[48] Impetigo

Question 1

What is impetigo?

Answer 1

A localised, highly contagious, staphylococcal or streptococcal skin infection

Question 2

Who is impetigo most common in?

Answer 2

Infants and young children

Question 3

What can impetigo be divided into?

Answer 3

Bullous and non-bullous forms

Question 4

Which type are the majority of impetigo cases?

Answer 4

Non-bullous

Question 5

What are the common causative organisms of non-bullous impetigo?

Answer 5

• Stahpylococcus aureus

- Streptococcus pyogenes

Question 6

What is an increasingly common cause of non-bullous impetigo?

Answer 6

MRSA

Question 7

What is bullous impetigo most commonly caused by?

Answer 7

Staph aureus

Question 8

What are the risk factors for impetigo?

Answer 8

• Pre-existing skin disease e.g. eczema
• Poor hygiene
• Breach in skin e.g. bites, trauma, chickenpox

Question 9

How does non-bullous impetigo present?

Answer 9

Tiny pustules or vesicles that evolve rapidly into honey coloured plaques under 2cm in diameter

Question 10

Where does non-bullous impetigo typically affect?

Answer 10

The face but also on extremities where skin breaks have occured

Question 11

What may surround a non-bullous impetigo lesion?

Answer 11

Satellite lesions due to autoincoulation

Question 12

What secondary symptoms may be present in non-bullous impetigo?

Answer 12

• Itching

- Regional lymphadenopathy

Question 13

How does bullous impetigo appear?

Answer 13

Thin roofed bullae that rupture spontaneously with little eryhtema

Question 14

Where does bullous impetigo typically affect?

Answer 14

Face, trunk, extremities, buttocks or perineal regions

Question 15

What secondary symptoms might present with bullous impetigo?

Answer 15

• Painful

- Malaise

Question 16

How is impetigo typically diagnosed?

Answer 16

Clinically

Question 17

When might swabs and cultures be necessary in impetigo?

Answer 17

• Extensive or severe
• MRSA suspected
• Recurrent or not responding to treatment

Question 18

What are the differentials fo impetigo?

Answer 18

• Contact dermatitis
• Scabies
• Various viral skin infections e.g. herpes, VZV
• Atopic eczema
• Burns
• Stevens Johnson Syndrome

Question 19

What are the general advice measures in impetigo?

Answer 19

• Stay off school until lesions are dry and scabbed
• Keep area clean
• Wash hands
• Avoid sharing towels

Question 20

What medication can be helpful in some mild cases?

Answer 20

Topical antibiotics e.g. mupirocin

Question 21

When are oral antibiotics required?

Answer 21

In severe cases that are extensive or resistant to treatment

Question 22

Which type of impetigo usually requires oral antibiotics?

Answer 22

Bullous

Question 23

What are the potential complications of impetigo?

Answer 23

• Cellulitis
• Lymphangitis
• Staphylococcal scaled skin syndrome

Question 24

What complications may arise if the causative organism is group A beta haemolytic streptococcus?

Answer 24

• Scarlet fever

- Glomerulonephritis