3. Staph

Question 1

Staph aureus suppurative diseases

Answer 1

	Skin infections – impetigo (honey crusted), furuncles, cellulitis, blepharitis
	Sepsis
	Abscesses 
	Endocarditis of heart valves
	Osteomyelitis and arthritis
	Post op/post viral infection pneumonia

Question 2

Staph aureus toxin mediated diseases

Answer 2

 Food poisoning – sx 1-8 hrs after ingestion
 TSS – fever, hypotension, diffuse rash, 3 organ involvement
 Scalded skin syndrome – children, bullae, fever, rash

Question 3

Staph aureus exotoxins

Answer 3

 Enterotoxin – heat stable superantigen – food poisoning w/ vom & non bloddy diarrhea
 TSST – superantigen – TSS
 Exfoliative toxin – serine proteases that act on cell adhesion molecule in desmosomes – scalded skin syndrome
 Α, β, δ, γ toxins – lysis of RBCS and neutrophils
 Panton-Valentine leukocidin – lyses WBCs.

Question 4

Staph aureus treatment abx

Answer 4

• MRSA: vancomycin

- penicillin resistant stain - nafcillin, oxacillin

Question 5

Staph aureus xteristics

Answer 5

B hemolytic, catalase +, coagulase +, ferments mannitol

Question 6

Staph aureus virulence factors

Answer 6

protein A, teichoic acid, polysaccharide capsule, exotoxins, enzymes

Question 7

Staph epidermidis xteristics

Answer 7

G hemolytic, catalase +, coagulase -, novobiocin sensitive

Question 8

Staph epidermidis diseases

Answer 8

o Joint infections
o Infection of prosthetic implants and catheters
o Endocarditis
o Neonatal sepsis

Question 9

Staph epidermidis & Staph saprophyticus virulence factor

Answer 9

o Gram + cell wall components: teichoic acid. Some may have glycocalyx
o No exotoxins

Question 10

Staph saprophyticus xteristics

Answer 10

G hemolytic, catalase +, coagulase -, novobiocin resistant

Question 11

Staph saprophyticus diseases

Answer 11

UTIs in sexually active women

Question 12

Vaccine availability

Answer 12

No vaccines for any of the 3 import staphs

Question 13

Staph saprophyticus treatment

Answer 13

quinolone or trimethoprim-sulfamethoxazole

Question 14

Staph epidermidis treatment

Answer 14

Vancomycin, removal of infected devices