Causative agents in infections

Question 1

bullous impetigo

Answer 1

staph aureus

Question 1

non-bullous impetigo

Answer 1

staph aureus

group A beta-hemolytic strep (strep pyogenes)

Question 2

most common cause of folliculitis

Answer 2

Gram + staphylococcus aureus

Question 3

gram positive bacterial folliculitis

locations

Answer 3

staphylococcus aureus
-scalp and face

MRSA
-chest, flanks, scrotum, periumbilical

Question 4

gram negative bacterial folliculitis

Answer 4

pseudomonas (hot tub folliculitis)
-eruption begins 8-48hrs after exposure

can also be
-klebsiella, enterobacter, proteus

more common in patients on long term antibiotics

Question 5

fungal folliculitis

Answer 5

malassezia (pityrosporum)
-monomorphic follicular papules and pustules
-chest, back, arms

dermatophyte
-follicular pustules surrounded by erythematous plaque

candida

Question 6

furuncles and carbuncles

Answer 6

S. aureus (both MRSA and MSSA)

can also be E. Coli, P. aeruginosa, S. fecalis

Question 7

cellulitis

Answer 7

beta-hemolytic streptococci

Question 8

erysipelas

Answer 8

beta-hemolytic streptococci

Question 9

periorbital cellulitis

Answer 9

S. aureus, S. pneumoniae, S. pyogenes

Question 10

SSSS (staphylococcal scalded syndrome)

Answer 10

staphylococcus