What are Neurocutaneous diseases?

Cutaneous manifestations that are characteristic of certain neurological disease are described here

Tuberous sclerosis  is characterised by the following lesions

• Adenoma sebaceum/Angiofibroma of face 
• Subungual  fibroma
• Shagreen patch
• Leafy macule

Von Recklinghausen's disease

• Multiple cutaneous and subcutaneous neurofibroma
• Cafe-au-lait spots > 6 in no: >1.5 cm in size
• Axillary freckles

Sturge Weber syndrome

Capillary hemangioma in trigeminal nerve distribution is seen in Encephalo-trigeminal angiomatosis

Hereditary hemorrhagic telangiectasia

There is multiple telangiectasia of skin, mucosa, and pulmonary system

What is Cafe au lait spot?

Cafe au lait spots are macule that are seen in more than 90 percentage of people with Neurofibromatosis Type 1 and 2

• They appear as light brown round to ovoid macules with smooth borders often located over the nerve trunk with their long axis parallel to the cutaneous nerves
• It is significant when the number is more than 6 and each more than 1.5 cm in diameter 

Cafe au lait macules are also seen in McCune-Albright syndrome.
They differ from neurofibromatosis in the following

• They have irregular borders 
• They are seen in the midline