Classical phenylketonuria is a rare genetic disorder that affects the body's ability to process a specific amino acid. The word "phenylketonuria" is pronounced as /fɛnɪlkɛtoʊnurɪə/, with emphasis on the second syllable. The "ph" in "phenyl" is silent, and the "k" is pronounced as "c". Classical phenylketonuria is typically diagnosed in newborns through routine genetic testing, and early intervention is critical in preventing developmental delays and intellectual disabilities associated with the condition.
Classical Phenylketonuria (PKU) is a rare genetic disorder characterized by the inability to metabolize phenylalanine, an essential amino acid found in most foods. It is caused by a deficiency of the enzyme phenylalanine hydroxylase (PAH), which is responsible for converting phenylalanine into other molecules that the body can use.
Individuals with classical PKU lack or have significantly reduced levels of this enzyme, leading to the accumulation of phenylalanine in the blood and tissues. This elevated level of phenylalanine can cause damage to the central nervous system if not managed properly.
Symptoms of classical PKU typically manifest during infancy or early childhood and may include intellectual disability, delayed development, seizures, behavioral problems, and a musty odor in the breath, urine, or sweat. Without treatment, these symptoms can progressively worsen over time.
The primary treatment for classical PKU involves a strict and lifelong adherence to a low-phenylalanine diet. This specialized diet involves restricting foods high in phenylalanine, such as meat, fish, eggs, dairy products, grains, and certain fruits and vegetables, while consuming specially formulated phenylalanine-free medical foods to meet nutritional needs.
Early diagnosis through newborn screening programs and prompt initiation of treatment is crucial to prevent complications associated with classical PKU. With early intervention and continuous management, individuals with classical PKU can lead relatively healthy lives and minimize the risk of cognitive impairment and developmental disabilities.
The word "classical phenylketonuria" is composed of two main components: "classical" and "phenylketonuria".
"Classical" refers to something that is traditional, typical, or characteristic of a particular form or style. In the context of phenylketonuria (PKU), it signifies the most common and severe form of the disease.
"Phenylketonuria" is a compound word formed by combining three components: "phenyl", "ketone", and "uria".
- "Phenyl" stems from the word "phenylalanine", which is an amino acid found in proteins present in many foods.
- "Ketone" refers to a type of organic compound characterized by a carbonyl group (a carbon-oxygen double bond) in its structure.
- "Uria" refers to a condition or presence of a substance in urine.