Uncover the five major symptoms of phenylketonuria

You may be familiar with phenylketonuria, but you may not know the root cause of this disease, what to pay attention to when you have this disease, and what symptoms you have. So, regarding these issues, I will reveal the five major symptoms of phenylketonuria for you below!

1. Typical PKU cases are mostly normal at birth. After 1 to 6 months, the infants gradually show a decrease in IQ, and become irritable, vomit, overactive or restless. Some infants develop eczema. Special odors such as mold or rat can be smelled on the body or clothes, which is a characteristic manifestation of children with this disease. Mental retardation is the most common symptom of this disease. About 90% of children may have moderate to severe mental retardation. After 6 months, the IQ drops rapidly, dropping to 50 at the age of 1, and to around 40 at the age of 3. When measured at the age of 5 to 6, the IQ score is usually less than 20, occasionally 20 to 50, and rarely greater than 50.

2. After the age of 1, the children's motor development is also significantly delayed, with language disorders being the most prominent. They may have clumsy gait, fine tremors in both hands, coordination disorders, strange postures, and repetitive finger gestures. Abnormal behavior is manifested as hyperactivity, irritability, agitated behavior, and emotional instability, which is seen in more than 60% of the children.

3. Epileptic seizures are another characteristic of this disease, which often occur around 1 year old. About 25% of children with severe mental retardation may have epileptic seizures. The most common clinical manifestation is flexor spasm, followed by absence seizures and generalized tonic-clonic seizures. Infantile spasms can also be seen. With age, infantile spasms decrease and turn into minor or major seizures.

4. Neurological physical examinations revealed few abnormalities. One third of the children were normal, and one third had mild hyperactivity, tremor, tendon hyperreflexia, ankle clonus, etc. Pyramidal signs were common. Involuntary movements such as torsion spasms, athetosis, dystonia, etc. and obvious cerebellar ataxia were also reported, but they were rare. Cerebral palsy may occur in severe cases.

5. Generally, the body shape and growth and development are normal. 90% of the children have melanin deficiency, and their skin is very white, but they are not albinos. Their hair is light yellow or brown, and their iris pigment is light brown-yellow, while that of Caucasians is blue. In addition, children may have sparse front teeth, cross-digital, and spina bifida. EEG examinations show abnormalities in 80% of cases. CT scans show brain atrophy.

Most of the symptoms and signs of acetonuria are reversible except for mental retardation. When the PA concentration is controlled, the symptoms can disappear, epilepsy can be controlled, EEG abnormalities can be restored, hair pigment can deepen, and body odor can disappear.