gram negative rods挑剔的革兰阴性杆菌（ppt30）课件

Aerobic Gram-Positive Bacilli Part II Division of Medical Technology Carol Larson MSEd, MT(ASCP) Gram stain Morphology Arrangement Formation of spores Catalase reaction Differentiation of Major GPR Genera Spore-forming GPR, catalase positive Bacillus species Bacillus anthracis Bacillus cereus Nonspore-forming GPR, catalase positive Listeria monocytogenes Corynebacterium species (diphtheroids) Corynebacterium diphtheriae Corynebacterium jekeium GPR Discussed in Student Lab Nonspore-forming GPR, catalase negative Gardnerella species Erysipelothrix species Lactobacillus species Branching Nocardioform GPR Nocardia species Streptomyces species GPR Discussed in This Lecture Two types Short GPR Long, filamentous GPR Non-sporulating Erysipelothrix rhusiopathiae Gram Stain GPR, pleomorphic, Non-spore forming, Catalase negative Erysipelothrix rhusiopathiae Colony Morphology Grows on BAP Nonhemolytic or alpha hemolytic Microaerophilic GPR, pleomorphic, Non-spore forming, Catalase negative Catalase negative Motility Nonmotile Test-tube brush growth pattern in semisolid motility tube at 48 hours H2S positive in KIA/TSI (only GPR) Sucrose non“F” Erysipelothrix rhusiopathiae Identification GPR, pleomorphic, Non-spore forming, Catalase negative Zoonotic Swine erysipelas (fatal to pigs) Man skin disease Erysipelas Direct contact with infected animal Rarely disseminates causing septicemia with arthritis or endocarditis Erysipelothrix rhusiopathiae Clinical Significance GPR, pleomorphic, Non-spore forming, Catalase negative What are the key biochemical reactions that identify Erysipelothrix rhusiopathiae? Two gram stain morphologies (GPR), two colony types on SBA, catalase negative, H2S positive, test- tube brush pattern in motility tube, sucrose non“F” Two types Long slender GPR in chains Short GPCB Non-sporulating Lactobacillus species Gram Stain GPR, pleomorphic, Non-spore forming, Catalase negative Grows on BAP Multiple colony morphologies Nonhemolytic or alpha hemolytic Microaerophilic Lactobacillus species Colony Morphology GPR, pleomorphic, Non-spore forming, Catalase negative Catalase negative Sucrose “F” Vancomycin “R” Lactobacillus species Identification GPR, pleomorphic, Non-spore forming, Catalase negative Lactobacillus species Clinical Significance Normal flora Mouth GI tract Female vaginal tract Rarely pathogenic Endocarditis Meningitis GPR, pleomorphic, Non-spore forming, Catalase negative What is the clinical significance of Lactobacillus species? It is considered normal flora of the mouth, gastrointestinal tract, and female genital tract Nonspore-forming GPR, catalase negative Gardnerella species Erysipelothrix species Lactobacillus species Review Actinomycetes Nocardia species Streptomyces species Branching Nocardioform GPR Nocardia species Gram Stain Pleomorphic, branching, fine, delicate filaments with fragmentation GPR Often appears beaded Branching Nocardioform GPR Grows on SBA, Mycology media and LJ media Aerobic growth appears at 3-30 days Waxy, bumpy or velvety rugose forms, yellow to orange colonies Nocardia species Colony Morphology Branching Nocardioform GPR Nocardia species Identification Partially acid-fast positive Presence of granules in specimen Catalase positive Branching Nocardioform GPR Nocardia species Clinical Significance Habitat: soil and water Mycetoma (actinomycetoma) Tissue swelling Draining sinus tracts Presence of granules Immunocompromised patients Pulmonary and disseminated infections Branching Nocardioform GPR What is the key characteristic in identifying Nocardia species? Branching GPR that is partially acid fast positive What primary disease does Nocardia cause and what 3 symptoms are seen? Mycetoma (aka actinomycetoma). Triad of symptoms: tissue swelling, draining sinus tracts, and the presence of granules GPR with extensive branching, chains and spores Does not fragment easily Streptomyces species Gram Stain Branching Nocardioform GPR Streptomyces species Colony Morphology Grows on SBA, Mycology media and LJ media Aerobic growth appears at 3-30 days Waxy, bumpy or velvety rugose forms, yellow to orange colonies Branching Nocardioform GPR Acid-fast negative Streptomyces species Identification Branching Nocardioform GPR Streptomyces species Clinical Significance Habitat: soil and decaying vegetation Mycetoma (actinomycetoma) Rarely: Pericarditis Bacteremia Brain abscess Click icon for audio Branching Nocardioform GPR How can you differentiate Streptomyces from Nocardia? Streptomyces is acid-fast negative and Nocardia is partially acid-fast positive Nonspore-forming GPR, catalase negative Gardnerella species Erysipelothrix species Lactobacillus species Branching Nocardioform GPR Nocardia species Streptomyce