Question: What are the symptoms of Schwannomatosis ?
Answer: What are the signs and symptoms of Schwannomatosis? Signs and symptoms of the schwannomatosis often develop during adulthood between ages 25 and 30. Affected people generally have multiple schwannomas, which are benign tumors of the nervous system. In schwannomatosis, these tumors can grow along any nerve in the body, although they are less common on the vestibular nerve (vestibular schwannomas, also known as acoustic neuromas). People with vestibular schwannomas, especially those with tumors affecting the vestibular nerve on both sides of the head (bilateral), may have neurofibromatosis type 2 instead. The signs and symptoms associated with schwannomatosis vary based on the size and location of the schwannomas. The most common symptom is chronic pain, which can develop as a growing schwannoma presses on nerves or surrounding tissues. Some people may develop a mass if the schwannomas is located just beneath the skin. Others can experience neurological symptoms such as numbness; tingling; and/or weakness in the fingers and toes. The Human Phenotype Ontology provides the following list of signs and symptoms for Schwannomatosis. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abnormality of the skin - Abnormality of the vertebral column - Autosomal dominant inheritance - Incomplete penetrance - Meningioma - Schwannoma - Somatic mutation - Spinal cord tumor - Variable expressivity - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: Is Schwannomatosis inherited ?
Answer: Is schwannomatosis inherited? Approximately 15% percent of all schwannomatosis cases are thought to be inherited. In these cases, the condition is thought to be inherited in an autosomal dominant manner with highly variable expressivity and reduced penetrance. This means that a person only needs a change (mutation) in one copy of the responsible gene in each cell to have a genetic predisposition to the tumors associated with schwannomatosis. In some cases, an affected person inherits the mutation from an affected parent. Other cases may result from new (de novo) mutations in the gene. These cases occur in people with no history of the disorder in their family. People with an inherited form of schwannomatosis have a 50% chance with each pregnancy of passing the condition on to the next generation.
Source: GARD

Question: How to diagnose Schwannomatosis ?
Answer: How is schwannomatosis diagnosed? A diagnosis of schwannomatosis is often suspected based on the presence of characteristic signs and symptoms, especially if there are other family members with the condition. Additional testing can then be ordered to further support the diagnosis and rule out other conditions with similar features (namely, neurofibromatosis type 2). This may include: Tumor pathology confirming that the growths are, in fact, schwannomas Imaging studies, such as an MRI examining the vestibular nerve. It is important to rule out the presence of bilateral (affecting both sides) vestibular schwannomas which would be suggestive of neurofibromatosis type 2 rather than schwannomatosis Genetic testing for a change (mutation) in the SMARCB1 or LZTR1 genes. Unfortunately, genetic testing is not informative in all people affected by schwannomatosis.
Source: GARD