大二下学习寄生虫课件

THELUNGFLUKES

(pulmonaryflukes)

Professor:JianpingChenSichuanUniversityTHELUNGFLUKES

Species.Atleast28specieshavebeenidentified,8speciesareinfectedwithhuman

Paragonimuswestermani(kerbert,1978)Braun,1899Pagumogonimusskrjabini(Chen,1959)Chen,1963ParagnoimusmexicanusP.kellicotti

ParagonimuswestermaniinChina

PagumogonimusskrjabnionlyinChina

MorphologicalfeatureCommonfeatureofadultwormsMorphologydifferencebetween2speciesEggSize:0.8～1.6cm×0.4～0.8cm×0.3～0.5cmreddishbrowntegumentisprovidedwithspinesOralsuckerandventralsuckeraresubsequent.Thelatterisanteriortotheequator.Theexcretorybladderislongertwotestsaresituatednearlyside-by-side,betweentheventralsuckerandtheposteriorend.Uterusisatightlycoiledorganonthesideoppositeoftheovary.AdultandeggofParagonimuswestermani

Morphologydifferencebetween2species

P.wespermaniP.skrjabini1.shape2.positionofventralsucker

3.ovaryellipsoidanteriortotheequator

5~6branchesslender1/3fromtheanteriorend

morebranchesadultwormsofParagonimuswestermaniandPagumogonimusskrjabni

Egg

80to120umby48to60um,operculum,shouldergolden-brown

TheeggofParagonimuswestermani

nomorphologydifferenceofeggbetween2species

AdultandeggofPagumogonimusskrjabni

PagumogonimusskrjabniRedia,cercariaandmetacercariaLifecycle

Theprocessofdevelopment

Waysoftheinfection

WayofthemigrationinhumanReservoirhost:TheprocessofdevelopmentAdult:inthelungoffinalhosteggsinsputumorfeceseggs:ondischargefromthefinalhostbody,theeggsrequireatleast2weeksforcompleteembryointhewater.miracidium:whentheyhatch,themiracidiumescapeandfreeswimming,penetratemolluskhost(Mallaniidsnails).sporocyst:

Withinthesnailduringaperiodofseveralweeks,asporocystandtworediagenerationareproduced,followedbythedevelopmentofcercaria.

sporocystrediaIrediaIICercariaAsexualgenerationEncystedmetacercaria:

inintermediatehostAfterleavingthesnail,Cercariainvadethetissuesinthefresh-watercrabsorthecrayfish

Adult:metacercariaareeatenbyhumanandotherfinalhost(dog,cat).

Waysoftheinfection

foodtypesdrunkencrabcrabsoupfolkremedyTheroleofparatenichost

miyazaky(1978)：100personinfectedbyeatenrawwildboarmeatinfectionresultsfromtheingestionofraworin-sufficientlycookedcrayfishorfresh-watercrabs,inwhichtheencystedmetacercariastageoccurs.Thewayofacquiringinfection

1)ingestingraworuncookedcraborcrayfishcontainingmetacercariae2)ingestingthemeatofaparatenichostcontainingimmatureflukes3)drinkingwatercontainingmetacercariaeorcercariaeHalf-cookedandrawcrabWayofthemigrationinhuman

Aftereating,metacercariaexcystintheintestine,penetrateintotheperitonealcavity,andthroughthediaphragmandpleuraintothelungs.wormsareencapsulatedinthetissues,adjacenttothebronchi.Theygrowtomaturityin6weeks.Ruptureofthecystcapsuleintoabronchioleleadstodischargesoftheeggs,butnotoftheparasite,Chronicinfectionmaypersistfor5~6(20)years.

normalroutelung

subcutaneoustissuesabnormalroutebraintissues

musculartissue

Reservoirhostfelines:tigers,lions,leopardscanines:dogs,foxes,wolvesothermammals:pig,wildboar,andothersthateatfresh-watercrabsandcrayfish.Humanareaccidentalhostoftheseparasite.

Human

isdefinitivehostof

Paragonimuswestermani,andisparatenichostof

Pagumogonimusskrjabni

Pathogenesis

1.Acutestage,larvaemigrantandectopicparasite,2.Chronicstage,adult(1)Stageofabscess

(2)Encapsulatedstage

(3)Formsoffibrousnodule

Stageofabscesswormsproduceslocalhemorrhageandleukocyticinfiltrationinthetissues.Whenthewormsparssitesinthelungeorinectopicfoci,moretissuereactionoccur.Abscessusuallydeveloparoundtheworm.

Encapsulatedstage

theencapsulatedinthelungorectopicfoci.Aleukocyticinfiltratefromaroundtheparasite,andfibroustissuesurroundsthewormstoformacystwall.Communicationofthecystwiththerespiratorytree.Ruptureofthecystgointoadjacentbronchioles,Sputumcontainingeggs,hemorrhage,charcot-leydencrystals.

Formsoffibrousnodulewormsdieorescape,contentsareabsorbed,ordischarge,eggsarecalcification.3phasesofpathologicalchangescanpersistinoneorgansymptomsPulmonarytype:fever,rustysputum,hemoptysis,cough,chestpain,eosTheclinicalsymptomsoftenlikespulmonarytuberculosis.braintype:Whentheparasitearelocatedinthebrain,signsandsymptomsofaspaceoccupyinglesionusuallydevelop.cutaneoustype:migrantnodulesCerebral

type:Thesymptomsoftheacutestagearefever,headache,nausea,vomiting,visualdisturbances,andparalysis.

Livetype:Disorderofliverfunction,largeliver,andliverpainarecommonsymptomsofliverparagonimiasis.Differenceofpathogenesis

andclinicalfortwospecies.

P.Westermani:PulmonarytypeP.Skrjabini:LesionofectopicsitesLarvaemigrantssubcutaneousnodulesbrainsignsandsymptomshepaticdamagesAdultlungflukesLunginfectedwithParagonimuswestermani

Humanpatientwithparagonimiasis（并殖/肺吸虫病人）brainsignsandsymptomslarveinbrainofPatientsEyeparagonimiasis:

DiagnosisHistoryofeatingrowcrayfishorfresh-watercrabs.detectingeggsinsputumorfeces.biopsy10%NaOHimmunologicaldiagnosisId(intradermaltest)CIEPELISALung

biopsy

ofpulmonaryparagonimiasis

larvaeEpidemiology

Distribution:worldwidein.AsiaendemicareasincludingChina,Japan,Korea,Laos,thePhilippines,andThailand;inAfrica,theCameroon,theCongoValley,Gambia,andNigeriainSouthandCentralAmerica,Colombia,CostaRica,Mexico,andPeru.Transmission:

Inmostareas,thediseaseisprincipallyoneofthelocalcrab-eatingmammals,andhumansenterintothelifecycleandinfectsaccidentally.NortheastChina：crayfishSouthChina：crab

Threemainfociofthedisease:inAsiaendemicareasincludingChina,Japan,Korea,Laos,thePhilippines,andThailand;inAfrica,theCameroon,theCongoValley,Gambia,andNigeriainSouthandCentralAmerica,Colombia,CostaRica,Mexico,andPeru.。Distribution

Inourcountry,Paragonimiasisusedtobein23provinces,includingShandong,Jiangsu,Anfei,Jiangxi,Zhejiang,Fujian,Guangdong,Henan,Hubei,Hunan,Sichuan,Guizhou,Guangxi,Yunan,Hainan,Taiwan,Gansu,Shanxi,Hebei,Liaoning,Jilin,Heilongjiangetc.Prevention

Abstainingfromeatingraworinadequatecookedcraborcrayfish.Abstainingfromcontaminatingfingerswiththemetacercariawhilecooking.

Treatment

Praziquantel:25mg/kg,Tid,2day.Bithionol:15~25mg/kg,Tid,10~15day.

Casereport患者，男，35岁。主诉：反复胸痛、胸闷、咳嗽、咳痰8个月，近3个月加重。病史：8个月前曾出现畏寒、发热、双侧胸痛、咳嗽、食欲减退症状。胸部X片：左下肺有结节状阴影，怀疑肺转移癌，经住院对症和化疗2个月好转。近3个月胸痛、胸闷、咳嗽、咳痰加重，左上肺出现片状模糊阴影，双侧胸腔少量积液，以结核病住院治疗3个月，未见好转，遂转院就诊。查体：T37.6℃，P98次／min，R22次／min。一般情况尚好，神清，唇微绀，右腰部皮下触及一个2.0cm×3.5cm包块，中等硬度无压痛，皮肤表面无红肿。心脏无异常，左肺呼吸音略减弱，左下肺可闻及少量湿罗音。腹部（-）。血常规：WBC12.9×109／L，N45%，EOS23%。肝功能正常。痰抗酸杆菌（-）。胸部X片显示：左上肺野见斑片状阴影，左下肺有条索状纹理增粗。双侧少量胸腔积液，胸膜增厚。诊断及治疗过程：以肺炎和胸膜炎收入院。在对症治疗的同时，根据EOS增高的特点，怀疑感染了寄生虫病，追问病史，患者述3年前曾多次食烤蝲蛄。卫氏并殖吸虫病免疫学检查：皮试（+），ELISA（+）。卫氏并殖吸虫卵检查：痰检（-），粪检（-）。诊断：卫氏并殖吸虫病。治疗：用吡喹酮治疗3天，同时继续对症治疗，2周后患者症状、体征基本恢复正常。

相关问题提示：病例中哪些指标支持卫氏并殖吸虫病的诊断?分析本患者胸部X片的改变与病理过程的关系?分析本患者的临床分型属于哪几种?未查到虫卵的原因可能有哪些?FACIOLOPSISBUSKI

Morphologicalfeature

AdultwormThelargestintestinalfluke,2-7.5by0.8-2cm,ovoid,pinkishTheoralsuckerissmaller,theventralsuckerisvarylargerTestsarehighlybranched,occupyalmosttheposteriortwo-thirdsofthebody.AdultAdultofFasciolopsis

buski

EggThelargestoneintheeggsofthetrematode.130~140by80~85cm.smalloperculum,thinshell,TheeggofFasciolopsisbuski

MetacercariaandCercariaLifecycle

Adultwormsliveattachedtothebowelwallofduodenum,jejunum.

Eggs:hewater3-7week

miracidium

Inthesnailhost(Planorbiidsnails)

sporocystrediaIrediaIICercariaMetacercaria

Encystedonthefreshwatervegetation-waterchestnut,watercaltrop．Thewayofinfectionwiththemanconsumedraworpeeledwithteeth.reservoirhost:pigs,dogs,rabbitClinicalaspect

Attachmentofthelargewormstothemucosaofthebowelcauseslocalinflammationandulceration,sometimeaccompaniedbyhemorrhage.Mostoftheinfectionsareligh