Paediatric dermatology

Question 1

Red/pink patch seen in up to 50% babies, often on face/nuchal folds

Answer 1

Salmon patches

Question 2

What is the main difference between a vascular malformation and a haemangioma in a child?

Answer 2

Vascular malformations do not resolve and may even progress; haemangiomas usually regress

Question 3

Pink-purple macules appearing usually on the face and trunk; do not regress spontaneously and can be grossly disfiguring

Answer 3

Port-wine stains

Question 4

What causes port-wine stains?

Answer 4

Dilated dermal capillaries

Question 5

What is Sturge-Weber syndrome?

Answer 5

Syndrome of vascular malformation of the leptomeninges, which can cause:
epilepsy
low IQ
hemiparesis
Glaucoma
associated with port-wine stain of the trigeminal area

Question 6

What is the name of the syndrome where port-wine stain is associated with progressive limb overgrowth?

Answer 6

Klippel-Trenauney

Question 7

Factors which predispose to strawberry naevi? (4)

Answer 7

Girls
Preterm infants with LBW
Multiple gestation
Older mothers

Question 8

What is a sign of spontaneous regression of a strawberry naevus?

Answer 8

Central whitening

Question 9

What proportion of strawberry naevi have regressed by age 5?

Answer 9

50%

Question 10

Management of strawberry naevus

Answer 10

Observation and management, unless complicated

Question 11

Complications of strawberry naevi (3)

Answer 11

Opthalmic involvement requires specialist input to prevent astigmatism/ambylopia
Lesions may ulcerate, bleed profusely
Interference with feeding, swallowing

Question 12

Management of complicated strawberry naevi (3)

Answer 12

Propanolol
Pulsed dye lasers (large)
Plastic surgery (failure to regress)

Question 13

Cafe au lait macules are signs of which genodermatosis?

Answer 13

Neurofibromatosis (NF 1)

Question 14

What are Lisch nodules?

Answer 14

Aggregates of melanocytes affecting the iris, seen in NF1

Question 15

Which chromosome carries the gene which is defective in NF1, and what is the inheritance pattern?

Answer 15

chr 17. Autosomal dominant with variable penetrance

Question 16

Skin features of tuberous sclerosis?

Answer 16

Depigmented ash-leaf macules in 90%
Cafe au lait macules
Periungal fibroma
Adenoma sebaceum
Shagreen patches

Question 17

What are shagreen patches?

Answer 17

Areas of thick, dimpled skin

Question 18

Tuberous sclerosis genes?

Answer 18

chr 9 and chr 16