8 - Derm - Bacterial infections - Primary staph/strep infections - Cellulitis, Erysipelas, Ecthyma

Question 1

cellulitis - cause? what happens? why? occasional gives?

Answer 1

usually GAS
hot tender redness - subcut infection
oedema and blistering

Question 2

cellulits - if left untreated? usually where? look for what O/E?

Answer 2

prog to deeper layers > necrotising fasciitis

lower leg

look for trauma, insect bites

Question 3

Cellulitis - Ix? mgmt?

Answer 3

swabs if obvious portal of entry, serological testing more reliable (ASO titre)

penicillin, flucloxacillin or erythromycin

Question 4

cellulitis complications - 7

Answer 4

septicaemia, skin necrosis, necrotising fasciitis, abscesses, lymphoedema, myocarditis/renal failure due to toxins

Question 5

erysipelas - usual pathogen? in infants? affects where?

Answer 5

GAS, H. influenzae in infants

superficial infection - usually affects face

Question 6

erysipelas - appearance? Ix

Answer 6

well defined, raised, painful erythema

Ix - swabs of any other affected sites (throat, nose etc)

Question 7

erysipelas - mgmt + complications

Answer 7

benzylpenicillin

chronic facial lymphoedema + recurrent cellulitis
orbital cellulitis > meningitis

Question 8

Ecthyma - pathogens? appearance?

Answer 8

staph/strep/mixed

chronic well demarcated deeply ulcerative lesions with exudative crust

Question 9

ecthyma - usually where? mgmt?

Answer 9

commonly lower legs buttocks and thighs

mgmt - erythromycin, fluclox, clindamycin