Set3

Front 1

who are at risk for Staph. aureus?

Back 1

-new borns
-ppl already with some underlying disease
-drug abusers
-burn patients
-trauma patients

Front 2

what are the diseases caused by Staph. aureus? primary vs. severe

Back 2

-primary: boils, wound infection, infection originating from prosthetic devices
-severe: sepsis, endocarditis, osteomyelitis, pneumonia, toxic shock syndrome, post-op infection

Front 3

what are the potential virulence determinants of staph. aureus?

Back 3

- cell associated proteins: protein A, capsular polysacc., peptidoglycan (complement --> inflammation --> damage to adjacent cells), adhesion proteins (MSCRAMMs: fibronectin-binding proteins A & B, fibrinogen-biding protein, collagen-binding protein)
- exozymes: coagulase, lipase, hyaluronate lyase, nuclease, staphylokinase, protease
- exotoxins: tss-1, epidermolytic toxin(alpha, beta, chi, gamma), leukocidin, enterotoxins (A-E)

Front 4

what are the two ways in which Staphylococcus causes disease?

Back 4

- inflammatory. local: boils or furuncles fuse together to form carbuncles. pus contains neutrophils, staph, host cells, DNA (gives it thickness)
- toxigenic diseases: staph scalded skin syndrome, staphylococcal food poisoning (enterotoxin)... within 1-6 hrs. toxic shock syndrome (women died ... tampon story.)

Front 5

what antibiotics do you give for Staph. Aureus?

Back 5

vancomycin-intermediate strains began to appear in NY 2002. so linezolid (oxazolidinones) = protein synthesis inhibitors... resistance to this is RARE. you can also do daptomycin: lipopeptide (MB active)

Front 6

what are the diseases caused by GAS? (grp them based on classfication)

Back 6

suppurative diseases.
-nontoxigenic strains: primary (pharyngitis), secondary: otitis, pneumonia, meningitis
-toxigenic: scarlet fever (fever, rash), necrotizing fasciitis (A=superantigen, B=systemic protease ==> pyoderma)
also, adenitis (inflammation of glands, lymph nodes), skin infections: impetigo, cellulitis, erysipelas. also, puerperal sepsis (sepsis contracted by women shortly after childbirth or abortion), lymphangitis, endocarditis
nonsuppurative disease (poststreptococcal infections):
rheumatic fever, glomerularnephritis

Front 7

what are the criteria for Rheumatic fever?

Back 7

carditis, polyarthritis, chorea, subcutaneous nodules, rash

Front 8

what are the potential virulence determinants of GAS?

Back 8

- streptolysin (hemolysin)
- streptokinase (dissolves blood clots). don't use this for heart patients. use TPA instead (tissue plasminogen activator)
- hyaluronidase
- deoxyribonuclease
-erythrogenic toxin
- hyaluronic acid
- m-protein
-peptidoglycan
- lipoteichoic acid

Front 9

M-protein's role in pathogenesis. which bacteria has it?

Back 9

- strep A has it.
- proteolytic cleavage of M-protein. M-protein binds to fibrinogen --> binds to neutrophil (via beta-integrin). activated MP now does 2 things:
1)releases HBP ==> vascular leakage --> shock
2) frustrated MP --> proinflammatory mediators --> tissue damage

Front 10

what are the potential virulence determinants of GBS?

Back 10

- SA prevents opsonization by C3b, inhibits alternate pathway activation
- C5a peptidase: prevents chemotaxis
- capsule: protects bacteria
- beta-hemolysin/cytotoxin --> damages endothelial cells
- cell damage triggers inflammation

Front 11

what are the major diseases caused by Streptococcus pneumoniae?

Back 11

pneumonia, otitis medea (middle ear), meningitis

Front 12

what are the risk factors in streptococcal pneumoniae infection?

Back 12

age: extreme age (<2 or > 60)
acute and chronic ailments: influenza, heart failure, bronchitis/emphysema/ashtma/cancer, immune suppression (AIDS)
environmental irritants: smoking; air pollution
alcoholic intoxication: decr -> cough reflec; decre -> phagocytic response
impairement of spleen does this too.

Front 13

what are the virulence factors of strep. pneumoniae?

Back 13

-capsule, surface protein A: protects from PC
-IgA protease
-pneumolysin: cytotoxin; damages other cells too by complement/inflammation
-hydrogen peroxide
-dif types of poly sacc. capsules (~23 dif types)
-protease sensitive surface component: binds factor H; inhibits complement activation
-murein
-neuraminidase
-adhesin
-CWPS

Front 14

how is corynebacterium diphtheriae transmitted? what does it do?

Back 14

by inhalation.
causes pharyngitis or bronchitis: inflammation & toxin production. Two things from here: 1) pseudomembrane --> respiratory obstruction or 2) toxemia --> CNS, heart, kidney

Front 15

what is the antibiotic treatment for c. difficile

Back 15

flagyl (metronidazole) ==> selective for anaerobic bacteria and protozoan. reduces its nitro grp to ferrodoxin --> damages DNA --> inhibits nucleic acid synthesis. If this doesn't work, use vancomycin.