Neurofibromatosis is a hereditary disease that manifests in two forms, type 1 and type 2. Type 2, in which the affected person suffers from benign tumors in the brain and the symptoms they cause – hearing problems, paralysis of the facial nerves, and balance disorders – is comparatively rare. Neurofibromatosis is not curable, but it can be treated well enough to prevent possible complications.
What is neurofibromatosis type 2?
Neurofibromatosis type 2, like the more common type 1, is considered a congenital and inherited disorder. In fact, however, it has been found that circa 50% of those with the disease have a new mutation, meaning that there are no cases of the disease within the family. The main feature of the disease is benign brain tumors that develop on both sides of the auditory and vestibular nerves and cause specific symptoms. The typical symptoms of neurofibromatosis type 2 are reduction or loss of hearing, tinnitus, balance disorders, paralysis of the facial muscles and premature cataracts. This form of the disease is much less common than neurofibromatosis type 1, also known as Recklinghausen’s disease. The incidence is 1:35000, whereas that of type 1 must be seen at 1:3500.
Causes
The cause of each form of neurofibromatosis is mutations in the corresponding neurofibromatosis gene on chromosome 22. This gene is thought to affect the migratory behavior and shape of certain cell types, so that a defect is highly likely to lead to tumor disease. About half of the new cases are based on spontaneous gene mutations and are not hereditary. Nevertheless, neurofibromatosis is considered to be a hereditary disease. As such, the disease is inherited in an autosomal dominant manner, which, in simplified terms, means that inheritance is independent of sex, but definitely if one parent is affected.
Symptoms, complaints, and signs
Patients with neurofibromatosis type 2 develop tumors in the brain and spinal cord. Pigmentary changes as in NF type 1 are possible in reduced incidence. Characteristic of type 2 are tumors on nerves in the body. These arise from the protective layer of nerve cells, the Schwann cells. Main infestation is in the area of the brain, auditory nerves and in the spine. Depending on the tumor size and its localization, different symptoms occur. These include perception of disturbing sounds and a general decline in hearing ability. Patients cannot reliably maintain their balance, facial muscles are occasionally affected by paralysis ]] with a tendency to vomit, orientation problems and headaches. The spread to the auditory nerves is usually symmetrical. Medicine refers to this characteristic as bilateral acoustic neuroma. In most cases, this progression is not apparent until after puberty. A permanent ringing or whistling (tinnitus) accompanies the balance problems. Changes in the eyes also indicate neurofibromatosis type 2. A clouding of the eye lens (juvenile cataract)makes visual perception of patients difficult and is one of the early identifying features of central neurofibromatosis. In addition, isolated tumors appear on the skin as in NF type 1, but the typical Lisch nodule is absent in the eye area. Long-term symptoms include severe hearing impairment to deafness, manifestation of facial paralysis, difficulty swallowing, and voice impairment due to functional dysfunction of the vocal cords.
Diagnosis and course
The symptoms of neurofibromatosis type 2 are nonspecific, so the correct diagnosis is difficult and can be lengthy. If symptoms and risks are present that may indicate the presence of the disease, especially hearing loss and balance problems, a thorough examination must be performed. First, blood is taken in order to perform a DNA analysis. Blood analysis is already possible in the course of prenatal diagnostics. Since the main feature of neurofibromatosis type 2 is bilateral benign tumors of the auditory and vestibular nerves, an imaging procedure must then be initiated. Only if the tumors are detectable in this, the disease may be diagnosed. Further clear criteria are the disease of one or both parents and the detection of tumors and fibromas.If neurofibromatosis type 2 has been diagnosed, the extent of the disease must be determined by means of EEG, hearing test, imaging examination of the spine and a psychological examination in order to be able to initiate optimal care for the patient. Two courses of neurofibromatosis are distinguished: the initial onset before the age of 20 with rapid tumor progression, the Wishart phenotype, and the slow disease progression after the age of 20. The latter is known as the Feiling-Gardner phenotype.
Complications
Although neurofibromatosis type 2 is a rare, hereditary disease, it is more likely to lead to various complications depending on the location of the tumors. In general, the number of tumors, albeit benign, increases during the course of the disease. Since these are mainly located in the brain or the spinal cord, they can lead to neurological deficits in the long term. However, the complications usually do not occur until adulthood and can often be prevented by surgical removal of the tumors. One of the most common complications is the dysfunction of the eighth cranial nerve, which is responsible for hearing and the sense of balance. This can lead to hearing loss or even deafness. Furthermore, dizziness is common. Other frequent complications are facial nerve paralysis, vocal cord paralysis or dysphagia. In addition, coordination disorders of movement (ataxia), gait disorders and headaches may occur. If the spinal cord is affected, even paraplegia occurs in extreme cases. Ocular changes are also frequently observed, which can lead to a cataract (clouding of the lens) already in adolescence. The most severe complications can be avoided by surgical removal of the tumors. However, since recurrences often develop, even surgery cannot always prevent the occurrence of complications. Furthermore, the risk of benign tumors transforming into malignant tumors is significantly increased compared with the general population.
When should you see a doctor?
A general feeling of illness, malaise, or limitations in various functional abilities should be clarified by a physician. If there are noticeable weight fluctuations, problems with orientation or paralysis, a doctor is needed. Changes in skin appearance, pain or limitations in hearing should be examined and treated. Perception of sounds that go unheard by fellow humans is just as worrisome as deafness. If there are disturbances in balance, an increase in minor accidents or falls, and unsteadiness in gait are complaints, a visit to the doctor should be made. A clouding of the cornea, optical changes in the area of the eyes,as well as changes in vision are further signs of a disease. Complaints when swallowing or a feeling of tightness in the throat should be examined by a doctor. Changes in the voice, restrictions in phonation or a refusal to eat are indications of a health irregularity, a visit to the doctor is necessary. If the existing complaints increase as the disease progresses, a doctor is needed. If anxiety or behavioral abnormalities develop, the affected person should seek help. If mood swings, a loss of well-being or quality of life occur, a doctor’s visit is recommended.
Treatment and therapy
The cause of neurofibromatosis lies in the genes and cannot be eliminated, thus the disease is considered incurable. Therefore, the goal and content of therapy can only be to have an early palliative effect on the symptoms that occur. Patients should seek advice from several cooperating specialists in order to be able to treat all symptoms. Depending on the severity of the disease, a team consisting of a general practitioner, who should intervene in a coordinating manner in particular, a neurologist or neurosurgeon, and an ophthalmologist is recommended. At some university hospitals there are special outpatient clinics for neurofibromatosis patients. Symptom-related treatments, such as eye surgery or interventions on the facial nerves, are performed there. A large tumor can be removed surgically, but in doing so, risks and side effects must be weighed against the chances of success.
Outlook and prognosis
Neurofibromatosis type 2 is considered incurable to date. The reason for this is found in the cause of the health disorder.There is a mutation of human genetics which, for legal reasons, may not be altered by physicians and medical practitioners. In a medical care, therefore, all measures initiated by the attending physician focus on alleviating the individually severe symptoms. In most cases, various medical specialists work together cooperatively to ensure optimal care for the patient. Together, they achieve considerable relief of the irregularities and thus a significant improvement in the general quality of life. Without treatment, an increase in symptoms is to be expected. In addition, the general risk of accidents is increased due to the disturbances in hearing as well as problems with balance. The risk of developing a secondary disease would therefore be greater than with continuous medical care. Repeated surgical interventions occur during the course of life. The aim of the operations is to remove the benign tumors before they cause complications or disturbances in movement as well as nerve activity. The affected person must therefore undergo regular check-ups throughout his or her life in order to be able to detect growths as early as possible. Their location as well as impact will be determined and preventive action will be taken if necessary.
Prevention
Hereditary diseases such as neurofibromatosis type 2 cannot be prevented. Affected individuals refraining from having children of their own is a personal preventive measure that must be weighed, but it is recommended by many practitioners, although it is not a guarantee because of the new mutations. Affected individuals should be examined at least once a year to detect and treat changes in tumors, new symptoms, and deterioration in a timely manner.
Follow-up
After treatment for neurofibromatosis type 2 has been completed, monitoring of symptoms is especially important. Particularly after surgical procedures, the affected patient must take it easy. The skin must be protected from further stress, and therefore care should be taken in both personal hygiene and clothing to avoid exposing the skin to further irritation. Particularly mild body care products and low-irritation clothing are important here. Especially mild shampoos and washing liquids with very skin-friendly pH values are very gentle here. Clothing made of soft and breathable materials also provides relief. High-quality cotton or wool, which are processed very skin-friendly, help the affected person for his well-being. Particularly attentive personal hygiene is also indicated. Parents of affected children should ensure regular replacement of bedding and keep the living environment very clean by daily cleaning of floors and surfaces. Parents should keep a close eye on the development of symptoms in order to be able to take the necessary measures immediately if complications arise. Since neurofibromatosis type 2 can often take a very severe course, it makes sense to involve a therapist. He or she can help parents cope with stress and establish contact with support groups.
Here’s what you can do yourself
In addition to surgical treatment, there are self-help blogs and self-help portals on the Internet that offer many suggestions and tips about life as a sufferer. A change in diet to anti-angiogenic foods supports the formation of tumor-supplying vessels as a preventive measure and inhibits new tumor growth. Modern technology allows adaptation to individual needs. Speech recognition programs and vibration amplifiers provide important assistance for the hearing impaired. Devices with large displays often enable those with visual impairments to read books again in the form of e-books. Learning a sign language at an early stage, in combination with appropriate interpreter services via smartphone, enables almost barrier-free communication with hearing people. In addition, there is the right to an interpreter at public offices, doctor’s appointments and in working life. Here, however, the person affected is obliged to apply for an interpreter for each of these cases at the office, the health insurance fund or the integration office. In the case of particularly marked limitations, there is also the possibility of an assistance dog, the costs of which, however, have not yet been covered by the health insurance funds or state institutions.Sufferers who also suffer from circulatory disorders in the form of polyneuropathy are helped to stimulate circulation by means of sport and blood circulation-promoting ointments. Also the renunciation of smoking and tight-fitting clothes provides for an improvement of the symptoms.
