Skin Infections and Infestations

Question 1

Define infection

Answer 1

The pathological state resulting from the invasion of the body by pathogenic microorganisms

Question 2

Give some aerobic cocci that live on the skin

Answer 2

Staphylococcus epidermidis

Staphylococcus aureus

Question 3

What is a common test that lives on the skin?

Answer 3

Malassezia furfur

Question 4

What are some clinical signs of infection?

Answer 4

Erythema
Hot
Tender
Pus
Exudate
Fever

Question 5

What are some initial tests for skin manifestations?

Answer 5

Skin swabs for microscopy
Cultures
Sensitivity

Question 6

What further tests can be done for skin conditions if clinically indicated?

Answer 6

FBC
ESR
U&Es
LFTs
Serum calcium
CRP
Skin biopsy

Question 7

Is atopic eczema generally hot or tender?

Answer 7

No

Question 8

Are there generally any systemic symptoms associated with atopic eczema?

Answer 8

No

Question 9

Is atopic eczema generally exudative?

Answer 9

No

Question 10

What is impetigo?

Answer 10

A superficial bacterial skin infection that is the most common of its kind in children

Question 11

What are the two possible causative agents of impetigo?

Answer 11

Staph aureus

Strep pyogenes

Question 12

What is the treatment for localised impetigo?

Answer 12

Preferably Mupirocin 2% cream 3 times daily for 5 days if it MRSA, or Fusidic acid 2% cream 3-4 times for 5 days

Question 13

What is the treatment for widespread severe/bullous impetigo?

Answer 13

Flucloxacillin 500mg oral four times daily for 7 days

Erythromycin 500mg oral four times a day for 7 days

Question 14

What is the clinical challenge of cellulitis and erysipelas?

Answer 14

The two are very difficult to differentiate clinically, but this rarely has an impact on treatment

Question 15

What is often true of patients with cellulitis or erysipelas?

Answer 15

They are often very systemically unwell and may have fever or rigor

Question 16

What are the two likely causative organisms for celluilits/erysipelas?

Answer 16

Strep pyogenes

Staph aureus

Question 17

What is the treatment for cellulitis/erysipelas?

Answer 17

Flucloxacillin 1g IV every 6 hours

Benzylpenicllin 1.8g IV every 6 hours

If worried about the patient give both!

Question 18

What are the general management principles of a bacterial infection?

Answer 18

Take swab
Start antibiotics
Review after 48 hours
If not better in a week consider alternative diagnosis

Question 19

What are oedema blisters?

Answer 19

Acute exacerbations of oedema
Commonly found on the dorsum of the feet
Often erythematous
Can feel hot

Question 20

What is lipodermatosclerosis?

Answer 20

A very late presentation of eczema where much of the skin of the affected area is sclerosed. It is often bilateral

Question 21

What must be considered in patient with lipodermatosclerosis?

Answer 21

Look for signs of venous disease

Question 22

What is the treatment outline for lipodermatosclerosis?

Answer 22

Treat underlying venous disease

Topical steroids

Question 23

What are tinea infections?

Answer 23

A broad range of fungal infections. The term tinea is very general and the infection is usually defined by where it is affecting

Question 24

What is tinea of the head called?

Answer 24

Tinea capitis

Question 25

What is tinea of the foot called? What is a other name for this common infection?

Answer 25

Tinea pedis | Athlete's foot

Question 26

Why do fungal infections commonly fact the toes and nails?

Answer 26

Dermatocytes crave keratin

Question 27

What is the basic initial test principle for fungal infection?

Answer 27

Take skin scrapings

Question 28

What is the treatment for tinea infections of the feet, body, hands or groin? Which of the two creams is better at killing dermatocytes?

Answer 28

Usually respond to topical cream - Terbinafine or clotrimazole Clotrimazole

Question 29

What is the treatment for tinea infection of the scalp or nails?

Answer 29

Oral antifungals

Question 30

What are some differences between tinea infection and eczema?

Answer 30

History is relevant - fungal exposure? atopic? Distribution patterns differ Skin scraping will differentiate Eczema is very common, tinea corporis very rare Eczema is more itchy

Question 31

What is another name for candida albicans infection? Where does it common affect?

Answer 31

Thrush Vagina Breast creases Groin Mouth

Question 32

What is the treatment for candida albicans infection?

Answer 32

Nystatin Miconazole Ketoconazole

Question 33

What is an uncommon skin manifestation of HPV infection?

Answer 33

Warts

Question 34

Are warts contagious?

Answer 34

Yes but the risk of transmission is low

Question 35

What is molluscum contagiosum?

Answer 35

A DNA pox virus which presents with umbilicate papules May become secondarily infected Will resolve when the patient develops immunity

Question 36

How many main strands of herpes simplex virus (HSV) are there?

Answer 36

2

Question 37

What is the most common manifestation of HSV?

Answer 37

Cold sore

Question 38

What is a major skin manifestation of HSV infection? What may make this more serious?

Answer 38

Eczema herpticum | Can be far more severe in atopic patients

Question 39

What is the treatment for HSV?

Answer 39

Aciclovir

Question 40

What is herpes simplex virus?

Answer 40

The virus that causes chicken pox on first exposure and after that exposures result in shingles, which occurs when the virus tracks down a nerve root and affects a dermatome

Question 41

What is the causative agent in scabies? What type in infection is this?

Answer 41

Sarcoptes scabei | Infestation

Question 42

Where can scabies infection commonly centre?

Answer 42

The back, the hands, the nipples, the penis, the groin, the wrists and the toes

Question 43

What is a key sign to look for on scabies lesions?

Answer 43

Burrows

Question 44

What is the treatment for scabies infestation?

Answer 44

Permethrin cream top to toe for 8 hours - two applications two weeks apart All in household and close contact must be treated

Question 45

What is a key symptom of scabies?

Answer 45

Itching

Question 46

What is important to inform the patient with regard to the itch when starting treatment?

Answer 46

Although the cream will remove the infection the itch may take around 6 weeks to settle and can be treated symptomatically with steroids