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Performance of children with phenylketonuria in the Developmental Screening Test--Denver II
Greyce Kelly da Silva1, Dionísia Aparecida Cusin Lamônica
1Fonoaudióloga, Faculdade de Odontologia, Universidade de São Paulo de Bauru (FOB/USP), Brazil. greycefono@uol.com.br
Background:
phenylketonuria is an autosomal recessive disorder resulting from the mutation of a gene located in chromosome 12q22-24.1.
Aim:
to describe the performance of children with classic phenylketonuria, who were diagnosed and treated early, in the Development Screening Test Denver - II.
Method:
participants were 20 children with phenylketonuria, ranging in age from 3 and 6 years, and 10 children with typical language development, paired by gender, age and socioeconomic level to the research group. The plasmatic phenylalanine measure and the neurological, psychological and social information were gathered in the data base of the Neonatal Screening Programs for Metabolic disorder. Assessment consisted on the application of the Development Screening Test Denver II. A descriptive statistical analysis and the Mann Whitney test were used in order to characterize the tested skills. For the measurements of the plasmatic phenylalanine blood levels the values considered for analysis were: below 2 mg/dL, above 4 mg/dL, reference values between 2 and 4 mg/dL, of all exams performed during the participants'lives; maximum and minimum values and values obtained on the day of the screening application.
Results:
comparison between the groups indicated statistically significant differences for the personal-social and language areas.
Conclusion:
children who were diagnosed and treated early for phenylketonuria present deficits in the personal-social and language areas. Also, even when receiving follow-up and undergoing treatment, these children presented difficulties in maintaining normal plasmatic phenylalanine levels.
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