Brown-Vialetto-Van Laere syndrome is a disease that is inherited. As part of the disease, the function of various caudal nerves in the brain is lost. Furthermore, affected patients lose their sense of hearing. In addition, a so-called spinal atrophy of the musculature develops in some of the affected individuals.
What is Brown-Vialetto-Van Laere syndrome?
Brown-Vialetto-Van Laere syndrome received its name in honor of the physicians who first described the disease according to scientific standards in 1894, 1936, and 1966. These physicians are Vialetto, Brown and van Laere. The disease is enormously rare, with the exact prevalence of Brown-Vialetto-Van Laere syndrome estimated at less than 1:1,000,000. Inheritance is autosomal recessive in approximately 50 percent of affected patients. To date, only about 60 cases of the disease have been diagnosed. It has also been shown that Brown-Vialetto-Van Laere syndrome occurs about three times more often in female patients than in men. Synonymously, the disease is also referred to as riboflavin transporter deficiency and for this reason is sometimes given the abbreviation RTD. In addition to the main symptoms, the disease often manifests itself in insufficient respiration of the affected patients. Furthermore, in many cases a so-called sensorineural hearing loss results. The development of progressive ponto-bulbar palsy is also possible.
Causes
Medical research concludes unequivocally that Brown-Vialetto-Van Laere syndrome is a hereditary disease. Accordingly, certain genetic defects or mutations are responsible for the development of the syndrome in affected individuals. In principle, doctors differentiate between two different types of the disease, which are based on different gene mutations. The first type of Brown-Vialetto-Van Laere syndrome is based on a genetic mutation on a gene called SLC52A3, while the second type of the disease is due to mutations on the SLC52A2 gene. In addition to the responsible genes, the exact localizations on the respective gene segments are also known. Both genes have in common that they play an important role in the coding of transporter proteins of riboflavin. However, their significance in the human nervous system has not yet been conclusively clarified. Patients suffer from a loss of neurons in certain nerves of the brain located near the so-called medulla oblongata. The anterior horn cells of the spinal cord are also affected by signs of degeneration. Both symptoms show up in early childhood in individuals with Brown-Vialetto-Van Laere syndrome.
Symptoms, complaints, and signs
Brown-Vialetto-Van-Laere syndrome usually begins in newborns or infants. However, in some individuals, the first symptoms do not appear until the end of the second decade of life. Initially, patients usually lose their sense of hearing on both sides. In most cases, the reason for this is found in an increasingly pronounced sensorineural hearing loss. In addition, various nerves of the brain lose their function, resulting in so-called motor deficits. These nerves include, for example, the accessorius nerve, the facial nerve and the glossopharyngeal nerve. In addition, affected individuals sometimes suffer from specific anterior horn signs in the extremities as well as general weakness of the limbs. Many patients with Brown-Vialetto-Van Laere syndrome have difficulty breathing, sagging facial skin, and retinitis pigmentosa. They may also develop optic atrophy and epileptic seizures. Bulbar paralysis is primarily responsible for weak facial muscles. Brown-Vialetto-Van Laere syndrome progresses comparatively rapidly. Other complaints of the disease include dysphagia, contractures of the ankles, and tremor.
Diagnosis and course
Brown-Vialetto-Van Laere syndrome is diagnosed by a specialized consultant. Regarding the low prevalence of the condition and the fact that it is a hereditary disease, Brown-Vialetto-Van-Laere syndrome is usually evaluated in a specialized center for genetic disorders.Since the first symptoms usually appear in children, the guardians play a crucial role in diagnosing the disease. They first consult a pediatrician and are then followed up by appropriate specialists. A family history may provide helpful information about relevant cases of the disease in the relatives. The investigation of Brown-Vialetto-Van Laere syndrome is guided by typical clinical symptoms. A combination of visual examinations, hearing tests, and neurologic examinations is used to rapidly diagnose the disease. Genetic analysis confirms the presence of Brown-Vialetto-Van Laere syndrome. Nevertheless, the treating physician obligatorily performs a differential diagnosis, excluding Nathalie syndrome, Fazio-Londe syndrome, Joubert syndrome, amyotrophic lateral sclerosis, and Madras motor neuron disease.
Complications
Affected individuals experience severe hearing loss as a result of Brown-Vialetto-Van Laere syndrome. In this case, the impairments occur in both ears and can lead to complete loss of hearing. Similarly, the patient’s motor skills are severely limited by Brown-Vialetto-Van Laere syndrome. The limitations are strongly dependent on the affected regions in the brain. In most cases, however, this causes limitations in movement and also mental status complaints. The patient may also experience epileptic seizures. As a result, the quality of life decreases considerably. The limbs are weakened and usually can no longer be moved as usual. Physical exercise or sports activities are also possible only to a limited extent. It is not possible to treat Brown-Vialetto-Van Laere syndrome causally. Treatment is targeted at alleviating and reducing symptoms. In most cases, the syndrome leads to a reduced life expectancy and thus to death more quickly. With the help of medication, the progression can only be halted. At the same time, it is not possible to directly predict how much life expectancy will be reduced by Brown-Vialetto-Van Laere syndrome.
When should you see a doctor?
Since Brown-Vialetto-Van Laere syndrome does not cure itself, a doctor should definitely be consulted when the symptoms of this syndrome appear. In this way, further complications can be avoided. As a rule, the doctor must be consulted if there is a loss of the sense of hearing without a specific reason or without injuries. This loss usually occurs very suddenly and cannot be restored by Brown-Vialetto-Van Laere syndrome. The affected persons are then dependent on a hearing aid. A visit to a doctor is also necessary in any case of motor deficits or difficulties. Brown-Vialetto-Van Laere syndrome also manifests itself in weak limbs in some cases. Urgent treatment is necessary if the syndrome already causes epileptic seizures. In the worst case, these can lead to the death of the affected person. The initial investigation of Brown-Vialetto-Van Laere syndrome can be performed by a general practitioner. Unfortunately, since there is no cure, the symptoms can only be limited. This is done with the help of medication. No other special therapy is necessary.
Treatment and therapy
Brown-Vialetto-Van Laere syndrome is treated with medication based on the symptoms. In this process, the patient receives immunoglobulins and steroids. The drugs temporarily slow down the progression of the disease. The prognosis varies greatly in individual cases. After the first manifestation of the symptoms, about 30 percent of those affected live for more than ten years. In approximately 50 percent of patients, the state of health progressively deteriorates.
Outlook and prognosis
Brown-Vialetto-Van Laere syndrome cannot be completely cured. For this reason, only symptomatic treatment can take place, although it cannot alleviate or limit all symptoms. The affected person is dependent on taking medication for the rest of his or her life. The hearing complaints can likewise no longer be treated, but in some cases they can be alleviated by the use of a hearing aid.As a rule, the health condition of the affected person deteriorates as the disease progresses, and the patient’s life expectancy is also significantly limited and reduced. After diagnosis, most patients live for about 15 years, although this life expectancy depends very much on the patient’s health condition. If Brown-Vialetto-Van Laere syndrome is not treated, life expectancy is drastically reduced and the patient dies prematurely. Due to the limited motor abilities, most patients are dependent on the help of other people in their daily lives. Due to the epileptic seizures, the affected person can die in the worst case if the seizure is not recognized and treated in time. The prognosis is very poor in this syndrome.
Prevention
Prevention of Brown-Vialetto-Van Laere syndrome is not possible because the disease is congenital. Therefore, it is particularly important to diagnose the syndrome early in affected children. An early start of therapy often delays the progression of symptoms for a certain time. In addition, this sometimes improves the prognosis of the disease.
Follow-up
In Brown-Vialetto-Van Laere syndrome, patients have very limited options for follow-up care in most cases. Because it is a hereditary disorder, it cannot be treated causally, but only purely symptomatically. For this reason, a complete cure is usually not possible, so that those affected are dependent on lifelong therapy. As a rule, the patient must take medication throughout his or her life to alleviate the symptoms. However, Brown-Vialetto-Van Laere syndrome significantly reduces the life expectancy of the affected person, so that the health condition deteriorates severely. Eventually, sufferers die from the ailments of the syndrome, which cannot be completely cured. In the event of an epileptic seizure, a doctor must be called or the hospital visited immediately. If such a seizure is not treated, patients can die from the seizure in the worst case. Since Brown-Vialetto-Van Laere syndrome is not infrequently associated with psychological symptoms, psychological treatment is often necessary. Here, contact with other sufferers of the syndrome can also have a positive effect on the disease, as it can lead to an exchange of information.
What you can do yourself
The options for self-help are very limited in Brown-Vialetto-Van Laere syndrome. There are no sufficient measures that would lead to a cure. For this reason, the focus in everyday life is on improving the quality of life. The disease is usually diagnosed immediately after birth and should be treated medically. Since children already grow up with the health restrictions, they should be informed honestly and in good time about their disease and its consequences. An open approach to the disease is helpful in everyday life to be able to answer questions, avoid misunderstandings and not feel excluded from society. Contact with other children who also have health impairments can be encouraged at an early age. At the same time, contact with healthy children must be fostered. In this way, a mutual exchange takes place and the feeling of exclusion is avoided. If the child suffers from the health disorders or shows behavioral affinities, additional psychological care should be sought. Discussions about the existing emotions can be supportive in coping with the disease. Since Brown-Vialetto-Van Laere syndrome is associated with various restrictions on sporting as well as leisure activities, those activities that can be carried out without problems should be encouraged. Thus, the joy of life is promoted and the well-being is strengthened.
