溶组织内阿米巴课件.ppt

溶组织内阿米巴课溶组织内阿米巴课件件To be defined as unicellular animals；The single cell relatively has complex metabolic activities such as digestion,reproduction,respiration,excretion,etc.10,000 species of parasitic protozoa.Important human parasitic protozoa:Malaria parasites,Leishmania,Entamoeba histolytica,Trichomonas vaginalis,Trypanosoma and Toxoplasma gondiiProtozoa：MorphologyMorphology1、diversity:round,ellipse,pear shape,irregular 2、Size：very smallRange in size from 2 to more than 200m1.Plasma membrane:2.Cytoplasm3.NucleiStructureStructure1.Plasma membrane:2.Cytoplasm3.Nuclei1.Plasma membrane:a unit membraneStructureStructure1.Plasma membrane:2.Cytoplasm3.Nuclei2.Cytoplasm1)ectoplasm:the outer transparent layer.function:protection,locomotion,sensation.2)endoplasm:the inner granular layer,containing vacuoles and organelles.function:metabolism,nutrition,reproduction.3)organelles:1.Plasma membrane:2Cytoplasm3.Nuclei2.Cytoplasm3)organelles:A.membrane organelles:Mitochondria,Endoplasmic reticulum,Golgi bodies,etc.B.locomotor organelles:pseudopodia,flagella,cilia.StructureStructure1.Plasma membrane:2.Cytoplasm3.Nuclei3.Nuclei1)compact nucleus：seldom2)vesicular nucleus：commonNuclear membraneA karyosomeChromatin granulesStructureStructurePhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:1.Locomotion:1)flagella,2)cilia,3)pseudopodia,4)and no specific locomotion organelles.Trichomonas vaginalisPhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:1.Locomotion:1)flagella,2)cilia,3)pseudopodia,4)and no specific locomotion organelles.Balantidium coliPhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:1.Locomotion:1)flagella,2)cilia,3)pseudopodia,4)and no specific locomotion organelles.Entamoeba histolyticaPhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:1.Locomotion:1)flagella,2)cilia,3)pseudopodia,4)and no specific locomotion organelles.plasmodiumPhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:2.Nutrition 1)permeation:by diffusion or by active transport 2)pinocytosis and phagocytosis:PhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:3.Reproduction 1)asexual reproduction 2)sexual reproductionPhysiologyPhysiologyPhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:3.Reproduction 1)asexual reproduction binary fission:multiple fission:budding reproduction:PhysiologyPhysiology1.Locomotion:2.Nutrition:3.Reproduction:4.Metabolism:5.Excretion:3.Reproduction 1)asexual reproduction 2)sexual reproduction gametogony:conjugation:zygote Classification of protozoa Classification of protozoaclasslocomotory organellesreproductionspecies nameZoomastigophoraflagellabinary fissionTrichomonas vaginalis Loboseapseudopodiabinary fissionEntamoeba histolytica Sporozoeano specific locomotionmultiple fission,gametogonyPlasmodium vivax Kinetofrag-Minophoreaciliabinary fission,syngamyBalantidium coli Entamoeba histolytica E.histolytica lives within the large intestine.Trophozoites can invade the colonic epithelium and produce ulcers and dysentery.This invasive disease can become progressively worse and lead to extraintestinal amebiasis.MalariaSchistosomiasisAmoebiasisPrevalence of amoebiasis400 million200 million50 million Morphology 1.Trophozoite pseudopodiumnucleuserythrocyteChromatic granuleskaryosomeAchromatic fibrils Trophozoite picture by scanning electron microscope2.Cyst Stained by Iron hematoxylinchromatoid bodyglycogen vacuole2.CystStained by IodineMature cyststrophozoitestrophozoitescystLife cycleLife cycleBe ingestedBe passed in the formed stoolIn the lower small intestine,excystationIn the lower colonInvade the colonic walltrophozoitestrophozoites trophozoitesBe passed in the dysenteric fecesGo into the circulatory system,and spread to liver,lung,brain,etctrophozoites trophozoitesSummary of life cycleInfective stage:mature cyst.Infection occurs by the ingestion of cysts in contaminated water,food,or by the fecal-oral route(hands or fomites).Cysts are seen in the formed stool.Trophozoites are seen in the dysenteric feces and liver,lung,brain,etcPathogenesis and Manifestation.10%infected with E.histolytica will develop invasive amebiasis.?Factors that determine invasion of amebas:1.Parasite factors A The number of amebas ingested.B The pathogenic capacity of the parasite strain2.Host factors3.Bacteria factorsPossible pathogenic mechanismPossible pathogenic mechanismparasite factors1 resistance to host response(eg,complement resistance)to resistance to complement mediated lysis to degrade secretory IgA to suppress T-cell responses to kill neutrophils and other immune effector cells in a contact dependent manner.(lysis of neutrophils could release toxic products which contribute to the destruction of host tissue)Possible pathogenic mechanism2Adherence properties mediated by surface lectin known as Gal/Gal NAC(半乳糖半乳糖/乙酰氨基半乳糖凝集素乙酰氨基半乳糖凝集素)3 Cytolytic properties(adherence+amoebapore)4 Secrete cytotoxins(cysteine proteinases)and kill target cell in the intestinal mucosaparasite factors:Host factors Possible pathogenic mechanism Host factors in amoebiasis may be non-immune defense mechanism and specific immunity.Suitable enteric bacteria can enhance amebic growth.Bacteria factorsAn experiment with catsGroup A Group BMature cysts Mature cysts+Bacillus aerogenesLower morbilityHigher morbilityGentle symptomSerious symptomnon-invasive .ameba colony on mucosa surface .asymptomatic cyst passer .non-dysenteric diarrhea Amebiasis Progressioninvasive .necrosis of mucosa ulcer .dysentery .hematophagous trophozoites Mucus layerMuscle layerSerous layerSubmucosalumen.ulcer enlargement peritonitis .occasional ameboma.metastasis extraintestinal amebiasis metastasis extraintestinal amebiasis .via blood-stream or direct extension .primarily liver amebic abscess .other sites infrequent .ameba-free stools common Amebiasis ProgressionAmebiasis Progressioninvasive pathogenesis&manifestation.ulcer enlargement peritonitis.occasional ameboma.necrosis of mucosa ulcer .dysentery .hematophagous trophozoitesThe places that amebic ulcers occur usuallyCaecum87%Ascending colon 57%Sigmoid colon 33%Rectum37%Pathogenesis.metastasis extraintestinal amebiasis .via blood-stream or direct extension .primarily liver amebic abscess .other sites infrequent .ameba-free stools common Amebic liver abscessLaboratory diagnosis.Stool examination.Sigmoidoscopy.Immunological diagnosis.Imaging.Abscess aspiration Formed stoolsA direct smear stained by Iodine/Iron hematoxylin for cyst.Compare:Laboratory diagnosis.Stool examination Formed stoolsA direct smear stained by Iodine/Iron hematoxylin for cyst.diarrheic stoolsA direct saline smear for motile trophozoites.1)fresh stools 2)in time 3)keep warm in cold weatherLaboratory diagnosis.Stool examination.Sigmoidoscopy Lesions,aspirate,biopsyLaboratory diagnosis.Stool examination.Sigmoidoscopy.Immunological diagnosis Fluorescent antibody The indirect hemagglutination test Indirect fluorescent antibody testLaboratory diagnosis.Stool examination.Sigmoidoscopy.Immunological diagnosis.Imaging CT,MRI,ultrasound,X-rayLaboratory diagnosis.Stool examination.Sigmoidoscopy.Immunological diagnosis.Imaging.Abscess aspiration Only select casesEpidemiology Distributionall populations throughout the world.the tropics and subtropica than in cooler climates.insanitary communities of temperate and subarctic areas Epidemiology DistributionThe incidence is estimated that up to 10%of the worlds population may be infected with either E.histolytica or E.dispar and in many tropical countries the prevalence may approach 50%.There are an estimated 50 million cases of amebiasis per year and up 50 to 100 thousand deaths among them.Epidemiology Epidemic factors1.Reservoir of infection:asymptomatic or only mildly afflicted.2.The cysts are relatively resistant to bad condition of environment.3.Disposal of human feces is inadequate,and lead to contamination of food or water with fecal material.4.The housefly and the cockroach is an importance factor in the transmission of the disease.Prophylaxis and Treatment1.Amebiasis treatment:Asymptomatic:Iodoquinol,Paromomycin,or Diloxanide furoate Nondysenteric,Dysenteric,or Extraintestinal:Metronidazole(甲硝唑甲硝唑,灭滴灵灭滴灵),or Tinidazole+lumenal agent Prophylaxis and Treatment1.Amebiasis treatment:2.Sanitary disposal of feces.3.Protecting water supplies from contamination.4.Health education in regard to improving personal hygiene,drinking boiled water,hand washing5.Killing the housefly and the cockroach.Entamoeba dispar E.histolytica and E.dispar are actually two morphologically identical species.(E.histolytica and E.dispar cannot be distinguished on morphological criteria,but DNA sequence and isoenzyme pattern.)E.dispar is non-pathogenic.(E.histolytica is pathogenic.)To cause human disease:.Primary amebic meningoencephalitis(PAM).Chronic granulomatous amebic encephalitis(GAE).Amebic keratitis Pathogenic free-living amebae NaegleriaAcanthamoeba Pathogenic free-living amebaeNaegleriaNaegleria The portal of entry:the trophozoites enter the nasal cavity,replicating,and then migrate along the olfactory nerves into the brain and CNS.Pathogenic free-living amebaeAcanthamoeba The portal of entry:unknown but believed to the either the lungs,skin or eyes.Presumably the trophozoites disseminate by a hematogenous route.Pathogenic free-living amebaeEntamoebaEntamoebaEntamoeba histolyticaEntamoeba histolyticaEntamoeba coliEntamoeba coliEntamoeba disparEntamoeba disparNaegleriaNaegleriaAcanthamoebaAcanthamoebaMature cyststrophozoitestrophozoitescystLife cycleLife cycleBe ingestedBe passed in the formed stoolIn the lower small intestine,excystationIn the lower colonInvade the colonic walltrophozoitestrophozoites trophozoitesBe passed in the dysenteric fecesGo into the circulatory system,and spread to liver,lung,brain,etctrophozoites trophozoitesextraintestinal amoebiasisintestinal amoebiasis病史摘要：病史摘要：患者，男，患者，男，48岁。反复腹泻半年，近岁。反复腹泻半年，近20余日来大便呈红色果酱样，大便余日来大便呈红色果酱样，大便次数明显增多每日可达数十次。体检：体温次数明显增多，每日可达数十次。体检：体温38，一般情况较差，精神萎靡，一般情况较差，精神萎靡，下腹部压痛阳性，肝大，表面不光滑，有波动感。腹部下腹部压痛阳性，肝大，表面不光滑，有波动感。腹部X线片见横膈抬高，以线片见横膈抬高，以右侧为甚。患者于拍片后下楼时，不慎摔倒，突然面色苍白，四肢厥冷，经抢右侧为甚。患者于拍片后下楼时，不慎摔倒，突然面色苍白，四肢厥冷，经抢救无效，救无效，1小时后死亡。尸检：心包显著扩大，小时后死亡。尸检：心包显著扩大，18cmX17cmX12cm，内含暗红，内含暗红色液体约色液体约1500ml。肝重。肝重870g，左叶中部可见一，左叶中部可见一12cmX9cmX8cm单房性囊腔，单房性囊腔，内含咖啡色黏稠液体，有似烂鱼肉的腐臭味。囊腔膈面肝组织及膈肌菲薄，与内含咖啡色黏稠液体，有似烂鱼肉的腐臭味。囊腔膈面肝组织及膈肌菲薄，与心尖部心包紧密粘连，并见一通向心包腔的穿孔心尖部心包紧密粘连，并见一通向心包腔的穿孔(直径直径1cm)。回肠末端有数个溃。回肠末端有数个溃疡，形状、大小不一，最大者疡，形状、大小不一，最大者6cm，边缘呈潜行性。腹腔内含草黄，边缘呈潜行性。腹腔内含草黄*色液体约色液体约700ml，肠系膜淋巴结普遍肿大，质软。镜检发现于肝囊腔及肠溃疡周边部，肠系膜淋巴结普遍肿大，质软。镜检发现于肝囊腔及肠溃疡周边部查见阿米巴滋养体。查见阿米巴滋养体。分析：分析：1 1、根据临床表现、实验室检查及尸体解、根据临床表现、实验室检查及尸体解剖检查结果，做出病理诊断并说明诊断剖检查结果，做出病理诊断并说明诊断依据。依据。2 2、试分析本病例的发生、发展经过。、试分析本病例的发生、发展经过。3 3、本例死亡原因是什么。、本例死亡原因是什么。1 1、阿米巴病：肠阿米巴、肝阿米巴脓肿、阿米巴性心包炎、阿米巴病：肠阿米巴、肝阿米巴脓肿、阿米巴性心包炎(心包积液心包积液)、阿米巴性腹膜炎、阿米巴性腹膜炎(腹腔积液腹腔积液)。依据：红色果酱。依据：红色果酱样大便、回肠末端溃疡；横膈抬高、肝内有含有咖啡色黏样大便、回肠末端溃疡；横膈抬高、肝内有含有咖啡色黏稠液体的囊腔；心包扩大、含暗红色液体、肝囊腔有一向稠液体的囊腔；心包扩大、含暗红色液体、肝囊腔有一向心包腔的穿孔；腹腔积液；镜检查见阿米巴滋养体。心包腔的穿孔；腹腔积液；镜检查见阿米巴滋养体。2 2、成熟包囊被食入后在肠液作用下发育为小滋养体、成熟包囊被食入后在肠液作用下发育为小滋养体侵入肠侵入肠粘膜溶解破坏组织粘膜溶解破坏组织肠阿米巴肠阿米巴滋养体经肠壁小静脉随门滋养体经肠壁小静脉随门静脉入肝静脉入肝溶解破坏组织形成肝阿米巴溶解破坏组织形成肝阿米巴周围扩散周围扩散膈下膈下脓肿、脓胸、肺脓肿、肝膈肺联合脓肿、阿米巴性心包炎、脓肿、脓胸、肺脓肿、肝膈肺联合脓肿、阿米巴性心包炎、阿米巴性腹膜炎等。阿米巴性腹膜炎等。3 3、可能的死亡原因是肝破裂出血。、可能的死亡原因是肝破裂出血。参考答案参考答案