paeds derm

Question 1

what is stevens johnson syndrome

Answer 1

a severe systemic reaction affecting the skin and mucosa that is almost always caused by drug reactions

Defined as severe skin detachment with mucocutaneous complications

Question 2

Aetiology of stevens johnson syndrome

Answer 2

infection: URTI, pharyngitis, otitis media, herpes

Vaccinations: small pox

Medications:
- anticonvulsants
- antibiotics
- antifungals
- NSAIDs
- penicillin
- allopurinol
- oral contraceptive pill
- sulphonamides

Question 3

patients with what disease are at an increased risk of SJS

Answer 3

patients with HIV and active cancer

Question 4

pathophysiology of stevens johnson syndrome

Answer 4

immune reaction to foreign antigens- immune complex mediated

Question 5

what can stevens johnson develop into ?

Answer 5

toxic epidermal necrolysis

Question 6

How does stevens johnson syndrome present?

Answer 6

rash- maculopapular with target lesions, can develop into vesicles and bullae

Nikolsky’s sign- the epidermal layer sloughs easily off when pressure is applied

erosions and ulcerations of eyes, lips, mouth, pharynx, oesophagus, GI tract

Systemic symptoms- fever, arthralgia

Question 7

differentials for stevens johnsons syndrome

Answer 7

staphyloccocal scalded skin
toxic shock syndrome
erythema multiforme
burns

Question 8

What is the definitive test for stevens johnsons syndrome

Answer 8

skin biopsy - shows keratinocyte apoptosis with detachment of the epidermal layer of the skin from the dermal layer

Question 9

1st line management of stevens johnsons syndrome

Answer 9

hospital admission and removal of the causative agent

Question 10

treatment of stevens johnson syndrome

Answer 10

• hospital admission and removal of the causative agent
• VTE prophylaxis
• surgical wound care
• analgesia
• fluid and electrolyte management
• nutritional support
• PPI

May consider IV immunoglobulins

Question 11

what percent of the skin is involved in stevens johnson syndrome

Answer 11

less than 10%

Question 12

what percent of the skin is involved in toxic epidermal necrolitis

Answer 12

at least 30%

Question 13

mortality rate of stevens johnsons syndrome

Answer 13

10%

Question 14

what can cause mortality in stevens johnsons syndrome (3)

Answer 14

dehydration
infection
disseminated intravascular coagulation

Question 15

What are strawberry naevi and when do they present?

Answer 15

a type of birth mark, also called cavernous haemangioma
They present a few weeks after birth and usually regress over few years

Question 16

How can strawberry naevi be treated?

Answer 16

topical propranolol- if severe and affecting vision or airways may use oral propranolol

Question 17

What is a mongolian blue spot

Answer 17

a blue/black discolouration at the base of the spine and buttocks - it is a type of birth mark that usually fades over the first few years and can be commonly mistaken for bruises

Question 18

What is a port-wine stains

Answer 18

a birth mark present from birth that is due to vascular malformation of the capillareis in the dermis

Question 19

associations of port wine stains

Answer 19

if along the trigeminal nerve they may be associated with intracranial vascular abnormalities (Sturge -weber syndrome) or severe lesions on the limbs with bone hypertrophy (Klippel trenuay sydnrome

Question 20

what may be used to reduce the appearance of port wine stains

Answer 20

lase therapy

Question 21

Causes of eczema exacerbations (6)

Answer 21

bacterial or viral infections
ingestion of irritants
contact with irritants or allergens
environmental factors - heat, humidity,
change in medication
psychological stress

Question 22

Describe eczema

Answer 22

itchy erythematous rash
in infants it commonly affects the face and scalp
in older children it is common in the skin flexures and frictional areas (neck, wrists)

Question 23

How is eczema managed

Answer 23

• avoidance of irritants
• emollients
• topical steroids
• wet wrapping

Question 24

Give some examples of mild, moderate and potent steroids

Answer 24

mild- 1% hydrocortisone
moderate- clobetasone butyrate (0.5%)
potent- betamethasone valerate (0.1%)

Question 25

what types of medicaations might be used in very severe eczema

Answer 25

oral steroids
immunmodulators- calcineurin inhibitors
light therapy
DMARDS and biologics

Question 26

What can occur if someone with eczema gets infected with HSV

Answer 26

eczema herpeticum

Question 27

How does eczema herpeticum present ?

Answer 27

vesicles and punched out erosions appear at many sites on the body

Question 28

how is eczema herpeticum diagnosed?

Answer 28

swab and Tzanck test

Question 29

How is eczema herpeticum treated

Answer 29

IV aciclovir (often given with antibiotics as hard to differentiate)

Question 30

what is allergic rhinitis

Answer 30

inflammation of the internal nose caused by an allergen

Question 31

What type of reaction is allergic rhinitis

Answer 31

type 1 hypersensitivity (IgE mediated)

Question 32

What three subtypes of allergic rhinitis are there?

Answer 32

seasonal (hayfever)
perennial
occupation

Question 33

How does allergic rhinitis present?

Answer 33

sneezing
bilateral nasal obstruction
clear nasal discharge
post nasal drip
nasal pruritis
itchy swollen eyes

Question 34

How is allergic rhinitis treated?

Answer 34

avoidance of the allergen

mild- intranasal or oral antihistamines

moderate - severe- intranasal corticosteroids

Question 35

What should be avoided in chronic allergic rhinitis

Answer 35

topical nasal decongestants - can cause rebound hypertrophy of the nasal mucosa on withdrawal
(rhinitis medicamentosa)

Question 36

How does eczema locations differ with age?

Answer 36

infants- face and trunk
young children- extensor surfaces
older children- flexor surfaces, neck