NEUROFIBROMATOSIS
Definition: Neurofibromatosis (NF) is a genetic condition that affects the nervous system, muscles, bones and skin. There are two major forms: both forms of NF are characterised by the growth of benign tumours called neurofibromas. These tumours can grow anywhere in the body where there are nerve cells–this includes nerves just under the surface of the skin, as well as nerves deeper within the body, spinal cord, and/or brain.

The two types of NF are:
1. Neurofibromatosis Type I: also known as Von Recklinghausen
disease, it is due to mutation on chromosome 17q11.2, the gene product being neurofibromin (a GTPase activating enzyme). In NF1, neurofibromas most commonly grow on the skin or on the nerve to the eye.
2. Neurofibromatosis Type II: also known as MISME Syndrome, it is due to mutation on chromosome 22q, the gene responsible for producing merlin, a cytoskeletal protein. In NF2, neurofibromas most commonly grow within the spinal cord or brain. Specifically, the
tumours are found on the nerves to the ear, called acoustic neuromas, or the nerves for balance, called vestibular schwannomas.

Aetiology/Risk Factors:
NF is caused by a change in our genetic material. These mutations can be caused by                                                                                       * Autosomal Dominant Inheritance: if either parent has NF, there is a 50% chance with each pregnancy that the gene causing NF will be passed on to the child.
* Spontaneous Occurrence: in approximately 50% of cases, NF occurs in an individual who has no family history of the disorder. This happens when there is a spontaneous change in the genetic material carried by either the sperm or the egg.

Common signs and symptoms of NF1 include:
* multiple neurofibromas on the skin and under the skin
* various other skin phenomena such as freckling of the groin and the arm pit
* the presence of 6 or more Café-aulait spots (pigmented birthmarks)
* skeletal abnormalities such as scoliosis or bowing of the legs
* lisch nodules
* tumour on the optic nerve
* plexiform neurofibroma
* learning disabilities

Common signs and symptoms of NF2 include:
* Bilateral tumours, acoustic neuromas on the vestibulocochlear nerve
* hearing loss due to acoustic neuromas
* the tumours may cause headaches, balance problems, vertigo
* facial weakness/paralysis
* deafness and tinnitus
* learning disabilities