HomeCoursesMEDSCI 202: Microbiology and ImmunologyLecture 5 Lecture 5 0% Question 1 of 64 What does staphylococci mean?= (2) Staphylo - bunch of grapes, cocci - granules What does staphylococci mean?= (2) Staphylo - bunch of grapes, cocci - granules Question 1 of 64Question 2 of 64 What are the 3 important species? =(3) S. aureus, S. epidermidis, S. saprophyticus What are the 3 important species? =(3) S. aureus, S. epidermidis, S. saprophyticus Question 2 of 64Question 3 of 64 Where is S. aureus found?= (3) Oropharynx, GI tract, urogenital tract Where is S. aureus found?= (3) Oropharynx, GI tract, urogenital tract Question 3 of 64Question 4 of 64 What are characteristics of S. aureus? =(6) Irregular cell clusters, gram +ve, spherical (cocci), non motile (no flagellum), halodurant What are characteristics of S. aureus? =(6) Irregular cell clusters, gram +ve, spherical (cocci), non motile (no flagellum), halodurant Question 4 of 64Question 5 of 64 How many adults are asymptomatic persistent nasopharyngeal carriers of S. aureus?= 15% How many adults are asymptomatic persistent nasopharyngeal carriers of S. aureus?= 15% Question 5 of 64Question 6 of 64 Which occupation has a high number of carriers= of S. aureus?= Hospital workers Which occupation has a high number of carriers= of S. aureus?= Hospital workers Question 6 of 64Question 7 of 64 What is S. aureus one of the major causes of? Hospital acquired infections What is S. aureus one of the major causes of? Hospital acquired infections Question 7 of 64Question 8 of 64 How is S. aureus transmitted?= Human to human How is S. aureus transmitted?= Human to human Question 8 of 64Question 9 of 64 What is a survival characteristic of S. aureus?= Can survive on dry surfaces for long periods (capsule) What is a survival characteristic of S. aureus?= Can survive on dry surfaces for long periods (capsule) Question 9 of 64Question 10 of 64 How many S. aureus are resistant to penicillin?= 95% How many S. aureus are resistant to penicillin?= 95% Question 10 of 64Question 11 of 64 Which gene makes them resistant?= β lactamase gene Which gene makes them resistant?= β lactamase gene Question 11 of 64Question 12 of 64 What other resistant strains of S. aureus are there (besides MRSA)?= (2) VSRA, HA-MRSA (hospital acquired), CA-MRSA (community acquired) What other resistant strains of S. aureus are there (besides MRSA)?= (2) VSRA, HA-MRSA (hospital acquired), CA-MRSA (community acquired) Question 12 of 64Question 13 of 64 What are the steps to identify S. aureus? =(5) Gram stain (+ve are +ve, -ve are -ve), catalase (peroxide bubbles with catalase) test (staphylococci are +ve, streptococcal -ve), coagulase test (S. aureus clump), (novobiocin identifies other staphylococci), mannitol salt agar (staphylococci halodurant and ferments mannitol) What are the steps to identify S. aureus? =(5) Gram stain (+ve are +ve, -ve are -ve), catalase (peroxide bubbles with catalase) test (staphylococci are +ve, streptococcal -ve), coagulase test (S. aureus clump), (novobiocin identifies other staphylococci), mannitol salt agar (staphylococci halodurant and ferments mannitol) Question 13 of 64Question 14 of 64 What virulence factors do S. aureus have?= (7) Adhesins, invasins, cytolysis, spreading factors, immunopathogenic factors, immune evasion factors. What virulence factors do S. aureus have?= (7) Adhesins, invasins, cytolysis, spreading factors, immunopathogenic factors, immune evasion factors. Question 14 of 64Question 15 of 64 What adhesins do S. aureus have?= MSCRAMMs (microbial surface components recognising adhesive matrix molecules) What adhesins do S. aureus have?= MSCRAMMs (microbial surface components recognising adhesive matrix molecules) Question 15 of 64Question 16 of 64 What do MSCRAMMs bind to? =(2) Cell walls, proteins (fibronectin, laminin, elastin) What do MSCRAMMs bind to? =(2) Cell walls, proteins (fibronectin, laminin, elastin) Question 16 of 64Question 17 of 64 What cytolysins do S. aureus have?= (4) Alpha toxin, beta toxin, delta toxin, gamma toxin What cytolysins do S. aureus have?= (4) Alpha toxin, beta toxin, delta toxin, gamma toxin Question 17 of 64Question 18 of 64 How does alpha toxin affect cells?= Form pores in cell, osmotic lysing How does alpha toxin affect cells?= Form pores in cell, osmotic lysing Question 18 of 64Question 19 of 64 How does beta toxin affect a host cell?= Hydolyses shimgomyelines in membranes How does beta toxin affect a host cell?= Hydolyses shimgomyelines in membranes Question 19 of 64Question 20 of 64 How does delta toxin affect a host cell?= Detergent like action How does delta toxin affect a host cell?= Detergent like action Question 20 of 64Question 21 of 64 How does gamma toxin affect a host cell?= Form pores in conjunction with other toxins How does gamma toxin affect a host cell?= Form pores in conjunction with other toxins Question 21 of 64Question 22 of 64 What cells are the cytolysins of S. aureus toxic to?= (3) Leukocytes, erythrocytes, tissue cells What cells are the cytolysins of S. aureus toxic to?= (3) Leukocytes, erythrocytes, tissue cells Question 22 of 64Question 23 of 64 Why do S. aureus destroy leukocytes?= Immune evasion Why do S. aureus destroy leukocytes?= Immune evasion Question 23 of 64Question 24 of 64 Why do S. aureus destroy erythrocytes?= Gain access to iron Why do S. aureus destroy erythrocytes?= Gain access to iron Question 24 of 64Question 25 of 64 Why do S. aureus destroy tissue cells?= Promote bacterial spreading Why do S. aureus destroy tissue cells?= Promote bacterial spreading Question 25 of 64Question 26 of 64 What is an exfoliative toxin?= Toxins that lift the outer layers of the skin and cause peeling What is an exfoliative toxin?= Toxins that lift the outer layers of the skin and cause peeling Question 26 of 64Question 27 of 64 How do ETA and ETB lift the skin =By destroying desmosomes in the stratum granulosum epidermis How do ETA and ETB lift the skin =By destroying desmosomes in the stratum granulosum epidermis Question 27 of 64Question 28 of 64 Which spreading factors so S. aureus have? =(5) Lipases, nucleases, hyaluronidase, proteases, staphylokinase (fibrinolysin) Which spreading factors so S. aureus have? =(5) Lipases, nucleases, hyaluronidase, proteases, staphylokinase (fibrinolysin) Question 28 of 64Question 29 of 64 How does the body react to invasion of bacteria?= Inflammatory response forms clot around site of infection to contain bacteria How does the body react to invasion of bacteria?= Inflammatory response forms clot around site of infection to contain bacteria Question 29 of 64Question 30 of 64 Which spreading factor allows the bacteria to escape clots?= Staphylokinase Which spreading factor allows the bacteria to escape clots?= Staphylokinase Question 30 of 64Question 31 of 64 What immunopathogenic factors does S. aureus have? =(2) Toxic shock syndrome toxin, staphylococcal enterotoxins What immunopathogenic factors does S. aureus have? =(2) Toxic shock syndrome toxin, staphylococcal enterotoxins Question 31 of 64Question 32 of 64 Which pro inflammatory cytokines do superantigens stimulate release of?= (2) TNF-alpha, IFN-gamma Which pro inflammatory cytokines do superantigens stimulate release of?= (2) TNF-alpha, IFN-gamma Question 32 of 64Question 33 of 64 How do superantigens work?= Unspecific, overstimulation of immune response How do superantigens work?= Unspecific, overstimulation of immune response Question 33 of 64Question 34 of 64 What immune evasion factors do S. aureus have? =(6) Capsule, slime layer, catalase, clumping factor, protein A What immune evasion factors do S. aureus have? =(6) Capsule, slime layer, catalase, clumping factor, protein A Question 34 of 64Question 35 of 64 How does a capsule promote immune evasion? =(2) Prevents opsonisation, contains water preventing desiccation How does a capsule promote immune evasion? =(2) Prevents opsonisation, contains water preventing desiccation Question 35 of 64Question 36 of 64 What is a capsule made of?= Dense polysaccharide coat What is a capsule made of?= Dense polysaccharide coat Question 36 of 64Question 37 of 64 How does a slime layer promote immune evasion? =(3) Helps bacteria adhere to surfaces, aggregates bacteria, protects from immune factors and antibiotics How does a slime layer promote immune evasion? =(3) Helps bacteria adhere to surfaces, aggregates bacteria, protects from immune factors and antibiotics Question 37 of 64Question 38 of 64 Where are biofilms a major concern? =On catheters and medical devices Where are biofilms a major concern? =On catheters and medical devices Question 38 of 64Question 39 of 64 How does catalase promote immune evasion?= Detoxifies peroxide produced by macrophages and neutrophils How does catalase promote immune evasion?= Detoxifies peroxide produced by macrophages and neutrophils Question 39 of 64Question 40 of 64 How does clumping factor promote immune evasion?= Binds fibrinogen and converts to fibrin (blood clot) cloaking itself with it which camouflages bacteria How does clumping factor promote immune evasion?= Binds fibrinogen and converts to fibrin (blood clot) cloaking itself with it which camouflages bacteria Question 40 of 64Question 41 of 64 How does protein A promote immune evasion?= Bind antibodies in wrong orientation preventing opsonisation and phagocytosis How does protein A promote immune evasion?= Bind antibodies in wrong orientation preventing opsonisation and phagocytosis Question 41 of 64Question 42 of 64 What superficial skin diseases do S. aureus =cause? =(4) Boils, impetigo, folliculitis What superficial skin diseases do S. aureus =cause? =(4) Boils, impetigo, folliculitis Question 42 of 64Question 43 of 64 What invasive diseases does S. aureus cause? (3) Pneumonia, endocarditis, bateremia What invasive diseases does S. aureus cause? (3) Pneumonia, endocarditis, bateremia Question 43 of 64Question 44 of 64 What invasive diseases does S. aureus cause? (3) Pneumonia, endocarditis, bateremia What invasive diseases does S. aureus cause? (3) Pneumonia, endocarditis, bateremia Question 44 of 64Question 45 of 64 What toxigenic disease does S. aureus cause?= (3) Food poisoning, scalded skin syndrome, toxic shock What toxigenic disease does S. aureus cause?= (3) Food poisoning, scalded skin syndrome, toxic shock Question 45 of 64Question 46 of 64 What is impetigo?= Localised cutaneous infection with pus filled vesicles What is impetigo?= Localised cutaneous infection with pus filled vesicles Question 46 of 64Question 47 of 64 What is folliculitis?= Impetigo involving hair follicles What is folliculitis?= Impetigo involving hair follicles Question 47 of 64Question 48 of 64 What are boils/furuncles?= Painful pus-filled cutaneous nodules What are boils/furuncles?= Painful pus-filled cutaneous nodules Question 48 of 64Question 49 of 64 What are carbuncles?= Coalescence of funcuncles can lead to systemic disease What are carbuncles?= Coalescence of funcuncles can lead to systemic disease Question 49 of 64Question 50 of 64 What are corneal ulcers?= Deep infection of the cornea What are corneal ulcers?= Deep infection of the cornea Question 50 of 64Question 51 of 64 What is the difference between aspiration and hematogenous spread?= Aspiration is infection through respiratory route, hematogenous is to the lungs through the blood What is the difference between aspiration and hematogenous spread?= Aspiration is infection through respiratory route, hematogenous is to the lungs through the blood Question 51 of 64Question 52 of 64 What causes necrotising pneumonia?= Tissue is damaged due to cytolytic toxins from S. aureus? What causes necrotising pneumonia?= Tissue is damaged due to cytolytic toxins from S. aureus? Question 52 of 64Question 53 of 64 What is osteomyelitis?= Hematogenous dissemination to bone What is osteomyelitis?= Hematogenous dissemination to bone Question 53 of 64Question 54 of 64 What is septic arthritis?= Infection in synovial fluid What is septic arthritis?= Infection in synovial fluid Question 54 of 64Question 55 of 64 What is bacteremia?= Spread of bacteria into the blood What is bacteremia?= Spread of bacteria into the blood Question 55 of 64Question 56 of 64 What is endocarditis?= Damage to endothelial lining of the heart or heart valves (biofilms, platelets, cytotoxins) What is endocarditis?= Damage to endothelial lining of the heart or heart valves (biofilms, platelets, cytotoxins) Question 56 of 64Question 57 of 64 What is the mortality rate of endocartitis due to S. aureus?= 50% What is the mortality rate of endocartitis due to S. aureus?= 50% Question 57 of 64Question 58 of 64 How does S. aureus cause toxigenic disease?= Toxins (SEA, SEB) produced by S. aureus cause disease (food poisoning) How does S. aureus cause toxigenic disease?= Toxins (SEA, SEB) produced by S. aureus cause disease (food poisoning) Question 58 of 64Question 59 of 64 What is staphyloccol scalded skin syndrome?= Exfoliative toxins cause cutaneous blisters and desquamation of epithelium What is staphyloccol scalded skin syndrome?= Exfoliative toxins cause cutaneous blisters and desquamation of epithelium Question 59 of 64Question 60 of 64 What are the symptoms of toxic stress syndrome?= Caused by super antigens which overstimulate immune response releasing large amounts of TNF, IL-1, fever, hypertension, rash, intravascular coagulation, organ failure, death What are the symptoms of toxic stress syndrome?= Caused by super antigens which overstimulate immune response releasing large amounts of TNF, IL-1, fever, hypertension, rash, intravascular coagulation, organ failure, death Question 60 of 64Question 61 of 64 What is the cause of menstrual toxic shock syndrome? =Toxic shock syndrome toxin that penetrate mucosal barrier What is the cause of menstrual toxic shock syndrome? =Toxic shock syndrome toxin that penetrate mucosal barrier Question 61 of 64Question 62 of 64 What are the treatments for S. aureus? =(3) Augmentin, flucloxacillin, vancomycin What are the treatments for S. aureus? =(3) Augmentin, flucloxacillin, vancomycin Question 62 of 64Question 63 of 64 Who are susceptible for S. aureus infection?= Infants, children with poor hygiene, mentruating women, patients with intravascular catheters, compromised pulmonary function, immunocompromisied patients, diabetics Who are susceptible for S. aureus infection?= Infants, children with poor hygiene, mentruating women, patients with intravascular catheters, compromised pulmonary function, immunocompromisied patients, diabetics Question 63 of 64Question 64 of 64 What are risk factors for infection of S. aureus? =(5) Foreign body (splinter, catheter), surgical procedures, poor hospital hygiene, suppressed microbial flora, lack of protective antibodies What are risk factors for infection of S. aureus? =(5) Foreign body (splinter, catheter), surgical procedures, poor hospital hygiene, suppressed microbial flora, lack of protective antibodies Question 64 of 64 Loading...
