细粒棘球绦虫和其他八年制

学名细粒棘球绦虫(Echinococcusgranulosus)

成虫寄生在狗、狼等食肉类动物体内

幼虫称棘球蚴，寄生在食草类有蹄动物体内

幼虫可寄生在人，引起棘球蚴病(echinococcosis,hydatiddisease)

E.granulosus,thespeciesresponsibleformostcasesofinfectionEchinococcosis,theinfectioniscausesalsoisknownascystichydatiddisease.Adultwormingastrointestinaltractofcarnivores,larvalstageinherbivorousanimalsandhumanbeing.Echinococcusgranulosus

Morphology

(1)成虫：绦虫中最细小的一种，2～7mm长。

(2)虫卵：与带绦虫卵相似

(3)棘球蚴(hydatidcyst)adult:small,consistsofscolex,neckandthreeproglottides,oneateachdevelopmentalstage:immature,matureandgravid.scolexcontainfoursuckers,hooks

egg:similarwithotherTaenia

smalltapeworm–2～7or3～7mmlong,consistsofscolex,neck,immatureproglottid,matureproglottid,andgravidproglottid

1.囊壁：(1)外层－角皮层：乳白色，无细胞结构，具保护囊内容物和渗透、吸收营养作用。(2)内层(germinallayer)：胚层，具生发作用，单细胞层，向外分泌角皮层，向内生成育囊(broodcapsule)、原头节(protoscolex)(3)囊内容物育囊：无角皮层子囊棘球砂游离于囊内物质，包括原头节、子囊、育囊，称棘球砂，一个原头节可以再形成棘球蚴，或入终宿主发育为成虫假囊壁：是炎症反应的宿主组织Hydatidcyst:Wheneggisingestedbyintermediatehost,includingperson,theliberatedembryopenetratestheintestinalwall,passesintothelymphaticsormesentericvenules,andiscarriedbythebloodstreamtovariouspartsofthebody.

Itgrowsslowly&requiresseveralyearsfordevelopment.afluid-filledbladder

containeddaughtercysts,broodcapsules

surroundedbyaprotectivecystwall,

laminatedmembranegerminallayer

ahydatidsandmayevolveinthefluidofoldercyst,broodcapsules,daughtercyst,protoscolex

laminatedmembranelaminatedmembranegerminallayergerminallayerbroodcapsuledaughtercysthydatidsandbroodcapsuleprotoscolex棘球蚴假囊壁棘球蚴角皮层胚层育囊子囊原头节adultsliveincaninesmallintestine 100s-1000sofwormsinupperhalfofsmallintestine release100sofinfectiveeggsinfeceslarvalstageinfection(sheep,cattle,pigs,horses&humans)

acquiredbyingestingembryonatedeggs

oncospherehatchesinsmallintestine

bloodstreamliverviaportalcirculation

otherorganscanbeinvaded(lung,brain&kidney)larvasurroundedbyhyalinemembrane

outernon-cellularstructure&innergerminallayer germinallayergivesriseto:

protoscolices(infectiousstagefordefinitivehost) moreoutermembranematerialcystdevelops,matures&fillswithfluid(monthstoyears)LifecycleLifecycleAdultwormofE.granulosusliveinthesmallintestineofadefinitivehostHumanaretheintermediatehost,carryingthehydatidcyst

SheeparethemostcommonintermediatehostforE.granulosus

Humaninfectionbeginsfollowingcontactwithcontaminateddogfeces

oncosphereshexacanthembryohydatidcysttissueofhumanAdultwormeggorgravidingestedhexacanthpenetrateintestinehydatidembryoenterveinsystemcystingestedbycarvivores

成虫

孕节

六钩蚴

棘球蚴污染牧草侵入血管人吞入六钩蚴棘球蚴牛羊吞入狼犬吞入人感染虫卵往往是下列情况：误食虫卵与狗接触而感染剪羊毛、接生羊羔、挤奶时受污染而感染Pathogenicity压迫和刺激

过敏和中毒破裂和细菌感染肝包虫病、肺包虫病、脑包虫病、骨包虫病并发症：囊肿破裂(胆囊、腹腔、胸腔）－－－继发性棘球蚴病、感染Hydatidcystcauseechinococcosis,orhydatidosisThedevelopmentofclinical&symptomsdependsonthesizeofthecystandtheorgansinvolved

symptomsarefromlarge,space-occupyinglesionoverallfatality~2%~50%ofhydatidcystsasymptomaticcystrupture(minorblunttrauma)leadstoanallergicreaction maybemild&limitedtourticaria maybeanaphylacticshockliveresenlarged uninvolvedpartofliverremainsnormal ruptureoflivercystsintobiliarytreelung bloodysputumcontainsprotoscolicesorhooklets ruptureintobronchialtreePathogenicityAhepaticlesionmaybeasymptomaticforaslongas75years(66%)

Hydatidcystsgrowfasterinlung(22%)&brain(2%)secondaryinfection

rupture(secondarycyst,allergicreaction)UnilocularhydatidcystinthelungNotepressureeffectsexertedbycystthatcrowdsanddestroyslungtissue

6inchunilocularhydatidcystthatkilleda7year-old-girlinColorado，USADiagnosis

1.询问病史2.免疫学3.Ｘ线、CＴMRI4.基因诊断

ahistoryofresidenceinanendemicarea,closecontactwithdog

X-ray,CT,MRISerologicaltest(skintest,IHA,ELISA)PCRismorespecificfordistinguishingdifferent

Echinococcusspecies

KeypointsPresumptivediagnosismaybebasedonhistory,radiographicstudies,orscansAdditionalsupportivedatamaybeacquiredfromimmunologictestsMicroscopicexaminationofhydatidcystfluidmayrevealthehydatidsandor,undercertaincircumstances,justthehookletsLight,fluorescence,andepi-fluorescencemicroscopycanbeusedtovisualizethehooklets;someapproacheswillrequirestaining,somewillnotEpidemiology

造成流行的原因：１.病犬、狼排泄物污染牧草，羊、牛吞入感染，人也可误食入。２.病牛、羊的内脏或病羊被狗或狼吞噬而感染。

３.虫卵抵抗力强。

foundinsheep-raisingarea

carnivoresaredefinitivehostsherbivoresareintermediatehosts

humaninfectionsresultingfromingestionofeggs

manisa‘deadendhost’fortheparasiteHumanscontracttheinfectionbyingestingeggsoftheparasiteinthefecesofthedefinitivehostContaminatedfoodorwateristhecommonrouteoftransmission,butdirectcontactwiththedefinitivehost,alsoisanimportantwaytoacquireinfection

Eggswithhighresistant

Prevention&control注意个人卫生，防止虫卵入预防犬感染治疗病人albendazole或手术

PAIR（PercutaneousAspiration,Injection,Re-aspiration)Surgicalremovalofthecystisindicatedinallcasesshowingsymptomsofthedisease

Themedicationmebendazole&albendazolehaveparticularlybeenusefulinsituationswherethehydatidcystwasinoperable

TheeducationprogramforinhabitantsinareasatriskfortransmissionoftheparasiteVaccineshaveeavailableforimmunizationoftheintermediatehost多房棘球绦虫(E.multilocularis)

幼虫期为多房棘球蚴，人因误食虫卵而感染，在人体引起严重的泡球蚴病，主要在肝脏，呈弥漫性生长、外生型，形成腔化囊泡。１－２年可使寄生器官被大小囊泡占据，犹如恶性肿瘤，需与恶性肿瘤鉴别。EndhostLifeCycleofEchinococcusmultilocularis

Alveolarhydatidcystinamouse-cystmetastasizesfromthelivertofillthebodycavity

Alveolarhydatidcystintheliver.Notethelaminatedlayer,germinallayer,protoscolices.Comparisonofunilocularandalveolarhydatidcysts

曼氏迭宫绦虫(Spirometramansoni)

成虫寄生在猫狗小肠，偶尔寄生人体致曼氏迭宫绦虫病。幼虫则为裂头蚴(sparganum)，可寄生在蛇、蛙体，也可寄生人体致病－裂头蚴病(sparganosis)。Morethan300humancaseshavebeenreportedintheworldliteratureMajorendemicareasareChina,Japan,Korea,Vietnam,ThailandandotherSoutheastAsiancountries.OnHainanIsland,itisstillcommonpracticetoapplyrawfrogfleshasapoulticetotheeyeofpatientswithhighfever.一、形态成虫60-100cm，成节、孕节结构相似。裂头蚴长带形，白色，约300×0.7mm

虫卵纺锤形，两端稍尖，有卵盖，卵壳内含卵黄细胞和一个卵细胞。二、生活史需三个宿主终宿主：猫,狗第一中间宿主：剑水蚤第二中间宿主：蛙、蛇、鸟、猪为转续宿主人可作转续宿主、中间宿主、终宿主

成虫卵钩球蚴原尾蚴裂头蚴

人既可被裂头蚴寄生，也可被成虫寄生。

入水2-5W剑水蚤吞入穿入血腔猫犬吞入剑水蚤三、致病裂头蚴病人感染的方式：

1.饮用生水或游泳时误饮湖水。

2.局部敷贴生蛙肉。

3.吞食生或半熟蛙、蛇肉。

常寄生于眼(30-45%)、皮下肌肉(31-37%)、

脑（2.3-3.1%)引起嗜酸性肉芽肿－局部肿

胀、疼痛，游走性肿块。四、诊断

1.询问病史

2.活检

3.免疫学诊断，ELISA五、流行和防治分布广，主要流行区为中国、日本、越南、泰国、东南亚国家。防治：１.卫生宣教２.裂头蚴－手术３.成虫－吡喹酮TaeniasoliumandTaeniasaginataproglottidscanbedifferentiatedby孕节的子宫分支B.子宫孔的位置C.孕节的形态D.孕节的颜色E.孕节的长度Whichisnotadiseaseoftapeworms?A.中枢囊尾蚴病

B.贫血C.胆道梗阻

D.体重减轻E.腹痛Whichtapewormegginhumanstoolmightbeseenbymicroscopy?A.ClonorchissinensisB.TaeniasoliumC.EchinococcusgranulosusD.SchistosomahaematobiumE.FasiolopsisbuskiQuiz:Concerninghookworminfection,somethingincorrectdescriptionasfollow:A.HookworminfectioncancauseanemiaB.HookworminfectionisacquiredbyhumanwhenfilariformlarvaepenetrateC.HookworminfectioncanbecausedbytwokindofhookwormD.HookworminfectioncanbediagnosisbyfindingthetrophozoiteinthestoolE.HookworminfectioncanbecontrolbyavoidingcontactwithinfectivesoilWhichoffollowingparasitecouldbecausedbyselfinfection：

A．TaeniasoliumB．AscarislumbricoidesC．EnterobiusvermicularisD．LeishmaniadonovaniE．Paragonimuswesternamni1.WhichnematodedoesnotleavetheGItrackduringinfection?AscarislumbricoidesTrichinellaspiralisNecatoramericanusWuchereria