Phenylketonuria - Condition and Symptoms
Phenylketonuria (PKU) is a rare, inherited condition in which a baby is born deficient in the enzyme phenylalanine hydroxylase. This enzyme is necessary for the body to break down an amino acid called phenylalanine. A build up of phenylalanine in the body is toxic to the central nervous system and can cause brain damage and mental retardation.
Phenylalanine is a substance found in high protein foods such as meat, chicken, fish, eggs, nuts, cheese, legumes, and dairy products. Although a person with PKU can eat starchy foods such as potatoes, bread, pasta, and corn, the intake of these types of food must be closely monitored. The artificial sweetener Aspartame contains phenylalanine, and must be avoided.
Classic PKU is the most severe form of this condition. Untreated classic PKU results in permanent mental retardation. Mild or moderate PKU presents less of a risk for brain damage, but persons with mild or moderate PKU must still follow a restricted diet to avoid mental retardation and other complications such as ADHD.
It is vital that infants with PKU be diagnosed at birth, so the special low phenylalanine diet can be followed immediately. If left untreated, PKU causes brain damage or mental retardation within one year of birth. Babies with PKU can be breast fed in order to receive all the benefits of breast milk, but even the intake of breast milk must be monitored. The baby must also be given a special formula to supplement the breast milk.
Although doctors formerly advised their PKU patients that they could go off the restricted diet in their teens, newer research recommends that all persons with PKU remain on the diet for life in order to improve mental functioning and behavior. Adults with PKU will also suffer from continuing damage to the central nervous system if they do not follow the low-phenylalanine diet.
Women with a history of PKU must follow the low-phenylalanine diet before and during pregnancy, because even if their unborn child has not inherited the gene, the build up of phenylalanine in the mother can cause damage to the fetus. There is also an increased chance of miscarriage in women with PKU.
PKU is screened routinely by a simple blood test typically done at birth and again at about two weeks of age. Most states require this screening for all newborns. If this test is positive for PKU, the diagnosis is confirmed with other blood and urine tests.
There are no obvious symptoms in newborns with Phenylketonuria. However, without treatment symptoms develop within the first year of life. Symptoms can be mild or severe. They include mental retardation, seizures, tremors or jerky movements of the arms and legs, stunted growth, eczema, an abnormally small head, strange positioning of the hands, a musty smell, and extremely fair skin, eyes, and hair due to the fact that phenylalanine cannot transform into melanin. Later in childhood, children with PKU may exhibit behavioral problems or ADHD (hyperactivity). Symptoms of PKU can be mild to severe.
Treatment of PKU is almost entirely limited to the strict adherence to a diet extremely low in phenylalanine. The diet is particularly crucial during a child’s growing years. Supplements such as iron, carnitine, and fish oil are often recommended. Fish oil replaces the fatty acids missing from a standard phenylalanine-free diet, and is believed to improve nervous system development. Adherence to this diet has proven very effective in allowing people with Phenylketonuria to manage the condition.
Back to topFiling for Social Security Disability with a Phenylketonuria Diagnosis
The Social Security Administration (SSA) addresses Phenylketonuria under Section 10.00 of the Blue Book, Multiple Body Systems. Phenylketonuria is specifically listed as an impairment that can cause interruption of normal body function and development under Section 10.00, Paragraph C.2.
Because the degree of impairment caused by PKU varies widely from person to person, the SSA evaluates the specific effects of PKU on an individual basis to determine whether you have the residual functional capacity to engage in substantial gainful activity. In other words, when you apply for disability benefits, you must show that your PKU is severe enough to prevent you from working, and you will need medical records to support your case. If PKU has resulted in impairments of other body systems, the SSA also takes into consideration those impairments. Therefore, your documentation should include not only medical records that diagnose and document PKU, but also records that diagnose and document all side effects or complications arising from PKU. These records should show the effects PKU and any complications arising from PKU that affect your daily life.
Back to topYour Phenylketonuria Disability Case
If you are disabled because of Phenylketonuria that is so severe it prevents you from working, you may well be entitled to Social Security Disability benefits. Although total disability based on a diagnosis of Phenylketonuria can be difficult to prove compared to other disabling conditions since there are no specific medical guidelines for this condition in the Blue Book, working closely with medical professionals and a qualified Social Security Disability attorney or advocate to collect and present the appropriate documentation to support your disability claim in front of the Disability Determination Services (DDS) can help ensure that your Phenylketonuria disability case will have the highest possible chance of success.
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