Anticonvulsant Medications Treating Tay-Sachs Disease

                 Tay-Sachs Disease cannot be cured, but there are medications out there to help treat the symptoms of this condition and make the patient more comfortable. Many infants that are affected with Tay-Sachs Disease have seizures and there are anticonvulsant medications out there to help these infants avoid having clonic-tonic or grand mal seizures. The prescriptions given to these infants are very similar if not the same for those people affected with epilepsy.

                One of the most common medications given to those that have Tay-Sachs Disease is Tegretol or carbamazepine. This medication comes in chewable tablets of 100 mg, tablets of 200 mg, and extended-release tablets of 100 mg, 200 mg, and 400 mg. This is a common medication given to individuals who have seizures. It helps to prevent seizures before they start and though it works well for this, it does have many precautions and possible side effects. Tegretol should not be used if the individual has allergies to other anticonvulsant medications, has bone marrow problems, or certain blood disorders such as acute intermittent porphyria. This medication often times causes dizziness and drowsiness and makes the patient more sensitive to the sun which may lead to higher chances or severity of sun burns. A serious skin condition can result in using this medication.

                Another anticonvulsant medication used is Dilantin or phenytoin for seizure treatment and prevention. Dilantin only comes in a 100 mg extended oral capsule. This is also a common anticonvulsant medication. As with any drug or medication, there is always the possibility of an extreme allergic reaction, especially if the patient is already known to be allergic to other anticonvulsant medications. This may not be an appropriate treatment for those that use alcohol, have liver problems, have certain blood disorders, have lupus, have a vitamin B-12 deficiency, and/or have diabetes. The most common side effects are dizziness and drowsiness, and also swelling and bleeding of the gums of the mouth.

                Depakine which is known as valproic acid is another medication that may be prescribed to control seizures in Tay-Sachs patients. This medication comes in a 250 mg liquid-filled capsule and also as a liquid solution. This may not be an appropriate drug for those that have liver disease, kidney disease, pancreatitis, and/or certain metabolic disorders and conditions. As with most anticonvulsant medications, drowsiness and dizziness may occur and are common. There are some very serious, possible side effects that may occur and include hepatotoxicity- which has a higher risk of occurring in those patients younger than two years old, teratogenicity effects such as neural tube defects and spina bifida, and pancreatitis.

                These are common medications given to those who have been diagnosed with Tay-Sachs Disease, but there are more and varied anticonvulsant medications that may be more beneficial for a particular patient. You should consult with your doctor about what kind of anticonvulsant medication would be best, in what dosage, for how long, and even if it is a wise decision to start the use of an anticonvulsant medication for an individual suffering from Tay-Sachs in the first place. More information can be found about the medications discussed above, as well as other options, online at http://www.rxlist.com/script/main/hp.asp     

Testing for Tay-Sachs Disease

                Now that we know more about Tay-Sachs disease as far as how it affects the body and who has a higher risk of inheriting the genetic mutation, how does one test for such a condition? Is there a test that can tell you if you have a child with Tay-Sachs? Can the test tell if a potential parent is a carrier of the disease, and if such a test exists, where can you go to have it done?

                Though Tay-Sachs disease is an awful condition, fortunately there is a test available to find out if your child may have Tay-Sachs, and to also see if you’re an adult who is a carrier of the genetic mutation. It is a simple blood test that measures hexosaminidase A (hex A) enzyme levels (look at my first post on this blog to see more on how hex A relates to Tay-Sachs). The test can be done on a baby who is suspected of having Tay-Sachs, and can also be used for adults suspected of being carriers. This blood test can be done from extracting blood from a vein, the umbilical cord, amniotic fluid, and even the placenta.

                A healthy baby inherits a gene from each parent that codes for the proper amount of hex A to be made. If the baby inherits only one gene that codes properly from one parent, and the other gene is mutated so that hex A is not made properly from the other parent, then that baby is said to be a carrier of the disease. An adult can go through life without ever knowing they were a carrier for Tay-Sachs, so this test would be appropriate for an adult that has had a family history of Tay-Sachs, or their partner is a carrier or has a family history, as well. This is the test recommended for potential parents who are worried about having a baby with Tay-Sachs. If a baby inherits a mutated gene from each parent who is obviously a carrier, or even affected with Late-Onset Adult Tay-Sachs, then that baby will have Tay-Sachs disease. This test would be administered if the baby begins showing signs of Tay-Sachs (please see my previous posts on this blog to read the signs and symptoms of Tay-Sachs disease in infants under 6 months old).

                If you want to have this test done on you, your baby, or even your unborn infant, it is best to speak with your doctor about why you want to have it done. Also, there is a possibility your family doctor or OB/GYN can administer the test and have it sent out or tested at their lab. The prenatal test can be done around the eleventh week of pregnancy.

                This is a helpful, easy test to find out if you are a carrier, or if your baby has Tay-Sachs. Secondary genetic tests are suggested if you come up positive for being a carrier, or if your baby has it, or even if you may be developing the Late-Onset Tay-Sachs disease. For more information on available tests, take a look at: http://www.webmd.com/parenting/baby/tay-sachs-test

               

               

The Prevalence of Tay-Sachs Disease in Certain Populations

Tay-Sachs Disease is a rare genetic condition with about 1 in 200 people being carriers. This statistic is not the same for all populations, though, as it is estimated 1 in about 30 people of Ashkenazi Jewish ethnicity or descent carry the disease in their genes. Ashkenazi Jews tend to be from Eastern and/or Central Europe.  There are some other ethnic populations that tend to have higher carrier rates and an increased frequency of the disease such as French Canadians, those of Irish ethnicity, and Louisiana Cajuns.

                The reason why Tay-Sachs Disease is more common in the Ashkenazi Jewish population is due to the fact that many Jews prefer to marry others of Jewish descent for both political aspects, as well as religious reasons. Since Tay-Sachs Disease is an autosomal recessive genetic condition, it is required that both the mother and father of the child be carriers of the disease. If indeed both parents are carriers of Tay-Sachs, there is a ¼ or 25% chance that the child will be affected with Tay-Sachs Disease, itself. If one parent has the disease and the other parent is a carrier, there is a ½ or 50% chance that the baby they have will exhibit Tay-Sachs. Since this ethnic group has a high carrier rate, they are more likely to have an affected baby. This is why it is important to have genetic testing performed before having a baby if you have a family history of Tay-Sachs, or are of Ashkenazi Jewish ethnicity, are French Canadian, are Irish, and/or are Louisiana Cajun.

                There are some other theories that suggest why this Jewish population has such a high carrier rate. One theory is called the Founder Effect. Many people alive today that are Ashkenazi Jewish or descended from it, can trace their ancestry to a select “founder” group of a few thousand Jews that lived in the area of Eastern Europe around 500 years ago.  If this is the case, the mutation probably started back then and has since become more common and passed on more often within that population resulting in higher carrier rates.

                Another theory says perhaps the reason why the Tay-Sachs Disease gene increased in this population is because it has a certain evolutionary benefit or advantage. Maybe being a carrier of Tay-Sachs can help prevent a specific illness or condition similar to the fact that if a person is a carrier of sickle-cell anemia, they are immune from malaria. Some scientists say that there is a chance that being a carrier of Tay-Sachs Disease could make you immune from tuberculosis or TB. However, there has been no strong evidence for this, though additional research is being conducted to find other possibilities.

                There are some other genetic diseases that are quite frequent in the Ashkenazi Jewish people. They include, but are not limited to, Torsion Dystonia, Niemann-Pick Disease, Crohn’s Disease, Canavan Disease, and Bloom Syndrome. For more information about Tay-Sachs Disease frequency in this ethnic group, as well as more information on the theories discussed above, go to: https://www.23andme.com/health/tay_sachs/

An Overview of Tay-Sachs Disease

                Tay-Sachs Disease is a fatal autosomal recessive genetic condition. It is caused by an inactivity of the beta-hexosaminidase A enzyme which aids in the breakdown of gangliosides. This leads to the harmful buildup of ganglioside GM2, a fatty substance that is made and broken down very rapidly during infancy. The genetic mutation can be found on chromosome 15. The only way a child can develop this disease is if both of their parents are carriers and/or affected with Tay-Sachs Disease. It is recommended that those couples who are planning to start a family and have a family history of Tay-Sachs, have genetic testing and counseling.

                
               There are three types of this disease- Infant, Juvenile, and Late-Onset Adult. The Infant type is the most common of the three and most often develops when the baby is three to six months old. This type of Tay-Sachs usually results in the child dying before the age of four. Juvenile is the next most common and occurs around age, ten. Life expectancy of those patients with Juvenile Tay-Sachs usually pass away by the age of fifteen years old. The Late-Onset Adult Tay-Sachs is the rarest of the three and develops in the adult years.

                Common symptoms of Tay-Sachs disease include loss of muscle tone, mental retardation, decreased social skills, irritability, deafness, slowed growth, loss of motor skills, red spots on the eyes, inability to swallow, and blindness. More rare symptoms are seizures, dementia, and paralysis. As a patient with Tay-Sachs continues to develop, the symptoms usually tend to get worse and lead to death. Most commonly, lung infections take the lives of those affected with Tay-Sachs Disease.

                There is no known cure for Tay-Sachs, but medications may be prescribed to help keep the patient comfortable.  Some medications include anticonvulsants for seizures and pain medications. Prescribing a very nutritional diet and hydration plan can prolong a patient’s life. A feeding tube may be used when the patient has lost the ability to swallow and breathing tubes are also useful to help those with Tay-Sachs breathe and avoid infections of the lungs. Chest Physiotherapy relieves the patient of mucus, which may also contribute to lung infections. Physical therapy may be used to slow the stiffening of joints and maintain muscle tone.  There is research being done on gene therapy, stem cell transplantation, substrate reduction therapy, and the possible benefits of Zavesca and Pyrimethamine (PYR) medications.

                Tay-Sachs is considered a rare genetic disease, though it is estimated that 1 out of every 200 people carry the mutated gene. It is a serious condition that needs more attention and awareness.