftencalledserologicaldiagnosis.161.原理

用已知抗原檢測病人血清或體液中未知抗體及其量的變化，可作為感染性疾病的輔助診斷。由于抗體存在于血清或其他體液中，故常稱為血清學(xué)反應(yīng)或血清學(xué)診斷。172.標(biāo)本Inanacuteinfection,theantibodiesusuallyappearearly,andthenrisesharplyoverthenext10to21days.Thus,aserumsamplecollectedshortlyaftertheonsetofillness(acuteserum)andanothercollected2to3weekslater(convalescentserum恢復(fù)期血清)canbecomparedquantitatively(數(shù)量上)forchangesinspecificantibodycontent.18Thatis,detectablespecificantibodyisabsentfromtheacuteserum,butpresentintheconvalescentserum(恢復(fù)期血清).Alternatively,a4-foldorgreaterincreaseinantibodytiter(效價)supportsadiagnosisofrecentinfection.2.標(biāo)本192.

標(biāo)本血液，雙份急性期血清恢復(fù)期血清抗體效價比早期升高4倍以上，表明近期感染，具有診斷意義。203.血清學(xué)診斷方法

凝集試驗Agglutination：

肥達(dá)試驗、外斐試驗、顯凝試驗等補體結(jié)合試驗：

診斷Q熱柯可斯體中和試驗Neutralization：

抗O試驗酶聯(lián)免疫吸附試驗ELISAEnzymelinkedimmunosorbenassay211.Wellofmicrotitration(微量滴定)plateiscoatedwithspecificantibody2.SpecimencontainingantigenisaddedandtheantigencombineswiththeAb.3.Afterwashing,enzymelabelledAbisaddedwhichattachestotheantigen.4.Afterwashing,asubstrateisaddedwhichishydrolyzed(brokendown)bytheenzymetogivecolorchanges.ELISA22Section2細(xì)菌感染的特異性預(yù)防SpecificPreventionofBacteriainfection23一、人工主動免疫人工主動免疫是將疫苗及類毒素（抗原）接種于人體，使機體主動產(chǎn)生獲得性免疫力。是一種預(yù)防微生物感染的重要措施。主要用于預(yù)防。人工主動免疫疫苗類毒素24Inactivatedvaccines

Killedorganismsorbacteriaproducts.Theseantigensmayhoweverinduceweakand/orinappropriateresponse.

Immunememorymaybevariableorpoor,buttheyareusuallysafe.

第一代疫苗25死疫苗病原菌大量培養(yǎng)殺死,保留抗原性。多次接種,接種量大,反應(yīng)明顯,只激發(fā)體液免疫,不產(chǎn)生CTL。傷寒,霍亂,流腦,鉤體等。26AttenuatedVaccinesLivevaccinesconsistoforganismsthathavebeenattenuatedbygrowthinunfavourableconditions,forcingthemtomutatetheirgenes;thathavelostvirulencebutretainantigenicity.第一代疫苗27減毒活疫苗通過毒力變異獲得減毒或無毒株,培養(yǎng)后制成疫苗。宿主體內(nèi)繁殖,停留長,類似隱性感染。接種一次,用量小,副作用輕,效果好。不易保存,4℃,二周?；貜?fù)毒力,重新獲得致病性。BCG,鼠疫,炭疽。28Characteristic

LivingKilleddurationofimmunitylongershorterAbproduceIgA,IgGIgGcell-mediatedimmunityproduceyesweaklyornonereversiontovirulencepossiblenostabilityatroomtemperaturelowhighCharacteristicsofliveandkilledviralvaccines29亞單位疫苗SubunitVaccine利用微生物的某種表面結(jié)構(gòu)成分(表面抗原)制成不含有核酸、能誘發(fā)機體產(chǎn)生抗體的疫苗，稱為亞單位疫苗。第二代疫苗30基因工程疫苗GeneEngineeringVaccine

利用基因工程方法獲得帶有病原體保護(hù)性抗原表位的目的基因，將其導(dǎo)入原核或真核表達(dá)系統(tǒng)，表達(dá)該種保護(hù)性抗原，提純后研制成疫苗。

重組載體疫苗Recombinant

Vaccine

合成疫苗PeptideVaccine第二代疫苗31重組載體疫苗將抗原編碼基因轉(zhuǎn)入減毒的病毒或細(xì)菌制成疫苗,接種后在體內(nèi)繁殖表達(dá),似活疫苗。如以痘苗病毒為載體,用于甲肝,乙肝,麻疹疫苗的研制。第二代疫苗32核酸疫苗(DNA疫苗)將編碼產(chǎn)生抗原的基因重組到質(zhì)粒真核表達(dá)載體上,將重組的質(zhì)粒DNA直接注射給人體表達(dá)。優(yōu)點:抗原持續(xù)產(chǎn)生,免疫持久;體液和細(xì)胞免疫;對不同亞型病原有交叉保護(hù);將不同抗原基因構(gòu)建在同一質(zhì)粒-聯(lián)合免疫。問題:DAN整合激活癌基因;產(chǎn)生抗核抗體誘導(dǎo)自身免疫病。第三代疫苗33NakedDNAvaccinesGeneforantigenPlasmidRecombinantDNAMusclecell