Two cases of late-diagnosed phenylketonuria with autistic spectrum disorder in childhood
Main Article Content
Abstract
Phenylketonuria (PKU) is an autosomal recessive disorder with a carrier frequency of approximately 1/60 in Vietnam. Without early detection and treatment, it can lead to neurological developmental disorders such as epilepsy, intellectual disability (ID), and, in some cases, autism spectrum disorder (ASD). We present two cases: an 8-year-old boy diagnosed with ASD at age 3, whose condition did not improve with intervention, and a 10-year-old girl with a history of ASD and ID since 30 months of age. Both children were referred to the Center of Clinical Genetics, Hanoi Medical University, during genetic counseling for their pregnant mothers . Clinical examination, amino acid quantification, and whole-exome sequencing identified a pathogenic variant in the PAH gene, confirming a diagnosis of classic PKU. These case reports highlighted the importance of considering phenylalanine metabolism disorders in the differential diagnosis of children with ASD in clinical practice.
Article Details
Keywords
Phenylketonuria, autism spectrum disorder, genetic counseling, prenatal diagnosis, newborn screening
References
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