Micro - Gram Positive Bacteria III

Question 1

3 major pathogenic staph species

Answer 1

staph aureus
staph epidermidis
staph saprophyticus

Question 2

gold pigment when cultured on sheep blood agar

Answer 2

staph aureus**

-differentiated from other beta-hemolytic cocci

Question 3

coagulase positive

Answer 3

only staph aureus

-ultimately causes blood to clot

Question 4

coagulase negative

Answer 4

staph epidermidis

staph saprophyticus

Question 5

staph proteins

Answer 5

protein A - protect from phagocytosis
coagulase - protect from phagocytosis
hemolysins - destroy blood cells
leukocidins - destroy leukocytes
penicillinase - disrupts portion of penicillin
novel penicillin binding protein - for peptidoglycan formation

Question 6

panton-valentine leukocidin

Answer 6

produced by CA-MRSA

-gives ability to form abscesses

Question 7

more staph proteins

Answer 7

hyaluronidase
staphylokinase
lipase
protease

Question 8

staph aureus exotoxins

Answer 8

exfoliatin
enterotoxin
TSST-1 - superantigen

Question 9

scalded skin syndrome exotoxin

Answer 9

exfoliatin

-staph aureus

Question 10

exotoxin release disease from staph aureus

Answer 10

gastroenteritis - food poison
TSS
scalded skin syndrome

Question 11

direct organ invasion from staph aureus

Answer 11

pneumonia
meningitis
osteomyelitis
acute bacterial endocarditis
septic arthritis
skin infections
bacteremia/sepsis
UTI

Question 12

gastroenteritis

Answer 12

food poisoning
-staph produce exotoxin in food

nausea, vomiting, diarrhea, abdominal pain - 12-24 hours

Question 13

toxic shock syndrome

Answer 13

staph auresus - TSST-1

-increases TNF an IL-1

Question 14

acute high fever, nausea, vomiting, diarrhea, followed by diffuse erythematous rash with desquamation of palms and soles

Answer 14

toxic shock syndrome
-staph aureus

also septic shock

Question 15

staph scalded skin syndrome

Answer 15

staph aureus - exfoliative toxin A and B
-neonates with local infection of recently severed mubilicus or older children with skin infections

most rule out drug allergy

Question 16

bone infection in boys under 12 year old

Answer 16

osteomyelitis due to staph aureus

Question 17

sudden high fever, chills, myalgias

Answer 17

acute endocarditis

staph aureus

Question 18

disease from staph due to exotoxin release

Answer 18

gastroenteritis
TSS
scalded skin syndrome

Question 19

diseases from staph due to organ damage

Answer 19

pneumonia
osteomyelitis
acute endocarditis
septic arthritis
skin infection
blood and catheter infections

Question 20

pneumonia following viral influenza in hospitalized patient
-abrupt onset of fever, c chills, lobar consolidation of lung, rapid destruction of parenchyma, cavitations in lung, effusion and empyema

Answer 20

staph aureus - rare cause of pneumonia

Question 21

IV drug users

Answer 21

develop right sided tricuspid valve endocarditis and may present with pneumonia caused by bacterial embolization

-staph aureus - rapid onset

Question 22

septic arthritis

Answer 22

infection of synovial membrane with staph aureus

Question 23

most common pathogen causing septic arthritis in pediatric age group and adults over age 50

Answer 23

staph aureus

Question 24

skin infections

Answer 24

almost exclusively caused by strep pyogenes or staph aureus

-difficult to differentiate

Question 25

impetigo

Answer 25

infection on face around moth - small vesicles lead to pustules - crust over, honey colored, wet, flaky staph aureus

Question 26

cellulitis

Answer 26

deep infection of cells -tissue - hot, red, shiny, swollen staph aureus

Question 27

abscess

Answer 27

collection of pus

Question 28

furuncle

Answer 28

follicle infection penetrates to subQ tissue

Question 29

carbuncle

Answer 29

furuncles that communicate under the skin

Question 30

MRSA

Answer 30

methicillin resistant staph aureus - acquired chromosomal DNA segment mecA - encodes penicillin binding protein 2A vancomycin - useful antibiotic against MRSA -however, now becoming resistant

Question 31

CA-MRSA

Answer 31

community acquired methicillin resistant staph aureus carries PVL gene encoding methicillin resistance - SCCmec -CA-MRSA better at spreading SCCmec

Question 32

predominant methicillin resistant staph bacterium in and outside the hospital

Answer 32

CA-MRSA

Question 33

staph epidermidis

Answer 33

normal bacterial flora -coagulase negative active in compromised hospital patients with foley catheters or IV lines also frequent skin contaminant of blood cultures

Question 34

infection of prosthetic devices

Answer 34

staphylococcus epidermidis forms biofilms on catheters

Question 35

staph saprophyticus

Answer 35

second leading cause of UTIs -sexually active young women coagulase negative

Question 36

UTI in sexually active women

Answer 36

staph saprophyticus gram positive cocci in clusters catalase positive coagulase negative