NEUROFIBROMATOSIS

Neurofibromatosis, also known as von Recklinghausen's disease, and is a hereditary (genetic) disorder of overgrowth and abnormal growth of embryonic neural components within the body.

Appearance of Skin and Signs of Neurofibromatosis

The patient presents with light-dark brown patches called cafe-au-lait spots. These spots are usually greater than 1.5 cm in adults and there should be more than 6 of them. In children, less than 5, these patches are smaller, greater than 0.5 cm and more than 5 are usually present.

 

Epidemiology and Causes of Neurofibromatosis

The neurofibromatoses are genetic disorders of the nervous system that primarily affect the development and growth of neural/nerve cell tissues. These disorders cause tumors to grow on nerves. In addition, neurofibromatoses produce numerous skin changes, as well as bone deformities. These signs are essential, as they can help aid in the diagnosis of a patient with neurofibromatoses early on. These diseases are found in about 0.3% of the population. These diseases are a genetic disease - mainly inherited from your parents. However, even though many affected persons inherit the disorder, between 30 and 50 percent of new cases arise spontaneously through a mutational event, which changes a persons genetic material, and affects their genes. Genes subsequently turn into proteins that are the active components in the body and may cause disease if formed abnormally. Once this change has taken place, the mutant gene can be passed on to the patients children, as the mutation has affected the patients germ cells. This occurs because this disease usually presents when a person is born, and therefore, the mutation has propagated throught the cells of their body, including their germ cells, which form either spermatocytes in a male or ova (eggs) in a female.

Because neurofibromatoses are numerous, scientists have classified the disorders as neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2). NF1 is the more common type of the neurofibromatoses. In diagnosing NF1, a physician looks for changes in skin appearance, tumors, or bone abnormalities, and/or a parent, sibling, or child with NF1. Symptoms of NF1, particularly those on the skin, are often seen at birth or during infancy. The latest that skin changes are seen, is almost always by the time a child is about 10 years old. NF2 is less common. NF2 is characterized by tumors of the eighth cranial nerve on both sides of the body. Cranial nerve eight is essential for hearing, it is the acoustic nerve that goes to the ear and allows for hearing. In addition, it is the nerve that allows for the vestibular functions of the body, such as balance and position senses.

It therefore has severe consequences, if this nerve is affected. These tumors can also cause pressure that can damage neighboring nerves, including other cranial nerves, such as the ones that can cause tongue sensation and motor/muscle contractions to the face. To determine whether an individual has NF2, a physician will inspect the paitnet and do a head and neck exam, especially looking for bilateral eighth nerve tumors, which can be done through a CT scan or through a clinical examination with tunning forks, numerous manouverse to test balance and gait and hearing tests. Similar signs and symptoms in a parent, sibling, or child are of great concern and should always be presented to a physician. Affected individuals may notice hearing loss as early as the teen years. Other early symptoms may include tinnitus (ringing noise in the ear) and poor balance. Headache, facial pain, or facial numbness, caused by pressure from the tumors, may also occur. Neurofibromatosis is also associated with many other diseases, such as hypertension from renal artety stenosis, scoliosis of the back, bone cysts and developmental delay. MOST IMPORTANTLY, these disorders are associated with a high malignant potential, and can lead to astrocytoma, acoustic neuroma, neurofibrosarcoma. It is therefore essential that these paitens be followed very closely by a physician or numerous specialists.

Neurofibromatosis Treatments

Treatments for both NF1 and NF2 are presently aimed at controlling symptoms. Complete cure rates are not possible, as these are inherited genetic diseases, and affect every cell of an individual. Gene therapy may hold promise in the future, however, current trials have not produced the results that were much expected. To alleviate symptoms, surgery can help some NF1 bone malformations and remove painful or disfiguring tumors; however, there is a chance that the tumors may grow back and in greater numbers.