Click to edit Master title style,Click to edit Master text styles,Second Level,Third Level,Fourth Level,Fifth Level,*,*,单击以编辑母版标题样式,单击以编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,第5章,细菌感染的检查方法,Laboratory Diagnosis,1,Outline,Laboratory diagnosis for,bacterial infections,Morphological-microscopic,Molecular,Serological,Laboratory diagnosis for,viral infections,Morphological-electron microscopic,Isolation,Molecular:nucleic acids and proteins,Serological,Laboratory diagnosis for,fungal infections,Morphological-microscopic,Isolation,2,3,Assays,Morphological,assays,Light or electron microscopies,Isolation and differentiation,Serological,assays,Antigen-antibody assays,Molecular,assays,Microorganisms gene(DNA&RNA),4,Principles for Specimen Collection,Sterile manipulation,avoid contamination,Obtain a specimen,from the infected site,according to the disease phase,before administrating antibiotics,Double sera for antibody detections,acute and recovery phase each,Positive if the titer of the later specimen is above 4X to the first specimen,Transport,and store correctly,as soon as possible,Store at-4,o,C for most bacterial specimens,but,keep warm for,Neisseria meningitidis,and,Neisseria gonorrhoeae,Store at-4,o,C -70,o,C for viral specimens,5,Laboratory Diagnosis for Bacterial Infections,Morphological,Protein and Nucleic acids,Antibody,6,Bacteriological Diagnosis,Identifying the organism,Morphological,Isolation&culture,Biochemical reaction,Serological assays,Pathogenesis&antibiotics susceptibility,Animal experiment,Virulence test,antibiotics susceptibility,7,Diagnosis Strategy for Bacterial Infection,8,Morphological,Non-stained,microscopic observation,Dark-field microscopy,Observing the movement of live bacteria,Stained,microscopic observations,Gram stain,Acid-fast stain,Fluorescence stain,9,10,11,12,13,14,15,Isolation&Culture:Colony,Size,Shape,Color,Surface features,Smooth-Rough,Transparency,Hemolysis,16,Biochemical Reactions,Sugar Fermentation H,2,S Test Citrate utilization,17,Serological Assays,Detection,antibody,in the patients serum,A,current infection,should be,IgM positive,A 4-fold or greater rise on antibody titer between the acute serum sample and the convalescent serum sample,Major,drawbacks,A single IgG antibody titer is difficult to interpret because it is unclear whether it represents a current or a previous infection,the convalescent sample is usually taken 10-14 days after the acute sample.By this time,the patient has often recovered and the diagnosis becomes a retrospective one,Some,exceptions,In certain diseases,a single titer of sufficient magnitude can be used as presumptive evidence of a current infection,18,Animal experiment,Animals,MouseGuinea Pig Rabbit Dog Monkey,Inoculation routes,Intradermal Subcutaneous,Intraperitoneal Intravenous,Intracranial/intracerebral Intraspinal,Intranasal Lavage,19,Virulence Test,Median lethal dose,LD50,Median infective dose,ID50,Elek Plate,Diphtherotoxin,Corynebacterium diphtheriae,Enterotoxin,enterotoxigenic,E.coli,20,Antibiotic Susceptibility Test,Method,21,MIC&MBC,Minimum Inhibitory Concentration，MIC,Minimum Bactericidal Concentration，MBC,Bactericidal drugs,usually have an MBC equal or very similar to the MIC,Bacteriostatic drugs,usually have an MBC significantly higher than the MIC,22,23,Bacterial Proteins,DNA&RNA,Antigens(Proteins),Known antibodies,Agglutination,coagulation,precipitation,ELISA,Immunofluorescence,radioimmunoassay,DNA&RNA,PCR,Nucleic acid hybridization,24,Detection of Bacterial Antigens,Precipitation test,Coagglutination test,Immunoflorecence,IF,McAb technique,25,26,27,28,Bacterial DNA&RNA,PCR,DNA probe&hybridization,DNA hybridization(southern blot),Plasmid fingerprint analysis,Restrict multimorphologic analysis,29,30,31,PCR,32,33,Gene Chip/microarray,34,Diagnosis Strategy for Bacterial Infection,35,Section B,Prevention and treatment,36,Prevention,Prevention,Passive,immunity,Active,immunity,Vaccines,Adjuvants,Human,Immune-globulin,Animal sera,and antitoxins,37,The difference of artificial active and passive immunity,Active immunity,Items,Passive,immunity,Immuno substance,Time for response,Duration,Main usage,Antigen,Antibody or cytokine,Slow,24 weeks,Fast,just when the substance injected,Long,several months several years,Short,23 weeks,Prevention,Prevention and emergency treatment,38,Vaccines,Vaccines,Live(attenuated)vaccines,Inactivated vaccines,Subunit vaccines,Plant vaccines,Therapeutic vaccines,DNA vaccines,39,Artificial passive immunity,Antitoxin(抗毒素),antisera（抗血清）,Immunoglobulin（免疫球蛋白）,Cytokine(细胞因子）,40,Antimicrobial chemotherapy,Chemotherapy as a science began with Paul Ehrlich in the first decade of the 20th century.Ehrlich formulated the principles of selective toxicity and recognized the specific chemical relationships between microbial pathogens and drugs,the development of drug resistance,and the role of combined therapy.Ehrlichs experiments led to the arsphenamines(胂凡纳明)for syphilis,the first planned chemother