Question
Phenylketonuria is a genetic disorder that can occur even if there is no history of the condition in the family. For a one-and-a-half-month-old infant, can this condition be observed visually? If the baby is currently lively, does this mean there is no such condition?
Answer
The symptoms of phenylketonuria primarily manifest as intellectual development delay, with infants potentially showing an IQ lower than that of normal infants at 4 to 9 months of age. Severe patients may have an IQ below 50, with particularly pronounced language development disorders. In addition, patients may experience neurological and psychiatric manifestations such as cerebellar malformations due to brain atrophy, recurrent seizures, increased muscle tone, and hyperreflexia. Although the baby is currently lively, this does not rule out the possibility of phenylketonuria. It is recommended to undergo a professional medical examination for diagnosis.