Drug-induced Rashes

Question 1

What is a porphyrin?

Answer 1

Photosensitive pigment

Question 2

Pseudoporphyria presentation

Answer 2

Bulbous rash on hands and feet
Photosensitive
Heals with scars and milia
Porphyrin studies negative (histologically different from porphyria)

Question 3

Drug-induced rash management

Answer 3

Stop drug
Antihistamine
Steroids (oral/topical)

Question 4

Erythema multiforme presentation

Answer 4

Target papules and plaques
Normally starts acral distribution (hands, feet, head)
Mild mucosal involvement
Systemic symptoms absent or mild tend to reoccur

Question 5

What is Stevens-Johnson syndrome on a spectrum with?

Answer 5

Toxic epidermal necropsy is (TEN)

Question 6

Describe SJS skin presentation

Answer 6

Macules or blisters developing into sheets of skin detachment

Question 7

What is Nikolsky sign?

Answer 7

Top layers of skin slip away from lower layers when rubbed

Question 8

What scoring system is used in SJS?

Answer 8

SCORTEN

Question 9

Describe a fixed drug eruption

Answer 9

Solitary erythematous plaque, bullae or erosion
Occurs 30mins-8hours
Resolves in few weeks
Hyperpigmented after

Question 10

What is DRESS?

Answer 10

Drug hypersensitivity syndrome
Drug rash +eosinophilia+ systemic symptoms

Question 11

DRESS syndrome symptoms

Answer 11

Patient unwell
Can have hepatosplenomegaly
Fever
Papules, facial oedema, exfoliating dermatitis
Lymphadenopathy
Name: eosinophilia, atypical lymphocytes
Organ involvement: hepatitis, carditis, interstitial nephritis, interstitial pneumonitis

Question 12

Drug-induced pigmentation - amiodarone

Answer 12

Slate grey

Question 13

Drug-induced pigmentation - antimalarial (>4 months)

Answer 13

Brown or blue-black

Question 14

Drug-induced pigmentation - oestrogen/progesterone

Answer 14

Hyperpigmented patches eg. Melasma