病理學：傳染病

1、 Bacillary Dysentery 細菌性痢疾細菌性痢疾 shigella dysenteriae（痢疾桿菌）：（痢疾桿菌）：G (-) B group 乙群福氏菌乙群福氏菌(Flexner) D group 丁群宋內氏菌丁群宋內氏菌(Sonne) C group 丙群鮑氏菌丙群鮑氏菌(Boyd) A group 甲群志賀氏菌甲群志賀氏菌(Shiga) Pathogen Pathogen Enteroinvasive organism： proliferate, invade and destroy mucosal epithelial cells， producing enteroto

2、xin（cytotoxin），），cause direct epithelial cell necrosis，acute mucosal inflammation and erosion Infectious enterocolitis patients and bacteria-carriers, feces-contaminated food and drink. Transmission sources Pathological changes Location: Mainly affect the distal colon (rectum and sigmoid colon) - te

3、nesmus（里急后重）（里急后重），severe cases involving whole colon or even distal ileum Microscopy: acute fibrinous and purulent inflammation affecting mucous and submucous layer Gross： Early: acute serous inflammation: hyperemia, edema, spotty hemorrhage Progression: pseudomembranous inflammation, destruction o

4、f the mucosa leads to erosion Clinical Manifestation Mucopurulent bloody stool（粘液膿血便）（粘液膿血便） Tenesmus（里急后重）（里急后重） Toxaemia （毒血癥）（毒血癥） Dont cause enterostenosis Clinical categories acute bacillary dysentery chronic bacillary dysentery toxic bacillary dysentery Typhoid Fever 傷寒，腸傷寒傷寒，腸傷寒 Pathogen Salm

5、onella typhi.： G(-)，rod-shape, with flagellum Grow well in bile，bacteria may be contained in the bile even after clinical healing or the whole life bacteria carrier Enteropathogenic bacteria, invade and damage the intestine Pathogen Produce endotoxin： Fever Degenerative and necrosis of myocardium, s

6、keletal muscle. Stimulate the vagus（迷走神經(jīng)），（迷走神經(jīng)），resulting the sluggish pulse （相對緩脈）。（相對緩脈）。 Pathogenesis S. typhi. Lymphoid tissue of small intestine 局部繁殖局部繁殖 Stool contaminate food or drink bacteremia 菌血癥菌血癥 Gall bladder colonization Liver, spleen lymph node Septicemia 敗血癥敗血癥 Macrophage proliferat

7、ion Swelling (1 wk) 過敏反應過敏反應 Necrosis, ulcer (2 wks) Healing (1 wk) 排入腸腔排入腸腔 Latent phase （10 days） mouth Transmission source：patients and bacteria-carrier Typhoid fever Basic Pathological changes： Acute proliferative inflammation Proliferation of the mononuclear-phagocytic system （全身單核巨噬細胞系統(tǒng)急性增生性炎）

8、：（全身單核巨噬細胞系統(tǒng)急性增生性炎）： intestinal lymph tissue, mesenteric lymph node, liver, spleen, bone marrow 特征性病變：特征性病變： Typhoid cell （傷寒細胞）：（傷寒細胞）：Macrophages phagocytize bacteria, RBC, lymphocyte, cell fragments Typhoid granuloma（傷寒肉芽腫（傷寒肉芽腫 ，傷寒小結），傷寒小結）: Localized aggregates of typhoid cells，lymphocyte，plasm

9、a cells. Pathological changes of small intestine Sites: distal ileum Peyer patch（集合淋巴結）（集合淋巴結）and Solitary lymph nodule（孤立淋巴小結）（孤立淋巴小結） 1st wk：swelling stage（髓樣腫脹期）（髓樣腫脹期） Enlargement of focal lymphoid tissue，typhoid granuloma 2nd wk：necrosis stage（壞死期）（壞死期） Ischemic and allergic 3rd wk：ulceration s

10、tage（潰瘍期）（潰瘍期） Ulcer parallel to the intestinal long axis. perforation , hemorrhage 4th wk ：healing stage（愈合期）（愈合期） Granulation tissue, regeneration，formation of scar. ulceration stageswelling stage liver, spleen, mesenteric lymph node，bone marrow Enlargement 1st wk：granuloma 2nd wk：necrosis Patholo

11、gical changes of other monocyte-phagocytic system and organs Clinical Manifestation Bacteremia: Protracted fever(稽留熱）稽留熱） sluggish pulse Muscle：degeneration and coagulative necrosis Skin：papule (rose-rash) Enlargement of lymph nodes, liver, splenomegaly Leukocyte counts (monocyte-phagecyte hyperplas

12、ia of bone marrow） Sexually Transmitted Disease, STD 性傳播疾病性傳播疾病 Acquired Immunodeficiency Syndrome （AIDS） 獲得性免疫缺陷綜合征獲得性免疫缺陷綜合征 艾滋病艾滋病 Worldwide to1996.12.1 2940,0000 HIV infections 840,0000 HIV patients to 2002.11 7000,0000 HIV infections 2800,0000 deaths China to 2002 100,0000 HIV infections Epidem

13、iology Human Immunodeficiency Virus HIV，人類免疫缺陷病毒人類免疫缺陷病毒 Retrovirus belonging to the lentivirus family Human immunodeficiency virus (HIV) HIV-1: USA，Europe，Central Africa，China HIV-2：West Africa Feline（貓）（貓） immunodeficiency virus Simian（猴）（猴） immunodeficiency virus 80-130nm Lipid envelop（derived fr

14、om the host cell membrane） Electron-dense，cone-shaped core Entry of HIV into target host cells Selective tropism for CD4+ cells： CD4: the high-affinity receptor for HIV CD4+ T cells, monocyte，macrophages, dendritic cells Recognition and binding: CD4 - gp120 Coreceptors（輔助受體）（輔助受體）: CXCR4（T cell） - g

15、p120 CCR5（macrophages）- gp120 Penetration and fusion: Gp41 Adapted from Robbins Basic Pathology, 7th edition. RNA reverse transcription to proviral（前病毒）（前病毒） cDNA cDNA integration Transcription and virus budding Infected cells death Transmission routes The exchange of blood or body fluids (semen) th

16、at contain HIV virus or HIV-infected cells Sexual contact 75% of all cases of transmission Heterosexual or bisexual Parenteral inoculation Intravenous drug abuser Transfusion of blood or blood products Mother-to-infant transmission Transplacental During delivery Breast milk Pathogenesis CD4+ T cell，

17、 monophage， macrophage Profound immunosuppression Opportunistic infections Secondary neoplasms Neurologic manifestations （macrophage/microglia） HIV T cell： CD4+ T-Cell ； CD4+ / CD8+0.5； T / B Monocyte/macrophage： Microbicidal activity chemotaxis Antigen presentation Cytokine production B cell functi

18、on abnormality Lymph node： - Early stage：follicular hyperplasia - Progression：follicular involution - Late stage：generalized lymphocyte depletion，lymph node atrophy（“burnt-out”） Other immune organ： spleen and thymus also looks like “wasteland”。 Pathological Changes- Immune System injury Early stage：

19、follicular hyperplasia Progression stage：parafollicular (T zone) depletion Late stage：lymph node atrophy Accounts for 80% of deaths in AIDS patients Disseminated multi-organ and multi-system infection Various pathogens： Fungus： Pneumocystis carinii （卡氏肺孢子菌，（卡氏肺孢子菌，Most common ） Cryptococcosis （隱球菌（隱

20、球菌, CNS） Histoplasmosis（組織胞漿菌）（組織胞漿菌） Candidiasis（念珠菌）（念珠菌） Protozo： Toxoplasma（弓漿蟲）（弓漿蟲） Bacteria：mycobacteria（分支桿菌）（分支桿菌） virus：CMV、JC、HHV- 8 等等 Pathological Changes- Opportunistic infections Kaposi sarcoma Most common Multicentric and more aggressive in AIDS patient human herpes virus 8(HHV8) or

21、KS herpesvirus (KSHV) genomic sequence are found in all KS, including those occur in HIV(-) patient. Non-Hodgkin lymphoma Primaryly high-grade diffuse B cell lymphoma Involve many extranodal sites, especially brain EBV associated Cervical carcinoma HPV infection Pathological Changes- neoplasm Kaposi

22、 sarcoma 90% AIDS patients demonstrate neurologic involvement at autopsy Opportunistic infections Lymphoma AIDS-dementia complex (HIV encephalopathy) Vaculoar myeopathy (空泡性脊髓病空泡性脊髓病) Pathological Changes-central nervous system Condylomata acuminata 尖銳濕疣尖銳濕疣 Pathogen： Human papillomavirus (HPV) Low-

23、risk HPV infection (HPV6 and HPV11) Occur anywhere on the anogenital surface sometimes singly but more often in multiple Female: Vulva, cervix, around the anus Male: penis, around the anus Pathological changes Gross: Pathological changes Exuberant proliferation of squamous epithelium supported by fi

24、brovascular papillae. Characteristic Koilocytosis(挖空細胞挖空細胞): - Perinuclear halo：caused by the lysis of perinuclear cytoskeleton by the viral E4 protein - Irregular hyperchromatic Syphilis 梅毒梅毒 Pathogen Spirochetes Treponema pallidum. Human is the only natural host. Adapted from Robbins Basic Patholo

25、gy Source of infection active cutaneous or mucosal lesion in a patient in the primary or secondary phages of syphilis. Transmission routes: minute breaks in the skin or mucous placental Common in HIV-infected patients Primary syphilis 一期梅毒一期梅毒 infection 2-6 wk Disseminated to distant sites by lympha

26、tics and bloodstream Secondary syphilis 二期梅毒二期梅毒 Highly infectious 1 yr10-20 yr Late latent phase Early latent phase Tertiary syphilis 三期梅毒三期梅毒 Less infectious 2 m Hard chancre（硬下疳）（硬下疳） at the site of pathogen entry penis; vagina or cervix Gross: begins as a small, firm papule, gradually enlarges t

27、o produce a painless ulcer with well-defined, indurated margins and a clean moist base. resolve 4-6 wks Pathological changes of primary syphilis Adapted from Robbins Basic Pathology Microscopy: Proliferative endarteritis （endothelial hypertrophy and proliferation） intimal fibrosis and narrowing of t

28、he vessel lumenlocal ischemia，necrosis，fibrosis Inflammatory infiltrate rich in plasma cells Spirochetes readily demonstrable， serologic test often negative Pathological changes of secondary syphilis Generalized lymphadenopathy: nonspecific follicular hyperplasia Mucocutaneous lesions ：maculopapular

29、, scaly or pustular Microscopy: Proliferative endarteritis Inflammatory infiltrate rich in plasma cells Spirochetes readily demonstrable，serologic test positive Resolve several wks Cardiovascular syphilis: syphilitic aortitis梅毒性主動脈炎梅毒性主動脈炎 80% endarteritis of the vasa vasorum（滋養(yǎng)（滋養(yǎng) 血管）血管） of the pro

30、ximal aorta scaring of the aortic media progressive dilation of the aortic root and archaortic insufficiency and aneurysms of the proximal aorta narrowing of coronary artery ostia in some cases (myocardial ischemia) Pathological changes of tertiary syphilis Pathological changes of tertiary syphilis Neurosyphilis（神經(jīng)梅毒）（神經(jīng)梅毒）: 10% Chronic meningovascular disease, tabes dorsalis(脊髓癆脊髓癆) , general paresis Benign tertiary syphilis：Gumma（樹膠腫）（樹膠腫） irregular， firm mass of necrotic tissue surround by connective tissue. Related with delayed