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40 Cards in this Set
- Front
- Back
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What is the classification of Streptococcus?
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-Gram positive
-facultative -arrange in chains -hemolysis -Lancefield (group A) |
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Explain Strep vs. Staph
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strep:chains
staph:clusters -both are catalase |
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Why is S.Pyogenes so sucessful as a pathogen
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because of it's ability to colonize, multiply, and spread, while evading phagocytosis and confusing the immune system.
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What components make up S.Pyogenes?
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-group A carbohydrates
-beta-hemolytic -capsule -M protein |
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What is the role of protein G
and C5 peptidase? |
it binds to the wrong end of an antibody.
-C5 pep: inhibits C5 used for inflammation |
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What are 2 adherence factors of Strep
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-lipoteichoic acid (makes them sticky and interact with fibronectin.)
-Protein F (also binds to fibronectin) |
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What is the importance of Streptokinase?
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-it dissolves blood clots
-this aids the bacteria to enter the host by dissolving clots created by the body to block entrance |
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What toxins are produce by strep.
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Pyrogenic exotoxins
(fever producing) |
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How does "Streptolysin O" aid in the spread of Strep bacteria?
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It forms pores in leukocytes,tissue and platelets.
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What is Streptococcal pharyngitis?
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-S.Pyogenes
-group A -Beta-hemolytic -and it is supperative(pus) |
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Why isn't there a vaccine for Streptococcal Pharyngitis?
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Because there are 100's of M-proteins and that means you would have to get all of them approved by the FDA (unlikely)
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What are two nonsupperative Strep. diseases?
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-Acute Rheumatic fever
-Acute glomerulonephritis |
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How do you get Rheumatic fever?
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Your body builds an immune to M-proteins and since these proteins are in the heart then you can send Ab to your heart thus activating the completment system(inflammation and heart disease)
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Why is a Rheumatic Fever recurrent in previously infected individuals.
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because the next time Ab will react even faster thus the complement system on the heart is faster. (life-long prophalaxsis is needed)
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What are the symtoms of Rheumatic Fever?
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Inflammation of various tissues including joints, heart, skin, and brain.
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What is the incubation period for rheumatic heart disease?
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1-4 weeks after a Strep throat infection
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How does Endocarditis occur in the heart?
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By the formation of clots in the heart thus giving bacteria a place to grow.
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what is the best step in the prevention of Rheumatic Heart Disease?
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Getting rid of the strep before your body starts an immune response.(which then complement immunity attacks the heart)
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What test are used to test for Strep?
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-Latex bead agglutination
-ELISA |
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How does an individual aquire Acute Glomerulonephritis
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By the activation of the complement system by bacterial components deposited on in the kidney
(second attacks are rare) |
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What is Scarlet Fever?
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-Streptococcal pharyngitis with a rash.
-Erythrogenic Toxin (reddening of tongue) |
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what kind of infection is Impetigo?
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Either a Staph.Aureus or a S.Pyogenes infection of the skin.(usually around the mouth)
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Why is Flesh-eating bateria so deadly and has little pus?
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Because it spreads so fast that there is little time for recruitment of luekocyctes and Ab's to the site.
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What is the estimated life expectancy of someone affected with a flesh-eating bacteria?
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24-48 hours
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What are the symptoms of Necrotizing Fascitis?
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-flu-like symptoms
-fever -pain (excruciating) |
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What is the treatment of Necrotizing Fascitis?
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Getting the infected tissue out of the body then treating with antibiotics.
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Discribe a Group B Strep and where is it found?
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-Stretococcus Agalactiae
-beta-hemolyptic -this colonize the lower GI and GU tracts |
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Why is S.Agalactiae so critcal in pregnant women?
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because it causes Neonatal sepsis and meningitis. Women screened in trimester.
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What is the difference in alpha and beta-Hemolysis?
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Alpha: incomplete hemolysis
beta: complete hemolysis |
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What is the form of S.Pneumoniae and how many varations are there of this form?
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-84 different versions of capsulated form
-alpha-hemolytic |
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How does S.Pneumonia occur in the body?
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When the normal colonization in the nose and throat spread to places they shouldn't.(due to increase in mucos secreations-cold)
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What is pneumococcol pneumonia?
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Community acquired pneumonia.
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What must bacteria overcome to multiply in the lungs?
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The alveolar macrophages
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How does Pneumococcal Pneumonia get into the lungs?
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-smoking
-alcohol(changes mucus) -old age(can't cough as much) Then they grow rapidly in the edema fluid |
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What other disease can occur from the traveling of bactria in the blood stream?
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-menigitits
-endocarditis -septic arthritis -sinusitis and otitis media |
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What is pathogenesis?
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disease cause by multiplication of bacteria in tissue.
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How do you test Pneumonia patients for bacteria?
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Sputum sample (need exudate)
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Typically what streps are found in the mouth?
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Viridans Strep
(greening strep) -subacute bacterial endocarditis |
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Name Group A Strep.
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-S.pyogenes
-S.pharyngitis |
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What strep is non groupable?
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S.Pneumoniae
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