Miscellaneous genetic diseases
- Recognise cutaneous signs of neurofibromatosis, tuberous sclerosis and pseudoxanthoma elasticum.
Cutaneous signs of type 1 neurofibromatosis include:
- Café au lait macules
- Skin tags
- Axillary freckling
Café au lait macule
Tuberous sclerosis, also known as epiloia, is an autosomal dominant genetic neurodermatosis that presents with epilepsy, mental retardation and cutaneous signs. These include:
- Angiofibromas (firm pink papules on nose and cheeks
- Ash-leaf hypopigmented macules
- Periungual fibromas (warty nodules around nails)
- Connective tissue hamartomas (skin-coloured firm plaques)
Pseudoxanthoma elasticum (PXE) is a group of inherited disorders in which elastic tissue in skin, blood vessels and eyes is defective. The result is groups of yellowish bumps on the neck, axillae and elsewhere associated with gastrointestinal haemorrhage, hypertension, peripheral vascular disease and ocular “angioid” streaks and retinal haemorrhages.