Y5 - Drug reactions (incl. Stevens-Johnson syndrome, toxic epidermal necrolysis spectrum)

Question 1

def of SJS

Answer 1

severe skin detachment with mucocutaneous complications

Question 2

what is SJS a more severe version of

Answer 2

erythema multiforme major

Question 3

what is SJS a less severe version of

Answer 3

toxic epidermal necrolysis (TEN)

Question 4

how is SJS and TEN differentiated

Answer 4

SJS <10% total body surface area

TEN <30% total body surface area

Question 5

what is Nikolskys sign?

Answer 5

when the epidermal layer easily sloughs off when pressure is applied

Question 6

epi

Answer 6

TEN rare than SJS

Question 7

aetiology

Answer 7

1 infection
2 vaccination
3 medicine

Question 8

what infections cause SJS

Answer 8

URTIs
Pharyngitis
Herpes
EBV
Mycoplasma pneumoniae

Question 9

what vaccinations cause SJS

Answer 9

smallpox vaccination

Question 10

what medicines cause SJS

Answer 10

anticonvulsants
antibiotics
antifungals
corticosteroids

Question 11

pathophysiology

Answer 11

detachment of epidermis from the papillary dermis at the epidermal-dermal junction

Question 12

signs and symptoms

Answer 12

RFs
sudden rash which develops after a new medicine
mucosal involvement
-erosions or ulceration of eyes. lips, mouth, eye, genital area
nikolskys sign

Question 13

who is mucosal involvement more common in

Answer 13

SJS patients

Question 14

RFs

Answer 14

anticonvulsants (carbamazepine, phenobarbital, phenytoin)
recent infection (mycoplasma pneumoniae)
recent antibiotic use
SLE

Question 15

what is the definitive test for diagnosis

Answer 15

skin biopsy

Question 16

what would you find on skin biopsy

Answer 16

keratinocyte apoptosis with detachment of the epidermal layer of the skin from the dermal layer

Question 17

how would you rule out toxic shock syndrome

Answer 17

with blood cultures positive for staph or strep

negative in SJS/TEN

Question 18

what would eosinophilia on FBC suggest

Answer 18

hypersensitivity syndrome

Question 19

management

Answer 19

1 urgent evaluation and withdrawal of causative agent
2 dressings, topical antibacterials, emollients
-bacitracin topical
-silver sulfadiazine
3 opthalmological examination
4 IV fluids and nutritional support

Question 20

complications

Answer 20

dehydration is common
compartment syndrome
abnormal skin pigmentation

Question 21

prognosis

Answer 21

prognosis is best when:

• patient <50yrs
• total body surface area is low
• patients are transferred to a burn centre
• no sepsis
• do not require anitbiotics

Question 22

what is the mortality in SJS

Answer 22

1-5%

Question 23

what is the mortality in TEN

Answer 23

25-35%