Neurofibromatosis is caused due to defects in which pathway?
Ras-GAP
What does the Ras-GAP pathway lead to?
Production of transcription factors and cell growth
How can neurofibromatosis be treated?
MEK inhibitors
(slows down Ras-GAP pathway)
Similar treatment for melanomas
Cafe au lait macules are associated with which condition?
Neurofibromatosis
Infantile seizures are associated with which genetic condition that also has skin manifestations?
Tuberous sclerosis
How does tuberous sclerosis affect the bones?
Causes development of bone cysts
What is a hamartoma?
Overgrowth of normal tissue within body organs that is benign
Also known as angiomyolipoma
Hamartomas are associated with which condition?
Tuberous sclerosis
What is the name given to the key group of inherited blistering skin disorders?
Epidermis bullosa
By which terms can staphylococcal scaled skin syndrome be referred to in infants?
Ritter's disease of the newborn
Pemphigus neonatorum
Staphylococcal scaled skin syndrome does affect the mucous membranes
True or false?
False
It is epidermolysis conditions which affect the mucous membranes
What are the different types of epidermolysis bullosa?
- EB Simplex (epidermal involvement)
- Junctional EB (DEJ involvement)
- Dystrophic EB (dermis involvement)
What is the term given to a type of epidermolysis bullosa that is autoimmune?
Epidermolysis bullosa aquisita
In terms of producing protein, which mutation type will result in no protein production?
Autosomal recessive
Which signs and symptoms are associated with tuberous sclerosis?
- Infantile seizures
- Facial angiofibromas
- Periungual fibromas
- Longitudinal rail ridging
- Ash-leaf macule
- Shagreen patches
- Enamel pitting
- Learning difficulties and slow development
What are facial angiofibromas?
Small pink/red macules districutes in a butterfly pattern across the face
Atopic eczema has ____ penetrance
Atopic eczema has low penetrance
Which area in the skin does epidermolysis aquista affect?
DEJ
Which clinical sign is generally the first clinical sign to develop for tuberous sclerosis?
Ash-leaf macule
(a depigmented lesion)
How mnay cafe-au-lait macules are required to suggest a genetic disease?
>5
Suggest neurofibromatosis
When do cafe-au-lait macules generally appear?
Within first 3 years of life
What are Shagreen patches?
Flesh coloured orange-peel connective tissue naevi of varying sizes, usually on the lower back
Ichthosis vulgaris is associated with a mutation in which gene?
Filaggrin
What is ichthosis vulgaris?
The skin loses its ability to shed normally so dry dead skin patches accumulate on the skin surface giving the appearance of fish scales
What causes tuberous sclerosis?
Either of two gene mutations:
- TSC1
- TSC2
Mutations in the filaggrin gene can be associated with which conditions?
- Asthma
- Eczema
- Peanut allergy
Filaggrin mutations are often associated with allergy
Tuberous sclerosis has what level of penetrance?
High
Neurofibromatosis is associated with which clinical signs?
- Cafe-au-lait macules
- Neurofibromas
- Plexiform neuroma (diffuse)
- Axillary or inguinal freckling
- Optic glioma
- 2 or more Lisch nodules
- Distinctive bony lesion
What are Lisch nodules?
Iris hamartomas
