Tuberous Sclerosis Flashcards
What is tuberous sclerosis?
Tuberous sclerosis is a genetic condition that causes features in multiple systems.
The characteristic feature is the development of hamartomas: benign neoplastic growths of the tissue that they origin from.
Genetics
Tuberous sclerosis is caused by mutations in one of two genes:
- TSC1 gene on chromosome 9, which codes for hamartin
- TSC2 gene on chromosome 16, which codes for tuberin
Hamartin and tuberin interact with each other to control the size and growth of cells.
Skin Clinical Features
Ash leaf spots are depigmented areas of skin shaped like an ash leaf
Shagreen patches are thickened, dimpled, pigmented patches of skin
Angiofibromas are small skin coloured or pigmented papules that occur over the nose and cheeks
Subungual fibromata are fibromas growing from the nail bed. They are usually circular painless lumps that grow slowly and displace the nail
Cafe-au-lait spots are light brown “coffee and milk” coloured flat pigmented lesions on the skin
Poliosis is an isolated patch of white hair on the head, eyebrows, eyelashes or beard
Neurological Features
Epilepsy
Learning disability and developmental delay
Features in the rest of the body
Rhabdomyomas in the heart
Gliomas (tumours of the brain and spinal cord)
Polycystic kidneys
Lymphangioleimyomatosis (abnormal growth in smooth muscle cells, often affecting the lungs)
Retinal hamartomas
Management
Management is supportive with monitoring and treating complications such as epilepsy.
There is no treatment for the underlying gene defect.
