Phenylketonuria (PKU) is a condition in which the body cannot break down one of the amino acids found in proteins. PKU is considered an amino acid condition because people with PKU cannot break down the amino acid called phenylalanine. If left untreated, PKU can cause brain damage or even death.our baby will need to be on a restricted diet to avoid phenylalanine, a building block of proteins that individuals with phenylketonuria (PKU) cannot break down. Phenylalanine is found in all foods that contain protein and also in artificial sweeteners.
In diagnosing hypothyroidism, your doctor will take into account both your symptoms and the results of a thyroid stimulating hormone (TSH) test. In essence, hypothyroidism is the result of diminished levels of thyroid hormonesâknown as T3 and T4.
The most common blood test for hypothyroidism is thyroid-stimulating hormone (TSH). TSH is the most sensitive test because it can be elevated even with small decreases in thyroid function. Thyroxine (T4), the main product of the thyroid gland, may also be measured to confirm and assess the degree of hypothyroidism.