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What is One year old male child with sparse blond hair, developmental delay and tremors, diagnosis and explain in detail?
Phenylketonuria is due to deficiency of enzyme phenylalanine hydroxylase or of its cofactor tetrahydrobiopterin ;leads to accumulation of phenylalanine in body fluids and brain. It is mainly characterized by profound mental retardation ,lighter complexion and neurologic symptoms like tremors,hyperreflexia and spasticity. Reference: Nelson TB of pediatrics 19th edition, pg 418