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.
1 When the hormone levels are low, the brain sends a message to send out TSH. 2  This causes the thyroid gland to send out more hormones. 3  If blood levels of thyroid hormone are high, the brain senses this and sends a message to stop producing TSH. 4  TSH is a very good test to check for hypothyroidism.hyroid Blood Tests. The thyroid is a gland located in the neck. Itâs job is to take iodine from the blood and combine it with an amino acid (one of the building blocks of protein) to form thyroid hormones. One of the hormones, thyroxine, is responsible for your metabolism.