4-hydroxyphenyllactate is a tyrosine metabolite. Tyrosine is an amino acid. Amino acids are the building blocks of protein. The body makes tyrosine from another amino acid called phenylalanine.
Among other food items, tyrosine can also be found in:
- meats,
- fish,
- eggs,
- dairy products (cheeses, etc).
4-hydroxyphenyllactate is present in relatively higher concentrations in the cerebrospinal fluid and urine of patients with phenylketonuria (PKU) and tyrosinemia.
What is phenylketonuria (PKU)?
Phenylketonuria (commonly known as PKU) is an inherited disorder that increases the levels of a substance called phenylalanine in the blood. Phenylalanine is a building block of proteins (an amino acid) that is obtained through the diet.
What is tyrosinemia?
Tyrosinemia is a genetic disorder characterized by disruptions in the multistep process that breaks down the amino acid tyrosine, a building block of most proteins. If untreated, tyrosine and its byproducts build up in tissues and organs, which can lead to serious health problems.
4-hydroxyphenyllactic acid is often used to help diagnose rare genetic metabolic disorders. 4-hydroxyphenyllactic acid can sometimes be also slightly elevated in other conditions or due to intake of tyrosine-rich foods.
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