Derm Flashcards
Naevi What do congenital naevi look like? How large can they get? What are the two main risks do they carry? When and what ix should they have?
Flat and dark in colour Giant= >20cms CNS and spine lesions Melanoma MRI brain by 6m
What is the difference between junctional, intradermal and compound naevi?
Junctional-flat
Intradermal- raises with a hair
Compound- a mix of both
Structure of the skin
What are the three main layers
Epidermis
Dermis
Subcutaneous layer
Which skin layer has further subdivisions?
What are they
Epidermis- keratinocytes
Corneum, lucidum, granulosum, spinousum, basale
Corn lovers grow straw bales
Neonatal rashes
When does erythema toxicum present
Where does it spare
If you did an investigation what would it be and what would it show?
First 24-48 hrs
Spares palms and soles
Wright staining- eosinophils
Neonatal rashes
How do transient neonatal pustular Melanosis differ to erythema toxicum
Transient- no erythema below. More common in darker skins. Neuts only in stain. Can cause hypopigmentation post
Neonates
How does cephallic pustulosis present
What is seen on smear
Like acne
Eosinophils and yeast
Neonatal rashes
What causes milaria crystallina
How do they resolve
What form has erythema
Blocked sweat glands
With cooling
Miliaria rubra
Neonatal rashes
How does acropustulosis of infency present?
What might it be secondary to?
What is seen on stain
Crops of itchy pustules usually on the hands and feet
Post scabies!
Neutrophils
Genetics and derm
What is the most common gene defect in eczema
How is it inherited?
Fillagrin
Autosomal dominant
What are the three features of nethertin syndrome
What gene is involved
What is the inheritance
Scaly dry skin (itchyosis linearis)
Atopy
Bamboo hair
SPINK 5 gene
Autosomal recessive
Hyper igE syndrome
What is the genetic defect
What is the inheritance
How does it present
Stat 3
Autosomal dominant
Eczema, coarse face, recurrent infection with encapsulated organisms, retained teeth
X linked itchiosis
What is the gene defect
What are the features
Steroid sulphatase deficient
X linked recessive
Eczema, cryptorchidism and corneal opacities
What is the difference between SJS and TEN
How do they present
What hla associations- carbamazepine, allopurinol
How soon after the drug is given does it happen
SJS<10%, ten>30%
Urti, painful skin, erythema. Blisters that slough off and crust over
Hla b 1502
Hla b 5801
7-21 days
What are the two biggest causes of erythema multiforme
What is erythema multiforme major
HSV, mycoplasma
Mucosal involvement
What is an example of a morbilliform drug eruption
EBV and amoxicillin
What does a fixed drug eruption look like
How soon after meds do they occur
Brown or purple plaque, at the same place each time
3-8 hrs
What is DRESS
How soon after drug admin does it occur
Other than stopping the drug, how can it be treated
Drug eruption with eosinophilia and systemic symptoms
More than three weeks
Steroids
What is the most common cause of serum sickness like reactions in children
Do they have immune complex deposition
Cefaclor
No! (Serum sickness LIKE)
What normally triggers urticaria multiforme
A virus
What is the key feature of the rash in hereditary angiodema
What are the most specific investigations
What is low during an attack
No wheals but angiodema
C4 level and c1 inhibitor level
C4 level
Itchyosis
What is the mildest form called
What is the lethal cause
What will a baby be born like in CIE or lamellar forms
Vulgaris
Harlequin
Colloidian body- like in a sausage
What is the risk of atopy
- 1 first degree relative has it
- 2 have it
50%
75%
What new MAB might be useful for eczema
Dupilumab- IL 4/5
Other than platelets what else can be affected by a massive haemangioma
Thyroid- hypo
Incontinenti pigmenti
What are the 4 stages
What is the gene
What are their teeth like
Vesicular verrucous hyper then hypopig
NEMO
Shark teeth!
