Tay Sachs Disease.pdf

Tay Sachs Disease Tay-Sachs Overview ─ Tay-Sachs disease is a rare genetic disorder passed from parents to child. ─ It's caused by the absence of an enzyme that helps break down fatty substances. ─ These fatty substances, called gangliosides, build up to toxic levels in the brain and spinal...

Tay Sachs Disease Tay-Sachs Overview ─ Tay-Sachs disease is a rare genetic disorder passed from parents to child. ─ It's caused by the absence of an enzyme that helps break down fatty substances. ─ These fatty substances, called gangliosides, build up to toxic levels in the brain and spinal cord and affect the function of the nerve cells. ─ In the most common and severe form of Tay-Sachs disease, signs and symptoms start to show up at about 3 to 6 months of age. As the disease progresses, development slows and muscles begin to weaken. Tay-Sachs Overview ─ Over time, this leads to seizures, vision and hearing loss, paralysis, and other major issues. Children with this form of Tay-Sachs disease typically live only a few years. ─ Less commonly, some children have the juvenile form of Tay-Sachs disease and may live into their teen years. Rarely, some adults have a late-onset form of Tay- Sachs disease which is often less severe than forms that begin in childhood. ─ If you have a family history of Tay-Sachs disease or if you're a member of a high- risk group and plan to have children, health care providers strongly recommend genetic testing and genetic counselling.  Genetic basis Tay-Sachs is an autosomal recessive disease caused by mutations in both alleles of a gene (HEXA) on chromosome 15. HEXA gene codes for the alpha subunit of the enzyme β-hexosaminidase A, an enzyme found in lysosomes. Hex-A is responsible for breaking down a fatty substance called GM2 ganglioside. The mutations in the HEXA gene can result in reduced or absent activity of the Hex-A enzyme. As a consequence, GM2 ganglioside accumulates within nerve cells into toxic levels, leading to their progressive degeneration and death. Affected individuals inherit two copies of the mutated HEXA gene, one from each parent. Individuals who carry only one mutated copy of the gene are known as carriers and typically do not show symptoms of the disease. However, carriers can pass the mutated gene on to their children, increasing the risk of Tay-Sachs disease in future generations.  What does it mean to be a Tay-Sachs carrier? If two people who carry the genetic variant have a child, the child’s risk of developing the condition is as follows: A 25% (1 in 4) chance that the child won’t inherit any variant HEXA genes. The child won’t have Tay-Sachs disease or be a carrier. A 50% (1 in 2) chance that the child gets a variant gene from one parent. When this happens, the child will be a carrier but won’t have Tay-Sachs disease. As they’re a carrier, they may pass it on to their children. A 25% (1 in 4) chance that the child gets a variant gene from both parents. In this case, the child has Tay-Sachs disease. What are the types of Tay Sachs Disease? There are three forms of Tay-Sachs: 1. Infantile Tay-Sachs this is the most common form, it develops soon after a baby is born and causes death early in childhood; often pass away before the age of 5. 2. Juvenile Tay-Sachs this affects children ages 2 and older and progresses more slowly than the infantile form, children don't live beyond their mid-teens; they have a life expectancy into early adulthood. 3. Late-onset Tay-Sachs this is very rare and can start between puberty and the mid-30s. It is a milder form of Tay-Sachs, some people who have this form may live a normal lifespan. Symptoms and Causes Symptoms vary in severity and types of Tay Sachs disease and may become more pronounced as the disease progresses. The common symptoms associated with Tay-Sachs disease are: 1. Developmental delay 2. Muscle weakness 3. Loss of motor skills 4. increased startle response 5. Hypotonia 6. Seizures 7. Vision and hearing loss 8. Cherry-red spot on the retina  How is Tay Sachs disease diagnosed? To confirm that your child has Tay-Sachs disease, your health care provider will ask about symptoms and any family hereditary disorders, and also do a physical exam. Your child may need to see a neurologist and an ophthalmologist for nervous system and eye examinations. The diagnostic test are: 1. HEX-A blood test: The blood test checks the levels of hexosaminidase enzyme in the blood. People with the infantile form will have no or extremely low levels of HexA, while those with the juvenile or late-onset form may retain levels of 10–15%. 2. Genetic testing: This test can examine the HEXA gene to identify whether there are changes that indicate Tay-Sachs disease. 3. Eye exam: During an eye exam, the health care provider may see a cherry- red spot in the back of the eyes, which is a sign of the disease. Can Tay-Sachs be treated? ─ Treatment for Tay-Sachs disease is supportive of your child’s symptoms. For example, your healthcare provider may prescribe medication to manage seizures. Other treatment measures include providing proper nutrition and hydration. Your child’s provider will make them as comfortable as possible. ─ In addition, your healthcare provider can help you and your family prepare for the loss of your child. They may recommend visiting a mental health professional or participating in a bereavement support group. Is there a cure for Tay-Sachs disease? No, there isn’t a cure available for Tay Sachs disease.  Supportive treatments for Tay Sack patient: Medication. A number of prescription medications are available to reduce symptoms and prevent complications: for example, anti-seizure medications or antibiotics for infection. Respiratory care. Accumulated mucus in the lungs is common and results in a high risk of lung infections that cause breathing problems. Chest physiotherapy (CPT), exercise and other techniques can help remove mucus from the lungs. Medications to reduce saliva production and positioning techniques are also options to reduce the risk of mucus accumulation and prevent aspiration pneumonia. Nutrition and hydration. Your child may have trouble swallowing or develop respiratory problems by inhaling food or liquid into the lungs while eating. To prevent those problems, your doctor may recommend an assistive feeding device such as a feeding tube. A feeding tube may be inserted through your child's nose and into the stomach, or a surgeon may surgically insert a feeding tube directly into the stomach (gastrostomy tube). 11 Can Tay-Sachs be prevented? Prevention of Tay-Sachs disease involves genetic counseling and testing. It is important for individuals who are carriers of the Tay-Sachs gene to receive counseling before starting a family to understand the risks and options available. Genetic testing can help identify carriers and provide information for family planning decisions. Genetic testing is a process that involves analyzing a person's DNA to look for specific changes or mutations in genes. It can be done through a simple blood test or a cheek swab. The sample is then sent to a laboratory where scientists examine the DNA to check for any genetic abnormalities or mutations, such as the Tay-Sachs gene. Oral and Dental manifestations Tay-Sachs disease is a rare genetic disorder that primarily affects the nervous system. While its direct connection to dentistry might not be obvious, individuals with Tay-Sachs disease may have specific dental considerations due to their condition.  Oral and Dental Manifestations 1. Tooth eruption can still occur, but it may be delayed or different compared to individuals without the condition. 2. Dental caries also known as tooth decay, Factors such as difficulties in maintaining oral hygiene and potential dietary challenges can contribute to a higher incidence of dental caries. 3. Periodontal disease also known as gum disease, can be a concern for individuals with Tay- Sachs disease. Due to difficulties in maintaining oral hygiene, there may be an increased risk of gum inflammation and infection.  Dental management 1. Special care: Dentist need to be gentle and careful during check-ups and treatments. 2. Prevention: Regular cleanings and fluoride treatments can help stop tooth problems before they start. 3. Using Anesthesia Safely: Dentists need to be careful when giving medicine to make sure patients don’t feel pain or have trouble swallowing. 4. Working Together: Dentists and doctors should work together to plan the best care for patients with Tay-Sachs disease. References Tay-Sachs disease. Genetic and Rare Diseases Information Center. National Health Services (U.K.). Tay-Sachs Disease National Organization for Rare Disorders, Inc. Tay Sachs Disease Tay-https://www.mayoclinic.org/diseases-conditions/tay-sachs-disease/symptoms-ca https://medlineplus.gov/genetics/condition/tay-sachs-disease/#references https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/tay-sachs-di https://rarediseases.org/rare-diseases/tay-sachs-disease/#synonyms https://www.ncbi.nlm.nih.gov/books/NBK22250/ https://www.mayoclinic.org/diseases-conditions/tay-sachs-disease/diagnosis-treatment/drc-20378193 https://www.medicalnewstoday.com/articles/tay-sachs-disease https://my.clevelandclinic.org/health/diseases/14348-tay-sachs-disease https://www.columbiadoctors.org/health-library/condition/tay-sachs-disease/ Sachs disease information page. National Institute of Neurological Disorders and Stroke