PKU (Phenylketonuria)

PKU is an abbreviation for Phenylketonuria. Children born with this rare genetic disorder cannot metabolize a part of the protein in food called Phenylalanine (PHE). Without treatment, PHE levels are markedly increased in the blood. As a result, brain development and function are seriously impaired. If untreated, PKU children may appear normal for their first few months of life, but will usually become mentally retarded before they are one year old.Today, hospitals test all newborn babies for elevated levels of PHE. When a newborn is diagnosed with PKU, the baby is immediately placed on a low PHE diet and treated for PKU.


The treatment of PKU is dietary. Much research has been conducted over the years and experts agree that a PKU patient who adheres to a strict low PHE diet for life should develop normally. This diet includes a special low PHE formula, low protein foods, fruits and most vegetables. Food items to be avoided include meat, fish, poultry, dairy products, bakery goods and eggs because they contain high levels of PHE. While adherence to this diet is critical for normal developmental growth, it is very challenging for the patient and parents for a number of reasons: The low PHE formula requires specific daily intake and is important. Blood tests are necessary to monitor blood levels of PHE. Costs of purchasing low protein foods are significant as PKU children grow older, peer pressure to fit in and not be different increases, and children face emotional challenges with their special diet and condition. Constant calculating of PHE levels in foods is challenging and can be tedious.


The understanding of PKU is an on-going process. This fact is most evident with Maternal PKU. Maternal PKU is a syndrome known to cause severe birth defects in children born to mothers with PKU who are not maintaining safe PHE levels through strict dietary controls during pregnancy. Offspring with the syndrome may demonstrate or suffer growth retardation, microcephaly, congenital heart disease and other serious anomalies. Intensive research and education programs focused on Maternal PKU are attempting to better understand this serious situation.