《基础医学各论3》资料：18传染病-3

1、Chapter 19 Human Parasitosis,阿米巴病 血吸虫病,Amoebiasis 阿米巴病,Amoebiasis is a human parasitosis mostly caused by entamoeba histolytica 溶组织内阿米巴 Intestinal amoebiasis Amoebic liver abscess Amoebic pulmonary abscess Amoebic cerebral abscess,Intestinal amoebiasis 肠阿米巴,Pathogenesis 包囊体-滋养体 mechanical injury and

2、 phagocytosis Contact lysis 接触溶解 Cyto-toxic 细胞毒素 Bacterial 协同 Susceptibility 易感性-男性 Immune suppression and Immune escape 免疫抑制逃避-长期存在,Morphology,Location: firstly involves cecum盲肠, colon ascendens 升结肠, secondly sigmoid colon and rectum, in some cases involve the whole colon and inferior segment of sm

3、all intestine flask shaped ulcer 烧瓶状溃疡 Acute phase Chronic phase,Acute Phase,Gross Yellowish spotty necrosis/ulcer Swelling, edema and bleeding zone Map necrosis, filled with yellowish-brown mucous purulence substance Histology liquefaction necrosis 液化性坏死, only minor inflammation nearby Large amoebi

4、c trophozoite can be seen in the juncture of necrosis and normal tissue vacant space around trophozoite,Chronic Phase,Mixture of fresh and old lesion Necrosis, ulcer with proliferation epithelial proliferation and polyp Fibrous proliferation, scar, thicken and harden of the enteric wall, stricture o

5、f enteric cavity 阿米巴肿 ameoboma p486,Amoebic liver abscess,Amoeba trophozoite penetrate the vein of enteric wallvena mesentericaVena portalis hepatisliver Gross Single, the size of abscess varied The fruit jam substance consists of liquification, oboslete bleeding 果酱样大便 Abscess wall consists of the c

6、onnect tissue of vena portalis hepatis, like old cotton 破絮状 Minor inflammation around the abscess Histology Pus cells, necrosis Amoeba trophozoite around the wall of abscess,Amoebic pulmonary abscess,Rare, developed from Amoebic liver abscess, which penetrate the disphragmatic muscle Most commonly s

7、ingle, often located lower lobe of the right lung, may connect with liver abscess The liquification necrosis may be discarded, and the pulmonary cavity formed Dark brown purulent expectoration, 脓性痰Amoeba trophozoite may be found,Schistosomiasis 血吸虫病 p487,Schistosomiasis infects approximately 200 mil

8、lion persons and kills approximately 280,000 annually. Most of the mortality comes from hepatic granulomas and fibrosis. In addition, Schistosoma haematobium, found in Africa, causes hematuria and granulomatous disease of the bladder, resulting in chronic obstructive uropathy.,Achistosomiasis 血吸虫病,E

9、tiology and route of infection,cercarial dermatitis 尾幼性皮炎、稻田皮炎、游泳痒 童虫引起肺损伤 Damage by 成虫：静脉内膜炎及其周围炎、血栓形成、贫血、嗜酸性粒细胞增多、肝脾肿大 Damage by egg Damage by the antigens and immune compounds in circulation 肾脏损害,Pathogenesis and morphology,Morphology of organs - Colon,Acute phase 血吸虫病痢疾 Congestion, edema, gray-y

10、ellowish or yellow-whitish nodule, 0.54mm in diameter The nodule may break ulcer The eggs in the ulcer may be discarded and become pollution 污染源 Chronic phase Eggs, fibrous proliferation, scaring Ulcer, necrosis, narrowing or obstruction of the enteric cavity 肠腔狭窄,Morphology of organs- Liver,Acute p

11、hase 急性虫卵结节-嗜酸性脓肿 Swelling of liver, not smooth in the surface, numerous millet or mung bean sized yellow or whitish nodules in the surface or the cutting surface Histologically, the acute egg tubercle mainly located around portal area, the atrophy, degeneration and focal necrosis of hepatocytes can

12、 be seen Chronic phase 慢性虫卵结节-假结核结节 Eggs, fibrous proliferation, calcification Fibrous proliferation around the portal area, thicken of the wall of veins, thrombosis Stem live liver cirrhosis Portal hypertension and relative symptoms,Morphology. In mild S. mansoni or S. japonicum infections, white,

13、pinhead-sized granulomas are scattered throughout the gut and liver. At the center of the granuloma is the schistosome egg, which contains a miracidium; this degenerates over time and calcifies. The granulomas are composed of macrophages, lymphocytes, neutrophils, and eosinophils; the last-mentioned

14、 are distinctive for helminth infections. The liver is darkened by regurgitated heme-derived pigments from the schistosome gut, which, like malaria pigments, are iron-negative and accumulate in Kupffer cells and splenic macrophages.,Schistosoma mansoni granuloma with a miracidium-containing egg (cen

15、ter) and numerous, adjacent, scattered eosinophils.,In severe S. mansoni or S. japonicum infections, inflammatory patches or pseudopolyps may form in the colon. The surface of the liver is bumpy, whereas cut surfaces reveal granulomas and a widespread fibrous portal enlargement without distortion of

16、 the intervening parenchyma by regenerative nodules. Because these fibrous triads resemble the stem of a clay pipe, the lesion is named pipe-stem fibrosis. Many of these portal triads lack a vein lumen, causing presinusoidal portal hypertension and severe congestive splenomegaly, esophageal varices,

17、 and ascites. 门脉高压重，肝功能损害轻,Schistosome eggs, diverted to the lung through portal collaterals, may produce granulomatous pulmonary arteritis with intimal hyperplasia, progressive arterial obstruction, and ultimately heart failure (cor pulmonale). 肺心病 On histologic examination, arteries in the lungs s

18、how disruption of the elastica layer by granulomas and scars, luminal organizing thrombi, and angiomatoid lesions similar to those of idiopathic pulmonary hypertension. Patients with hepatosplenic schistosomiasis also have an increased frequency of mesangioproliferative or membranous glomerulopathy,

19、 in which glomeruli contain deposits of immunoglobulin and complement but rarely schistosome antigen.,Pipe-stem fibrosis of the liver due to chronic Schistosoma japonicum infection 干线型肝硬变,Morphology of organs,Ectopic Lung Brain 急性脑炎、癫痫 Others 肾、胰腺、胆囊、心脏、膀胱、子宫 Schistosoma dwarfism 血吸虫侏儒症 Acute schist

20、osomiasis 急性血吸虫病,Amoebiasis 小结,Entamoeba histolytica Intestinal Amoebiasis Amoebic dysentery Contact lysis Enterotoxin,Acute change Flask shaped ulcer Chronic change Amoeboma,Extraintestinal amoebiasis,Amoebic liver abscess Amoebic plumonary abscess Amoebic cerebral abscess,血吸虫病小结,Cercarial dermatit

21、is Eosinophilic abscess Pseudotubercle Pipe stem cirrhosis Ectopic parasitism Schistosoma dwarfism Acute schistosomiasis,Pathogens: 病原 Pyogenic meningitis: 化脓性脑膜炎 Meningococci, H influenza, Pneumococci, Streptococci, Staphylococci, E Coli Granulomatous meningitis: 肉芽肿性脑膜炎 T.B.mycobacterium, Fungi Ly

22、mphocytic meningitis: 淋巴细胞性脑膜炎 viruses, spirochetes,Meningitis 脑膜炎 401,MENINGITIS,Meningitis refers to an inflammatory process of the leptomeninges and CSF within the subarachnoid space. Meningoencephalitis refers to inflammation of the meninges and brain parenchyma. 脑膜脑炎 Meningitis is usually cause

23、d by an infection, but chemical meningitis may also occur in response to a nonbacterial irritant introduced into the subarachnoid space. 化学性 Infiltration of the subarachnoid space by carcinoma is referred to as meningeal carcinomatosis (sometimes called carcinomatous meningitis) and by lymphoma as m

24、eningeal lymphomatosis. 瘤性 Infectious meningitis is broadly classified into acute pyogenic (usually bacterial meningitis), aseptic (usually acute viral meningitis), and chronic (usually tuberculous, spirochetal, or cryptococcal) on the basis of the characteristics of inflammatory exudate on CSF exam

25、ination and the clinical evolution of the illness.,Epidemic Meningococcic Meningitis(流行性脑膜炎双球菌性脑膜炎),Pathogen: meningococci, epidemic seasons : Winter & Spring Bacteria spread by air (sneeze and spray), located at nasopharyx, most are bacteria carrier (15% population, in epidemic season:7080%) Victim

26、s are children, most younger than 10yrs old Basic changes：acute purulent 化脓性 inflammation (Leptomeninge & CSF ) Clinical symptoms & signs: fever,headache, vomiting, petechia & ecchymosis on the skin & mucosa, meningeal irrigative signs, shock in severe cases Temporary immunity after recovery,Meningi

27、tis,Pathogen: meningococci, endotoxin and capsule are pathogenic Route of infection:,Spray from carrier,Mucosa of nasopharyx,Blood (septicemia or bacteremia),leptomeniges,meningitis,Usually 5%30%, 7080% in epidemic period,URI, catarrh (sore throat red and edematous mucosa, mucous discharge),Petechia

28、 ecchymosis,Bacterial emboli,Vascular paralysis, dilation, thrombosis,shock,bilateral severe hemorrhage of adrenal cortex ( Waterhouse- Friderichsen syndrome),(+),Meningitis - Pathological Changes,Vassels: bacterial thrombi, thrombosis, focal hemorrhage Meninge: acute purulent inflammation Gross: du

29、ra: tense, hyperemic Subarachnoid space filled with grayish yellow pus especially at convex of hemisphere，at the base in cisternae, and along circle Willis, roots of cranial & spinal Nerves LM： Strikingly enlarged subarachnoid space with large amount of purulent exudation , mainly polys. Vascular co

30、ngestion Adjacent brain parenchyma be edematous,MeningitisClinical Pathological Correlation(CPC),Meningeal irritation signs,inflammation,Swelling of roots of cranial & spinal N,Compression at ostiole or intervertebral holes,Preventive muscular spasm at back in order to fix the position of nerve root

31、 at holes,Kernigs Sign(+),Brudzinski Sign(+),neck stiffness or opisthotonus,Meningitis CPC,Hypertention of ICP,Inflammatory exude,adhesion of arachnoid granules,decreasing absorption of CSF,vascular congestion,cerebral edema,Projectile vomiting,headache,coma,CSF changes,MeningitisCPC,CSF Changes Inc

32、reasing pressure Turbid, protein ，cell count Pus(+), bacteria(+) Sugar,MeningitisCPC,Waterhouse-Friderichsen syndrome(华佛氏综合征),severe septicemia,large amount of endotoxin released,DIC,shock,bilateral hemorrhage of adrenal cortex,Extensive ecchymosis purpura,Mild or no meningeal changes,Prognosis: qui

33、te good. The usage of antibiotics makes more than 90% patients recovered . Complications: quite few hydrocephalus:脑积水 due to inflammatory adhesion, decreasing absorption of CSF cranial nerve injury: palsy, blindness, deafness strabismus (III、IV、V、VII ) Cerebral infarction脑梗死: inflammation vessels in

34、flammatory injury and occluded focal adhesive arachnoiditis,Meningitis - Consequence and prognosis,Remarks on viral infection,Absolute parasitism in host cells, selective vulnerability of different group of neuron. 绝对细胞内寄生 403 Invades neuron: cytolysis, inclusion body formation 狂犬病Negri小体 Glia cell

35、proliferation, multinuclear giant cell(HIV) T/B cell immunity,Epidemic Japanese B Encephalitis(流行性乙型脑炎),The disease is caused by Japanese B Encephalitis (RNA) virus, most cases show acute clinical course, epidemic in summer and autumn. Victims are children, teenagers, with drowsiness, higher fever,

36、severe headache, convulsion, vomiting, deep coma. Basic pathological change is alteration dominant inflammation 变质性炎症 Permanent immunity after suffering of disease,Encephalitis B Jap.,Pathogen：Encephalitis B Jap. Virus (RNA) Route of Infection,bite of mosquito,virus,Endothelium of local blood vessels,M further multiplication,viremia,normal immunity & B