Detecting PKU Early: Understanding the Common Signs and Symptoms

Are you worried about the possibility of your loved one having PKU? Do you hear conflicting medical opinions regarding a PKU diagnosis?

If so, managing PKU can be a bit of a challenge for concerned parents and patients. PKU doesn’t always manifest in the same way in everyone, besides a few key resemblances shared among patients.

Furthermore, PKU is a lifelong condition. There are clinical treatment plans that can help patients manage their symptoms better.

Without further ado, let’s dive into the common signs of PKU. Upon getting a clearer perspective on the PKU signs, you’ll know when to seek treatment and also learn how to best manage the condition.

What is Phenylketonuria or PKU?

Phenylketonuria (commonly abbreviated as PKU) is a rare condition wherein there’s an abnormally high count of an amino acid called phenylalanine in the body. It’s an inherited condition and is passed down when one or both parents have a mutated phenylalanine hydroxylase (PAH) gene.

When the PAH gene is mutated, it can cause a build-up of phenylalanine due to an inability of the body to break the enzyme down. Phenylalanine is typically derived from protein-rich diets, and when PKU patients don’t follow a restricted diet, they can suffer from lifelong consequences such as developmental delays.

In a vast majority of cases, PKU appears during the first months of life. Symptoms of childhood PKU are noticed in the early weeks of childbirth. This is because PKU is inheritable and the symptoms appear early—so screening your child is a necessary precaution if the parents have already been formally diagnosed.

That said, there are a few rare cases wherein adult-onset PKU can still occur, so don’t immediately feel that you or your family has passed through the worst of it. These cases resemble other neurological diseases like dementia, ataxia, and other behavioural problems.

Want to read up on this condition in more depth? Learn more about PKU.

Diagnosing PKU: The Steps

PKU is a fairly common genetic disorder, with 1 in 10,000 children in Australia being diagnosed with the condition. A blood test is typically administered by nurses on newborn children a few days after birth. This screening is the first step to detect any abnormalities, including PKU.

If the mother did not give birth in a hospital setting, they’re encouraged to let their child undergo this standard screening procedure at the soonest convenience.

The purpose of this blood test is to screen for any genetic disorders. This includes the detection of the enzyme phenylalanine.

If the results are a hit, then the doctors may conduct additional tests within six weeks of the child’s birth. If the results further confirm the absence of this enzyme, the doctor will inform the parents and any relevant parties.

Treatment, such as a special milk formula, will also be given right away to reduce the risk of further health complications. With proper treatment and follow-through, patients and kids with PKU can live healthy lives if they adhere to their prescribed diets and medical advice.

4 Common Signs of PKU

If treatment starts early, PKU can definitely be controllable. However, it can be detected and become progressively worse if left untreated. Here are some of the more common signs associated with PKU.

1) Lighter Skin and Blue Eye Colour

Does the patient have fair skin and blue eyes? If they do, and if the siblings don’t have those features, it could be an indication that the patient has PKU.

While having such features isn’t a conclusive sign of PKU, it’s still something to watch out for. People with PKU suffer from a genetic mutation that makes it difficult to break down phenylalanine.

Typically, when phenylalanine is broken down, it produces melanin as a by-product. Melanin is a pigment that’s responsible for giving the skin and eyes their distinct colour. 

When there’s a short supply of this pigment in the body, it’ll result in the body having lighter skin and blue eyes. This may resemble the characteristics of albinism.

Besides the physical changes, patients are more likely to be diagnosed with skin diseases like eczema.

2) Musty Skin Odour

Does the patient have an unusual musty odour whenever you’re near them? This is a symptom of PKU, and it’s caused by the build-up of the amino acid phenylalanine in the body.

The musty odour can be described as mouse-like and often affects the person’s skin and urine. It also intensifies when a patient becomes sweaty.

3) Behavioural and Intellectual Problems

Does the patient frequently show their moody side? Do they struggle at school? Are they unable to form social connections with their peers?

If so, these could be signs that they’re suffering from PKU. When the blood count levels of phenylalanine are too high, this can enter the cranial region and poison the brain. This, in turn, causes a range of mental health issues.

If left untreated, this can cause permanent mental retardation and the inability to form relationships with others. If the patient has shown these signs of intellectual and behavioural problems, they may be unable to fully recover at that point.

4) Seizures and Tremors

Neurological episodes like seizures are common among PKU sufferers, affecting approximately 50% of all the people diagnosed with the condition.

Typically, phenylalanine breaks down into by-products, one of which is tyrosine. When the body is deficient in tyrosine, it can cause neurological problems like seizures and involuntary shaking.

Management of PKU

Managing PKU is doable, and patients can live a healthy life despite the condition.

Here are some lifestyle modifications and treatment plans that are prescribed to people with PKU.

• Partake in a low-protein diet
• Take the FDA-approved Sapropterin
• Avoid foods with aspartame

Through these steps, sufferers can continue to live healthy lives even with the condition. Besides maintenance, it’s important to regularly meet with your doctor to ensure that you’re on track with your health journey.