临床病原学检查022.ppt

1、1,临床病原学检查,上海第二医科大学 附属瑞金临床医学院检验系 洪秀华 卫蓓文,2,病例分析 以性传播性疾病为例,【病史摘要】 （一）入院病历 患者：陈某，男性，25岁，音响推销员，未婚。1998年3月8日入院。住院号32334。 主诉：龟头部长“疱疮”，反复不愈。,3,现病史：阴茎、包皮两侧、龟头部出现小水疱，疼痛难忍。患者2年前曾与一酒店服务员热恋，有过性接触。此后约10天左右，龟头部感到灼热，不久即感疼痛，并出现几个小水疱。很快破溃渗水。经某医院诊治，按“性病”治疗，注射“利福平”、“淋必治”等药物，未见好转，反而创面扩大，水疱溃破相连成片，20余天后相继消退。约12月后，外生殖器又出现

2、小水疱，症状比前更为严重，故来院就诊。 既往史：身体健康，无其他系统疾患。 个人家庭史：无不良生活史，父母健在。,4,体格检查：神志清，全身倦怠。体温37.6，脉搏72次/分，呼吸21次/分，血压110/70mmHg。心肺检查无异常发现，腹 ，肝脾未及，无肾区叩击痛。外生殖器皮肤见阴茎、龟头部有豌豆、米粒、大头针大小不一的小水疱，部分水疱融合，破溃，中央伴糜烂，微痛。腹股沟淋巴结稍肿大，压痛明显，排尿不适，下肢疼痛。 辅助检查：旧结核菌素试验弱阳性，肾B超检查未见异常，尿液一般检查WBC（+）、RBC（），蛋白（-）疱疹分泌液涂片、革兰染色、镜检，未见革兰阴性双球菌。,5,入院初步诊断：性传播

3、性疾病，（Sexually transmitted diseases,STDs）可疑生殖器疱疹（再发型）。,6,临床病原体检查目的:,临床病原体检查目的: 是确定感染的发生和性质，在疾病早期提供恰当的治疗方案，并采取有效的预防措施，防止感染传播造成的危害。,7,各种不同病原体的实验诊断方法遵循以下基本原则：,1.正确、规范采集和运送标本。 2.直接显微镜查见病原体或检出病原体抗原，借助分子生物学的方法检测病原体核酸，结合病人的病史、症状或体征，快速作出初步诊断。,8,各种不同病原体的实验诊断方法遵循以下基本原则：,3.初步诊断同时，对病原体进行分离与鉴定。 4.检测机体对病原体的免疫产物。 5

4、.参与临床选择抗菌药物，指导 和监控微生物的治疗方案，避免 耐药菌株的产生。,9,姬姆萨染色衣原体包涵体,HSV病毒,被支原体感染的精子,梅毒螺旋体,10,检测项目显微镜检查,阴道、尿道分泌物 下疳、湿疣、脓疱疹液 疱疹基底组织刮片 宫颈拭子或刮片,11,检测项目分离、培养、鉴定,标本接种： 选择合适的培养基、观察菌落性状作生化鉴定 病毒、立克次体、衣原体、接种细胞或易感动物观察增殖指标和血清学方法鉴定。,12,检测项目分离、培养、鉴定,A、在培养基上1/4的表面滚动棉拭接种 B、装淋球菌培养皿的合适罐子,13,检测项目分离、培养、鉴定,C、巧克力琼脂上淋病奈瑟菌菌落 D、几种奈瑟菌的快碳水化

5、合物降解试验,14,检测项目抗体检测 梅毒血清学试验,非密螺旋体抗原试验： （venereal disease reearch laboratory，VDRL） 不加热血清反应素玻片试验（USR） 快速血浆反应素环状卡片试验（RPR） 自动反应素试验（ART）,15,检测项目抗原检测,1、单纯疱疹病毒抗原检测 2、HIV抗原检测 3、衣原体抗原检测,HIV抗原检测实验原理示意图,16,检测项目核酸检测,1、HIV核酸检测 2、梅毒螺旋体PCR检测 3、衣原体核酸探针 4、支原体核酸检测,17,细菌感染检查检验特点,通过对标本直接显微镜检，病原菌的分离培养鉴定，病原菌的抗原检测，核酸检测和细菌感

6、染后机体免疫应答产物的测定及药物的测定及药物敏感性试验，对细菌感染性疾病可作出及时、准确的病原学诊断。,18,检测程序,19,Diagnosis of bacterial infections,The identification and differentiation of bacteria principally relies: -on microbial morphology and growth variables on culturing the organisms on non-selective and selective media. Culture remains the s

7、tandard for diagnosis of bacterial infection because it is the simplest,the most reliable and the most cost efficient method. Another advantage is the fact that parallel testing of the sensitivity towards antibiotics is possible.,20,n molecular-biological technics that provide rapid identification o

8、f infectious agents,both from culture isolates and directly within clinical specimens. - on the detection of the antibody response to the pathogen. The concentration of infection-sepcific antibodies is determined in titers or activity units.,21,In principle,the pathogen should be identified by cultu

9、re in any acute infection that requires treatment.This,however,is only possible if the pathogen is still detectable in excretions,secretions,blood or tissue at the time when the clinical symptoms occur,e.g. salmonellae in feces in the case of diarrhea or gonococci from endocervical canal in genital

10、tract infection.,22,病毒感染检查检验特点,标本处理：必须经滤过除菌，标本需迅速冷藏、运送。 病毒分离培养后，根据细胞病变特征确定病毒的种，对已分离的病毒用已知参考血清作中和试验、补体结合试验、血凝抑制试验。 新的早期诊断技术：核酸杂交技术、PCR技术。,23,病实 毒验 感室 染诊 性断 疾 病 的,24,Diagnosis of viral infections,The primary diagnostic technique for most viral infections is the isolation of the virus in cell culture.

11、Serologic techniques may also be useful, especially if the virus was isolated from a nonsterile site. In some instances, serologic diagnoses is the only practical approach in a clinical laboratory. Direct detection of antigen in body fluids or tissues has also been effective for some viruses. The li

12、st of agents for which direct detection of antigen is useful will undoubtedly continue to expand.,25,The compare of the advantages and disadvantages of each of these approaches: Culture: Time:Days to weeks Advantages:Specificity and sensitivity maximum;isolate available for characterization Disadvan

13、tages:Cell culture facilities needed;time for diagnosis may be long,26,Direct detection: Time:Hours to 1 day Advantages:Speed of diagnosis;used for viruses difficult to culture Disadvantages:False-positives and negatives;hard to batch tests Serology: Time:Weeks Advantages:Assessment of immunity or r

14、esponse to virus isolated from nonsterile site; used for viruses difficult to culture Disadvantages:Potential cross-reaction;need for acute and convalescent specimens,27,真菌感染检查检验特点,形态学检查为检测真菌的重要手段 抗原检测适合血清和脑脊液中隐球菌、念珠菌、夹膜组织胞浆菌。 血清学诊断适用于深部真菌感染。,28,Direct Examination,It is highly recommended that a direct microscopic examination be made on most this provide an immediate presumptive diagnosis for the physician, but it may also aid in the selection of an appropriate culture medium. A phase-contrast microscope i