呼吸道感染细菌中山大学微生物学.ppt

1、呼吸道感染的细菌,结核分枝杆菌 白喉杆菌 军团菌 乙型链球菌 肺炎链球菌 脑膜炎球菌 百日咳鲍特菌 流感嗜血杆菌,分枝杆菌属Mycobacterium,分枝生长 细胞壁含大量脂质分枝菌酸 抵抗盐酸酒精脱色（抗酸染色阳性） 致病菌生长缓慢 引起慢性疾病，伴肉芽肿,分类 人型结核分枝杆菌 牛型结核分枝杆菌 结核分枝杆菌复合群 非洲分枝杆菌 田鼠分枝杆菌 麻风分枝杆菌 非结核分枝杆菌,Mycobacteria tuberculosis, Discovered tuberculosis bacillus and method of growing it in pure culture in 1882.

2、 Awarded by Nobel Prize for medicine in 1905,Dr. Robert Koch (1843-1910),Tuberculosis结核病(TB),It is primarily a slowly progressing infectious disease of the lungs caused by the bacterium Mycobacterium tuberculosis . Mycobacterium bovis is also a causative agent.,Bacillus Calmette-Gurin (BCG ),a vacci

3、ne against tuberculosis that is prepared from a strain of the attenuated (weakened) live bovine tuberculosis bacillus,Camille Gurin,Albert Calmette,1943,Selman A. Waksman purified streptomycin ,showed inhibition of M. tuberculosis in animal test. In 1952 he was awarded the Nobel Prize streptomycin t

4、he first antibiotic active against tuberculosis,Selman A. Waksman,结核分枝杆菌的流行现状,80年代以前结核病死亡率,80年代以后结核病死亡率,中国： 2006年新发结核病例460万 死亡13万 每年3月24日 世界结核日(World TB day),(Mycobacterium tuberculosis),1. 生物学性状 细胞壁中含大量分枝菌酸 抗酸染色阳性 染色后不易被盐酸酒精脱色,致病菌: 人型及牛型结核杆菌,结核分枝杆菌,结核杆菌（抗酸染色）, 需氧菌，3042生长, 缓慢 可诱导致L型 非抗酸性G+颗粒Much颗粒,结

5、核杆菌L型, 常用Lowenstein-Jensen培养基或土路豆Trudeau培养基 蛋黄 脂质生长因子 孔雀绿 抑制杂菌生长 菌落特点: 干燥、颗粒状、结节样、菜花样米黄色菌落 液体培养基中形成菌膜,不发酵糖类 热触酶试验 可鉴别结核杆菌和非结核杆菌, 抵抗力 耐干燥:干燥痰中6-8个月 烈日曝晒2小时 耐酸、碱:Acid: 3%HCl or 6% H2SO4 Alkalis:4%NaOH 蛋白质 保护 对湿热、紫外线 、乙醇敏感 链霉素、异烟肼、利福平 敏感 但易产生耐药,变异多见 形态变异 毒力变异 BCG(卡介苗) 耐药性变异 对异烟肼（INH）耐药 编码过氧化氢-过氧化物酶的基因（

6、katG)中心部位突变或katG基因缺失以及inhA（enoyl-ACP还原酶基因）的调节基因发生突变。,对利福平耐药 编码细菌RNA聚合酶亚单位的rpoB基因突变，使该酶不再与利福平结合而耐药。 在rpoB基因中央附近69bp的高变区域内，存在35种以上的错义突变，其中以Ser531Leu和His526 Tyr最常见，约占总突变65%以上。 对链霉素耐药 编码细菌16SrRNA的rrs基因和编码S12蛋白的rpsL基因发生突变，使16SrRNA与链霉素无法结合。,致病物质,脂质: 索状因子(6,6-双分枝菌酸海藻糖)：破坏线粒体膜，抑制白细胞游走，引起慢性肉芽肿 磷脂：促使单核细胞增生，抑制

7、蛋白酶的分解作用,使巨噬细胞转变为类上皮细胞，形成结核结节和干酪样坏死 蜡质D：分枝菌酸和糖肽脂复合物，具佐剂作用,引起迟发性超敏反应 硫酸脑苷脂：抑制吞噬细胞的吞噬体与溶酶体结合 蛋白质: 结核菌素(无毒) 蜡质D 超敏反应,Fluorescent stained microcolonies of M.tuberculosis showing serpentine cord formation,原发感染,结核杆菌 吸入 肺泡, 巨噬细胞吞噬 脂质抗吞噬 繁殖后破坏巨噬细胞 释放 炎症原发灶 肺门淋巴结肿大 原发综合征 磷脂 朗罕巨细胞 干酪样坏死 结核杆菌潜伏 结核结节 其他系统结核 愈合,

8、绝大部分,约15%,The granuloma of primary tuberculosis,Tuberculous nodules in the lung of a patient with tuberculosis.shows the caseous necrosis.,Primary pulmonary tuberculosis,X-RAY shows the lung of the patient suffering miliary tuberculosis,原发后感染 内源性 原发病灶内 外源性 重新感染 病灶多局限 干酪样坏死灶 钙化，痊愈 形成空洞,The clinical s

9、igns of pulmonary tuberculosis Low-grade fever weight loss, cough, night sweats, malaise chest pain Blood stained sputum血痰 (phlegm粘痰) hemoptysis(咯血).,肺外结核,细胞免疫为主 单核巨噬细胞在IL-2、 IL- 6及IFN- 等作用下, 吞噬功能 细胞免疫和超敏反应并存 （郭霍现象）,3. 免疫性,结核菌素试验 旧结核菌素(OT) 纯蛋白衍生物(PPD)：PPD-C和BCG-PPD 目的： 检测机体是否感染过结核杆菌,机体对结核杆菌是否有超敏反应及检

10、测机体的细胞免疫功能. 方法： PPD-C和BCG-PPD各5单位分别注射两 前臂皮内 结果：阳性(5mm) 已感染过结核杆菌或 接种过卡介苗 强阳性（ 15mm) 活动性结核病 阴性 一般表示未感染过结核杆菌,意义： 确定BCG接种对象和测定接种效果 临床诊断意义，强阳性(15mm) 测定机体的细胞免疫功能 未接种人群TB感染的流行病学调查,4. 微生物学检查,标本 ：痰、支气管灌洗液、尿、脑脊液等 涂片镜检 抗酸染色初步诊断 金胺染色提高检出率 集菌 离心、4%NaOH 、3%HCl 分离培养 Lowenstein-Jensen培养基或土路豆培养基,颗粒、结节、菜花样菌落 快速诊断 PCR

11、, 有假阳性,More sensitive than an acid fast stain, this auramine stain requires fluorescence microscopy. Note the yellow-orange rod-like mycobacteria. Of course, the most sensitive method for detection of mycobacteria is microbiologic culture,5. 防治, 新生儿接种卡介苗：注意复查 世界范围内有效率0-80% 监测流行情况 发现和治疗痰菌阳性者：我国免费治疗 治

12、疗原则: 利福平、异烟肼联合用药,防止产 生耐药,Treatment,prevention,and control,Regimens recommended for treatment include isoniazid(INH)异烟肼and rifampin for 9 months ,with pyrazinamide吡嗪酰胺and ethambutol乙胺丁醇or streptomycin added for drug-resistant strains. 全程、足量,DOTS is a abbreviation of Directly Observed,二. 麻风杆菌Mycobacte

13、rium leprae, Cause Leprosy(麻风病) positive acid-fast stain . cant culture with artificial medium. Can multiply and passage within the paws of mouse and armadillo犰狳,armadillo犰狳,Acording the clinical manifestation ,leprosy has been divided into: tuberculoid(TT) leprosy结核样型麻风 lepromatous(LL) leprosy瘤型麻风

14、Intermediate forms,Borderline tuberculoid(BT) mid-borderline (BB) borderline lepromatous(BL ),中间型麻风,tuberculoid(TT) leprosy结核样型麻风, Is associated with cellular immnity directed hyper-reactive damage of skin and peripheral nerves trunks. The resulting nerve damage is responsible for the main clinical

15、features of leprosy: anaesthesia(感觉消失) and muscle paralysis. Repeated injuries to,and infections of ,the anaesthetic extremities leads to their gradual destruction,result in deformation eventually.,tuberculoid(TT) leprosy结核样型麻风,lepromatous(LL) leprosy瘤型麻风, mainly infected skin and mucous membrane. W

16、ith dysfunction of cellular immunity,the pathological damage is related to Ag-Ab complex the skin lesions are numerous or confluent and contain huge numbers of bacilli,usually seen as clusters or globi within monocytes. Cooler parts of the body ,such as the ear lobes,are particularly heavily infiltr

17、ated by bacilli.,Biopsy stained with acid-fast stain,shows that in the clinical material from lepromatous patients,the bacilli are typically found within macrophages in dense clumps(called leprotic globi).,麻风球,Destruction of the nasal bones may lead to collapse of the nose,白喉棒状杆菌Corynebacterium diph

18、theriae, G+ rods with tapered end Neisser染色不均匀，有异染颗粒 Cells often contain metachromatic granules异染颗粒(成分:polymetaphosphate) 作用: 储存养料 有鉴定价值,C. diphtheriae Cells often contain metachromatic granules(polymetaphosphate) which stain bluish purple with methylene blue,Culture medium, Loeffler medium Pais med

19、ium（白氏培养基) diagnostic and selective medium： On blood agar medium containing tellurite亚碲酸钾血平板 ,colonies of C. diphtheriae are characteristically black or grey after 24-48h.,白施恩教授,On blood agar medium containing tellurite ,colonies of C. diphtheriae are characteristically black or grey,Pathogenesis, I

20、s the causative agent of diphtheria, diphtheria is an acute upper respiratory tract disease.,respiratory droplets Contact or inhalation Bacteria muitiply intonsils,and Throat,covered with pseudomembrane diphtheria toxin (DT) Blood,heart Peripheral nerves adrenal glands,myocarditis,neuritis,Pathogene

21、sis,diphtheria toxin (DT) is the main virulent factor.,B,A,Binding receptor,ADPR transmissionase activity,Inhibit the protein synthesis of host cells, The gene of DT is located in the genome of -phage ,so Corynebacterium diphtheriae only produces diphtheria toxin when lysogenized by - phage.,白喉毒素的作用机制：抑制蛋白质合成,所致疾病,白喉 急性呼吸道传染病 传染源: 病人 传播途径: 呼吸道、飞沫 致病过程 鼻粘膜繁殖产毒 炎性细胞 假膜 坏死组织 白喉杆菌 脱落 堵塞呼吸道 窒息,3. 免疫性,抗毒素为主,4. 微生物学检