Infections

Question 1

What is a furunculosis?

Answer 1

Acute deep infection of a hair follicle

Question 2

Which organism most commonly causes impetigo?

Answer 2

Staph aureus

Non bullous impetigo can also be caused by S pyogenes

Question 3

How does impetigo present?

Answer 3

Sore weepy yellow crusted areas on the face

Question 4

How should you treat impetigo?

Answer 4

Fucidic acid

Question 5

What is staphylococcal scaled skin syndrome?

Answer 5

Widespread staph infection leading to desquamation

Question 6

How does cellulitis present?

Answer 6

Usually a unilateral hot, tender, advancing red rash with systemic sings of infection

Question 7

How is necrotising fasciitis treated?

Answer 7

IV abx and urgent surgical debridement

Question 8

Which age group commonly gets SSSS?

Answer 8

<5yers

Question 9

What causes SSSS?

Answer 9

Epidermolytic toxins A and B bind to desmolgein 1 to prevent adherence of cells to the basal membrane

Question 10

How does SSSS present?

Answer 10

Fever, irritability and widespread erythema

Then fluid filled blisters which rupture easily

Question 11

How is SSSS investigated?

Answer 11

Smear
Biopsy
Bacterial culture of skin

Question 12

How is SSSS treated?

Answer 12

IV abx

Supportive measures

Question 13

Where is the infection in cellulitis?

Answer 13

Lower dermis and subcutaneous tissues

Question 14

What condition is essentially a more superficial cellulitis?

Answer 14

Erysipelas

Question 15

What organisms most commonly cause cellulitis?

Answer 15

S pyogenes

Staph aureus

Question 16

How is cellulitis treated?

Answer 16

Rest and elevate affected limb
IV abx

(unless u catch it early in which case there are so complications/systemic signs then oral abx is fine)

Question 17

How are viral warts treated?

Answer 17

Cryotherapy

Salicylic acid

Question 18

What can be given for moluscum prophylaxis?

Answer 18

Aciclovir

Question 19

What are the two main types of fungal infection?

Answer 19

Dermatophytes and yeast

Question 20

What is tinea incognito?

Answer 20

When tinea infection are misdiagnosed and treated with steroids they lose the annular appearance and present as tinea incognito

Question 21

How does tinea corporus present?

Answer 21

Singular annular patch on the body

Question 22

How does tinea capitus present?

Answer 22

Crusty patch, often large, often inflamed

on the head

Question 23

What is pityriasis versicolor?

Answer 23

A yeast infection of the skin causing flaky, discoloured patches to appear

Question 24

In which areas are patches found in pityriasis versicolor?

Answer 24

Trunk, neck and upper limbs

Question 25

True or false

Pityriasis is extremely itchy

Answer 25

False

Usually asymptomatic

Question 26

Which organism usually causes pityriasis versicolor?

Answer 26

Malassezia genus

M globosa
M restricta
M sympodialis

Question 27

How is fungal infection generally investigated?

Answer 27

Wood lamp
Microscopy
Fungal culture
Biopsy

Question 28

How is pityriasis versicolor treated?

Answer 28

Topical antifungal agents
(may come in cream, shampoo, etc)

Oral if extensive or persistent

Question 29

How are fungal infections generally treated?

Answer 29

Topical anti-fungals

Oral treatment if on nails or scalp

Question 30

True or false:

Topical treatments should be used in pityriasis versicolor until the white patches completely resolve

Answer 30

False

Sometimes the hypopigmentation persists after the infection despite sun exposure, and furthter treatment is unhelpful.