Derm

Question 1

Dx this rash?

Answer 1

Pityriasis Alba
- 1 to 20 patches or thin plaques.
- Most on face- cheeks and chin.
- Round, oval or irregular shape.
- Minimal itch

Question 2

Dx this rash?

Answer 2

Pityriasis versicolour
- Fungal rash
- Rx: Selsun

Question 3

Dx this rash?

Answer 3

Vitiligo
Acquired depigmenting disorder- loss of melanocytes - Well-defined patches, confetti like
Small patches or macules are sometimes described as confetti-like.
Vitiligo also favours sites of injury (cuts, scrapes, acne, thermal burns and sunburn). This is called the Koebner phenomenon.

Question 4

Dx this rash?

Answer 4

Vitiligo
Acquired depigmenting disorder- loss of melanocytes - Well-defined patches, confetti like
- Koebner phenomenon: favours sites of injury

Question 5

Dx this rash?

Answer 5

Tinea corporis
- Itchy
- Inflamed & erythematous
- +/- pustular

Question 6

Diagnosis & management?

Answer 6

Haemangioma
Increases in size and resolves first year of life
1. Uncomplicated/localised- active monitoring/topical therapies (BB- superficial with cosmetic concern, steroids - small/deep)

2. High risk/complicated (large, segmental, facial risking disfigurement/scarring) = propanolol (Cx= shock, bradycardia, asthma, prem)
   - Steroids second line
   - Vincristine/IFNa (inhibits angiogenesis)

Question 7

PHACE syndrome- features

Answer 7

Posterior fossa brain malformations
Haemangiomas, particularly large, segmental facial lesions
Arterial anomalies
Cardiac (heart) anomalies and coarctation of the aorta/septal defects
Eye abnormalities and Endocrine abnormalities

Question 8

Dx & patho?

Answer 8

Milia
- Keratin containing cysts
- 50% of babies
- Spont res

Question 9

Dx & patho?

Answer 9

Erythema toxicum
- Erythematous macules with papules- contain eosinophils
- Can evolve into staph infection

Question 10

How many mites are initially present in scabies infection?

Answer 10

10-15

Question 11

Features of SJS/TENs

Answer 11

Cytotoxic T-cells (CD8+) attack epithelial cells in mucosa and epidermis, release perforin/granzymes, IFN-y/TNF-a = cell death, dehydration, infection

Exudative erosions of lips, oral mucosa, eyes, genital mucosa; targetoid papulovesicles of skin, skin sloughing, and skin pain

Histo: vacuolar interface dermatitis or epidermal necrosis

Drugs:
- Bactrim
- CBZ, phenytoin
- NSAIDS (meloxicam)
- Allopurinol

Can occur days-months after drug exposure

Question 12

Features of DRESS

Question 13

Features of staph scalded skin syndrome

Answer 13

Toxin mediated rash caused by staph

Cleavage of desmoglein 1 (anchor keratinocytes to one another)

• Blisters in areas of stress
• Pressure = seperation of epidermis (Nikolskys sign)

Add clindamycin

Question 14

Features of EB

Answer 14

Skin fragility and blister formation from minor trauma

EB simplex
- keratin, intraepiderma
Junctional EB
- laminar, laminin mutations
Dystrophic EB
- subepidermal
- collagen mutations
Kindler syndrome

Question 15

Features of incontinentia pigmenti

Answer 15

X-linked dominant (lethal to males)

IKBKG/NEMO

Staged cutaneous eruption

Variable developmental abnormalities involving the teeth, hair, and nails

Ocular and neurologic abnormalities

Question 16

Difference between bullous pemphigoid and pemphigus?

Answer 16

Bullous pemphigoid
- subepidermal blisters
- flexural
- IF = IgG and C3 on basement membrane

Pemphigus vulgaris
- Abs to desmoglein3
- Nikolsky positive
- Needs systemic immunosuppression