Pathogeniccocci病原性球菌

1. Pathogenic cocci 2. Other bacteria,1. Pathogenic cocciConcept of pathogenic bacteria 13minStaphylococcus (Esp., S. aureus) 56minStreptococcus (Esp., S. pyogenes) 38minEnterococcus species and VRE 5minNeisseria meningitides Neisseria gonorrhoeae 13min2. Other bacteriaPseudomonas aeruginosa 10min,Highlights of content,Up to every pathogen, the following will be talked:,Biological properties Pathogenicity Immunity Microbiological detections Prevention and treatment,Pustule (膿皰) by S. aureus,Pustule (膿皰) by S. aureus,Paronychia (甲溝炎) by S. aureus,Sore throat (咽喉炎) by S. pyogenes,Untreated erysipelas (丹毒) by S. pyogenes with skin sloughing and necrosis,Necrotizing Fasciitis (壞死性筋膜炎)by flesh-eating bacteria (S. pyogenes, anaerobic bacteria, etc.), and insects (bee, etc.) stinging,Chest x-ray Film 1just a few hours of rigors and productive cough,Chest x-ray Film 212 hours laterconsolidation in the right upper lobe,Lobar pneumonia (大葉性肺炎) by S. pneumoniae,Meningococcal septicemia (腦膜炎球菌性敗血癥) by N. meningitidis, widespread ecchymoses,Gonococcal conjunctivitis (淋菌性結膜炎) by N. gonorrhoeae,Causative agents of above clinical diseases?,What is Pathogenic cocci ? also called Pyogenic cocci (化膿性球菌),Including -Staphylococcus (S. aureus & S. epidermidis) (金黃色葡萄球菌與表皮葡萄球菌 ) -Streptococcus (Group A Streptococci, S. pyogenes) (A群鏈球菌 or 化膿性鏈球菌) -Streptococcus pneumoniae (肺炎鏈球菌) -Neisseria gonorrhoeae (淋病奈瑟菌) -Neisseria meningitidis (腦膜炎奈瑟菌),Important cocci,Staphylococcus aureus,Important pyogenic coccusLeading pathogen of wound infections (including other staphylococci),Shape, Stain & Culture spherical, elliptical, irregular grape-like cluster Gram+ (G+) Grow well on basic medium,Biological properties,Antigenic structure Staphylococcal protein A (SPA) One kind of surface protein in cell wall Single chain peptide Actions Binds (bacterium) to hosts IgG1, IgG2 & IgG4 coagglutination test Competes w/ Fc receptors of phagocytes resists phagocytosis,Coagglutination test with inert particles (e.g., heat-killed S. aureus or latex beads),SPA may resist phagocytosis by competively binding with Fc receptors of phagocytes,Capsule Teichoic acid (polysaccharide) polysaccharide A S. aureus polysaccharide B S. epidermidis,Phases of phagocytosis,Important Properties of 3 Main Species of Staphylococci,Pathogenicity & immunity,Pathogenic substances,Coagulase,Virulence Protection actions Infection localized,Bound coagulase(結合凝固酶) or clumping factor(凝聚因子) plasma to be cloted or bacteria to coagulate Slide coagulase test,classified into -, -, -, & -toxin -toxin makes pores in cell membranes,Staphylolysin(葡萄球菌溶素),kills or degranulates neutrophils & macrophages,including type A & type B causes staphylococcal scalded skin syndrome (SSSS),Exfoliatin (表皮剝奪毒素),Others,heat-stable nuclease (耐熱核酸酶),Clinical diseases,Invasive diseases,Toxin-mediated diseases,Pyogenic infections -local infections-systemic infections,-food poisoning-staphylococcal scalded skin syndrome (SSSS)-toxic shock syndrome (TSS),Folliculitis (毛囊炎) by S. aureus,Bullous Impetigo by S. aureus,A S. aureus infection on a 12-year-old childs cheek,Pathogenesis of staphylococcal infections,Microbiological diagnosis,Identification of pathogenic staphylococci,Coagulase (+) Heat-stable nuclease (+) Golden pigment (+) Hemolyzation (+) Mannite fermentation (+),Prevention & treatment,Methicillin-resistant S. aureus, MRSA (耐甲氧西林金黃色葡萄球菌),Coagulase-negative staphylococci (CNS) (凝固酶陰性葡萄球菌),Compare the features of common pyogenic bacteria.Discuss the pathogenic features and identification points of Staphylococcus aureus.,Questions:,Streptococci,G+, spherical, elliptical, arranged in chain Grow well on nutrient medium w/ blood,Biological properties,Shape, Stain & Culture,Antigenic structure,Protein antigen surface Ag, outside C antigen type-specific including M,T,R,S in Group A Polysaccharid antigen C Ag group-specific Nucleoprotein P Ag non-specific,Classification,Pathogenicity,Group A Streptococci (S. pyogenes),Pathogenic substances,Streptolysin S (SLS, 鏈球菌溶素S) -low MW glycopeptide -oxygen-stable -causes -hemolysis on Blood Agar plate -non-antigenic,Streptolysin O (SLO, 鏈球菌溶素O) -protein w/ SH group -oxygen-labile -destroys many kinds of cells -anti-SLO test (ASO test) helpful for diagnosis,Streptolysin,-coded by lysogenic bacteriophage-proteins including serotype A, B, C-causes scarlet fever (猩紅熱)-one kind of superantigens-also causes TSS,Streptococcal pyrogenic exotoxin (SPE) (鏈球菌致熱外毒素),Streptokinase (SK, 鏈激酶)-also called as streptococcal fibrinolysin (鏈球菌溶纖維蛋白酶),Streptodornase (SD, 鏈道酶)-hydrolyzes DNA,Hyaluronidase (透明質(zhì)酸酶)-also called as spreading factor (擴散因子)-hydrolyzes hyaluronic acid in connective tissue-helpful for spreading of bacteria,Clinical diseases,Pyogenic infections,Toxin-mediated diseases,Allergic diseases (late complications),-scarlet fever (猩紅熱)-Streptococcal toxin-mediated TSS,-rheumatic fever (風濕熱)-acute glomeruloniphritis (急性腎小球腎炎),Erysipelas (丹毒) by S. pyogenes,Cellulitis (蜂窩組織炎) by S. pyogenes,Honey-crust lesion typical of S. pyogenes impetigo,Pathogenesis of S. pyogenes infections,Samples,Pus, Blood, Nasopharynx swab,Isolation w/ blood agar plate,distinguishing from S. pneumoniae,Smear & microscopy,G+ streptococci,distinguishing from staphylococciOther streptococci,-hemolysis,Assist-diagnosis for rheumatic fever,-hemolysis,ASO test,Microbiological diagnosis,S. pneumoniae Group B streptococci Group D streptococci Viridans (-hemolytic) streptococci Streptococcus suis (豬鏈球菌) Enterococcus species (腸球菌) & VRE,Other streptococci,Enterococcus species and VRE,Enterococcus spp.(腸球菌),Previously classified as Group D streptococci In 1984, named as genus Enterococcus Gram+ cocci in pairs or short chains Most are facultative anaerobes Complex nutritional requirements Group D specific teichoic acid antigen,Enterococcus spp. viewed by direct fluorescent antibody (FA) reaction,Enterococcus spp.,Commonly found in the intestines of normal healthy individuals (humans and animals). 2 important human diseases-related spp. E. faecalis (糞腸球菌) and E. faecium (屎腸球菌) Cause Urinary tract infections Bacteremia & septicaemia Subacute endocarditis Wound infections Foodborne diseases Meningitis Nosocomial infections,One of important life-threatening nosocomial pathogens Vancomycin Resistant Enterococci (VRE, 耐萬古霉素腸球菌) Since 1986, VRE infections has become a growing problem,1. Discuss the pathogenic features of Streptococcus pyogenes.2. Discuss identification points between hemolytic streptococci and other pyogenic bacteria.,Questions:,Neisseria gonorrhoeae (淋病奈瑟菌),Biological properties,Shape and stain -G- diplococci in or on PMNs on pus smear -No endospore & flagellum, & w/ capsule & pili,Culture -Obligate aerobes, need 5% CO2 while primary isolation -High nutritional requirement “Chocolate Blood Agar Plate”,Antigenic structure and classification -Pilus protein antigens -Outer membrane protein antigens：PI, PII, & PIII -LOS (lipooligosaccharide, 脂寡糖), LPS-like,N. gonorrhoeae colonies on Chocolate Blood Agar Plate,Pathogenesis,Virulent factors-Pili-Outer membrane proteins-LOS-IgA1 protease-Others,Clinical findings -Gonorrhea -Gonococcal conjunctivitis,Gonorrhea symptoms,Clinical manifestations of N. gonorrhoeae infection,Immunity,Humoral immunity more effective No persistent immune responses Infection trend to -chronic & repeated occurrence,Microbiological detections,Nucleic acids detection, & so on,Samples,Pus secreta from genito-urinary tracts, eyes, & others,Isolation,Oxidase testSugar fermentation testImmunofluorescence assay,Smear & microscopy,G- diplococci in or on PMNs,Colonies & microscopic findings,Biochemical reactions & serologic tests,Other tests,Prevention & treatment,Take preventions as main measure Choose penicillin as No. 1 drug，take care of problems of drugs-resistant bacterial stains,1. What are the main differences between Neisseria meningitides and Neisseria gonorrhoeae.,Question:,Pseudomonas aeruginosa(銅綠假單胞菌),P190,Shape, Stain & Culture G bacili single terminal flagellum appears capsule in