Skin disorders

Question 1

How is the skin in a preterm infant different to a term birth?

Answer 1

The skin is thin, poorly keratinised and lacks subcutaneous fat

Question 2

How is water loss different in preterm infants to term infants?

Answer 2

Transepidermal water loss is markedly increased and they are unable to sweat

Question 3

What are congenital pigmented naevi?

Answer 3

Moles involving extensive areas of the skin.
Rare but disfiguring
4-6% lifetime risk of malignant melanoma
Prompt referral to paeds derm and plastics to assess removal

Question 4

What are the risk factors for malignant melanoma?

Answer 4

Positive FHx
Large number of moles
Fair skin
Repeated episodes of sunburn
Living in a hot climate

Question 5

What is albinism?

Answer 5

A defect in biosynthesis and distribution of melanin.

Question 6

How does the lack of pigment in the iris, retina, eyelids and eyebrows in albinism affect function?

Answer 6

Failure to develop fixation reflex.
Pendular nystagmus
Photophobia.
The disorder is an important cause of visual impairment

Question 7

What is eczema?

Answer 7

A genetic deficiency of skin barrier function.

Question 8

What age does atopic eczema often present?

Answer 8

Usually in the first year of life, but uncommon in the first two months. Exclusive breast-feeding may delay the onset.

Question 9

When does atopic eczema usually resolve by?

Answer 9

Mainly a disease of childhood.
50% resolved aged 12
75% resolved aged 16

Question 10

How does eczema often present?

Answer 10

Itching, scratching and exacerbation of the rash.
The excoriated areas become erythematous, weeping and crusted.
Atopic skin is usually dry, and prolonged scratching and rubbing may lead to lichenification (accentuation of the normal skin markings)

Question 11

What are some causes of exacerbations of eczema?

Answer 11

Bacterial infection
Viral infection
Ingestion of an allergen
Contact with an irritant or allergen
Environment: heat, humidity
Change or reduction in medication
Psychological stress
Unexplained

Question 12

What is a complication of eczema?

Answer 12

Infection

Question 13

How would you treat eczema?

Answer 13

Avoiding irritants and precipitants
Emollients
Topical corticosteroids (hydrocortisone)
Immunomodulators (tacrolimus)
Occlusive bandages (prevent itching, especially at night)
Antibiotics or antivirals if infected
Dietary elimination 
Psychosocial support

Question 14

How would you treat viral warts?

Answer 14

Daily application of proprietary salicylic acid and lactic acid paint or glutaraldehyde.
Cryotherapy with liquid nitrogen

Question 15

What is ringworm?

Answer 15

Dermatophyte funghi invade dead keratinous structures, such as the horny layer of skin, nails and hair

Question 16

How do you diagnose ringworm?

Answer 16

Fungal hyphae on skin scrapings

Question 17

How do you treat ringworm?

Answer 17

Antifungals

Question 18

What are the symptoms of scabies?

Answer 18

Very itchy burrows, papule an vesicles - distribution varies with age.
Scratching leads to excoriation, secondary eczematous or urticarial reaction often with secondary infection.

Question 19

How do you treat scabies?

Answer 19

Permethrin cream should be used by the whole family

Question 20

When does psoriasis normal present?

Answer 20

Not before 2 years

Question 21

What type of psoriasis is common in children and what does it often preceded by?

Answer 21

Guttate type is most common.

Preceded by strep or viral sore throat or ear infection.

Question 22

How does psoriasis normally present and for how long?

Answer 22

Lesions are small, raindrop like, round or oval erythematous scaly patches on the trunk and upper limbs.
An attack usually resolves over 3-4 months.

Question 23

Does psoriasis in children normally recur?

Answer 23

Yes, most get a recurrence within the next 3-5 years

Question 24

How do you treat psoriasis?

Answer 24

Guttate - bland ointments

Question 25

What is the cause of acne?

Answer 25

Androgenic stimulation of the sebaceous glands and an increased sebum excretion rate. Obstruction to the flow of sebum in the sebaceous follicle initiates the process of acne

Question 26

How does acne present and at what age?

Answer 26

1-2 years before puberty.
A variety of lesions, initially open comedones (blackheads) or closed comedones (whiteheads) progressing to papule, pustules, nodules and cysts.

Question 27

Where does acne usually present?

Answer 27

Lesions occur mainly on the face, back, chest and shoulders

Question 28

How do you treat acne?

Answer 28

Topical keratolytic agent, benzyl peroxide

Sunshine, in moderation, topical antibiotics or topical retinoids may be helpful.