Question: What are the symptoms of Fatal familial insomnia ?
Answer: What are the signs and symptoms of Fatal familial insomnia? The first signs and symptoms of fatal familial insomnia (FFI) generally develop in midlife (40s to 50s) and may include insomnia that worsens over time and vivid dreams when sleep is achieved. As the disease progresses and disturbs the autonomic nervous system (the part of the nervous system that controls involuntary actions), affected people may experience: Elevated blood pressure Episodes of hyperventilation Excessive tearing Sexual and/or urinary tract dysfunction Change in basal body temperature Decreased ability to gaze upwards Jerky eye movements Double vision Dysarthria Many people also develop ataxia (the inability to coordinate movements) which is characterized by a jerky, unsteady, to-and-fro motion of the middle of the body (trunk); an unsteady gait (walking style); and/or uncoordinated movements of the arms and legs. Advancing disease leads to more severe insomnia, worsening ataxia, and confusion. Ultimately, FFI is fatal within a few months to a few years after the development of symptoms. The Human Phenotype Ontology provides the following list of signs and symptoms for Fatal familial insomnia. 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) Adult onset - Apnea - Ataxia - Autosomal dominant inheritance - Childhood onset - Constipation - Dementia - Diplopia - Dysarthria - Dysautonomia - Dysphagia - Fever - Hyperhidrosis - Insomnia - Myoclonus - Neuronal loss in central nervous system - Urinary retention - Weight loss - 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 Fatal familial insomnia inherited ?
Answer: How is fatal familial insomnia inherited? Fatal familial insomnia (FFI) is inherited in an autosomal dominant manner. This means that to be affected, a person only needs a change (mutation) in one copy of the responsible gene in each cell. 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. A person with FFI has a 50% chance with each pregnancy of passing along the altered gene to his or her child.
Source: GARD

Question: How to diagnose Fatal familial insomnia ?
Answer: Is genetic testing available for fatal familial insomnia? Yes, genetic testing is available for PRNP, the gene known to cause fatal familial insomnia (FFI). Carrier testing for at-risk relatives and prenatal testing are possible if the disease-causing mutation in the family is known. The Genetic Testing Registry (GTR) is a centralized online resource for information about genetic tests. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional. How is fatal familial insomnia diagnosed? A diagnosis of genetic prion disease is typically made based on a combination of the following: Various, adult-onset neurologic signs and symptoms Neuropathologic findings (diagnosis made by examining cells and tissues of the brain under a microscope) A family history consistent with autosomal dominant inheritance PRNP disease-causing mutation The PRNP gene is the only gene in which changes (mutations) are known to cause genetic prion diseases, including fatal familial insomnia. Finding a mutation in this gene is necessary to confirm a diagnosis in a person with symptoms. Testing of the PRNP gene may not detect all disease-causing mutations, so if a mutation is not found, a person may still have the disease. Other studies such as EEG, brain imaging, or examining cerebrospinal fluid may be helpful in supporting a diagnosis, but none of these can diagnose a genetic prion disease on its own.
Source: GARD