highphenylalanine

High phenylalanine refers to an elevated level of the amino acid phenylalanine in the blood. Phenylalanine is an essential amino acid, meaning the body cannot produce it and must obtain it from dietary protein. It is a building block for proteins and is also a precursor for neurotransmitters like dopamine, norepinephrine, and epinephrine.

Typically, high phenylalanine levels are associated with phenylketonuria (PKU), a rare inherited metabolic disorder. In PKU, a deficiency in the enzyme phenylalanine hydroxylase prevents the body from properly breaking down phenylalanine. This leads to a buildup of phenylalanine in the blood and tissues, which can be toxic to the brain if left untreated. Symptoms of untreated PKU can include intellectual disability, seizures, behavioral problems, and skin rashes.

Diagnosis of PKU is usually made through newborn screening tests. Treatment involves a strict low-phenylalanine diet, which limits foods high in protein such as meat, fish, eggs, dairy products, and nuts. Special medical formulas are used to ensure adequate protein and nutrient intake while keeping phenylalanine levels within a safe range. Lifelong adherence to the diet is crucial for individuals with PKU to prevent neurological damage.

While PKU is the most common cause of high phenylalanine, other less common conditions can also lead to elevated levels. These can include certain liver diseases or deficiencies in other enzymes involved in phenylalanine metabolism. In some cases, temporarily elevated phenylalanine levels can occur during pregnancy, known as maternal PKU, which can pose risks to the developing fetus if not managed carefully.