Skin and soft tissue

Question 1

What are the common causative organisms of cellulitis?

Answer 1

Beta-haemolytic Strep (70-85%)
Staphylococcus aureus (10%) higher if purulent
Gram negative organisms (<1%)

Question 2

What factors are associated with a higher risk of gram negative cellulitis?

Answer 2

1. Immunocompromised
2. Diabetics
3. Abdominal wall infections
4. Cirrhotics

Question 3

What organisms are associated with cat and dog bites?

Answer 3

Pasturella, Capnocytophagia

Question 4

What organisms are associated with marine exposure related cellulitis?

Answer 4

Vibrio / aeromonas species

Question 5

What percentage of those diagnosed with cellulitis have a cellulitis-mimic?

Answer 5

30%

Question 6

What factors are suggestive of necrotising fasciitis?

How is it diagnosed?

Answer 6

Surgical exploration

1. Toxic shock (50%)
2. "sicker than cellulitis"
3. Pain out of proportion
4. Purplish discoloration
5. Violaceous bullae 
6. Crepitus
7. LRINEC score
    8. MRI findings

Question 7

What is the role for clindamicin in treatment of cellulitis?

Answer 7

Only useful if sepsis is present

Question 8

What percentage of cellulitis was self resolving in the pre-antibiotic era?

Answer 8

70%

Question 9

Are oral or IV antibiotics superior in the treatment of cellulitis?
What are indications for inpatient treatment?

Answer 9

Equivalent for most patients (IVs for those with sepsis)

Consider treating those with PVD (arterial or venous), obesity, heart failure, immunosuppression in hospital setting

Question 10

PATCH1 trial

• outcome
• NNT

Answer 10

Utility of prophylactic abx for recurrent cellulitis
Favours use of pen VK 250mg BD
NNT = 5

Question 11

What percentage of people have residual inflammation after

• completion of abx
• 3 weeks following completion of abx?

Answer 11

• 60%

- 40%