Skin + Soft tissue Infections

Question 1

what is erysipelas?

Answer 1

infection of the upper dermis

Question 2

causative organism of erysipelas?

Answer 2

strep. pyogenes

Question 3

clinical features of erysipelas?

Answer 3

• mostly occurs in face and limbs
• raised erythematous area
• systemically unwell; fever etc

Question 4

what is cellulitis?

Answer 4

infection in the deep dermis and subcutaneous fat layer

Question 5

clinical features of cellulitis?

Answer 5

• spreading erythematous area with no borders
• fever

Question 6

causative organism of cellulitis?

Answer 6

50/50 staph or strep

Question 7

treatment of cellulitis?

Answer 7

flucloxacillin

Question 8

outline the 3 hair associated infections

Answer 8

• folliculitis
• furunculosis
• carbuncles

Question 9

what is folliculitis?

Answer 9

pustular infection of a single hair follicle

Question 10

clinical features of folliculitis and most likely causative organism?

Answer 10

• red papules visible
• usually occur on head, buttocks and extremities
• staph aureus

Question 11

what is furunculosis?

Answer 11

inflammatory infection of a single hair follicle

Question 12

clinically in furunculosis? most likely causative organism?

Answer 12

• may spontaenously drain
• may extend into dermis/ subcutaneous layer
• staph aureus

Question 13

what is a carbuncle?

Answer 13

an abscess encomapssing many adjacent hair follicles

Question 14

clinically with a carbuncle?

Answer 14

systemically unwell

Question 15

treatment of carbuncle?

Answer 15

antibiotics & surgery

Question 16

what are the types of necrotising fasciitis?

Answer 16

1. Mixed anaerobes and aerobe infection
   - requires urgent surgery
2. Monomicrobial
   - strep pyogenes

Question 17

what is seen clinically in necrotising fasciitis?

Answer 17

• sequential progression of
  
  • erythema
  • oedema
  • unremitting pain
  • haemorrhagic bullae
  • skin necrosis
  • • systemic symptoms ie hypotension

Question 18

treatment of necrotising fasciitis?

Answer 18

broad-spectrum antibiotics

• gentamicin/ fluclox / clindamycin

Question 19

what is pyomyositis?

Answer 19

this is an abscess formation within a muscle

Question 20

clinically in pyomyositis?

Answer 20

• systemic symptoms ie fever, pain
  
  • if untreated, can lead to septic shock
• must investigate with MRI/ CT

Question 21

causative organism & treatment of pyomyositis?

Answer 21

• s.aureus
• antibiotics + drainage

Question 22

how may you get septic bursitis?

Answer 22

spread from adjacent infection

Question 23

ddx of septic bursitis and how can you distinguish ?

Answer 23

septic arthritis

get patient to bend knee and if relatively painless, most likely NOT septic arthritis

Question 24

clinically in septic bursitis?

Answer 24

• swollen
• warmth
• erythema
• fever

Question 25

diagnosis of septic bursitis? most common causative organism?

Answer 25

* diagnosis --\> aspiration of fluid * staph aureus

Question 26

what is infectious tenosynovitis?

Answer 26

infection of the synovial sheath surrounding tendons

Question 27

where does infectious tenosynovitis usually arise? most common causative organism?

Answer 27

* usually in the common flexor tendons of the hand * staph aureus

Question 28

clinically in infectious tenosynovitis?

Answer 28

* swelling of finger * held in semi flexed positon

Question 29

treatment of infectious tenosynovitis?

Answer 29

antibiotics and surgery

Question 30

what are toxin-mediated syndromes caused by?

Answer 30

superantigens which release pyogenic endotoxins, which attach directly to T cells

Question 31

what does toxin 1 cause?

Answer 31

* causes toxic shock syndrome (staph & strep) * fever * hypotension * rash * organ failure

Question 32

what is staphylococcal scalded skin syndrome caused by? - what are the symptoms - in what age group does it usually occur

Answer 32

by exotoxins of staph aureus- toxins A & B * widespread bullae * skin exfoliation * fever * mostly occurs in \<5's

Question 33

venflon-associated infections are usually caused by what organisms?

Answer 33

* MRSA * methicillin sensitive staph aureus