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Behavioral and intellectual functioning in patients with tyrosinemia type I

Monika Pohorecka1, Marta Biernacka, Anna Jakubowska-Winecka

  • 1Department of Pediatrics and Neonatology Central Clinical Hospital of Ministry of Internal Affairs, Warsaw, Poland. monika.pohorecka@cskmswia.pl

Pediatric Endocrinology, Diabetes, and Metabolism
|November 14, 2012
PubMed

Insights

In tyrosinemia type I, fluctuating tyrosine levels, not just high levels, are linked to attention deficits in children. Stabilizing tyrosine is key for improving focus and cognitive function during treatment.

Area of Science:

  • Biochemistry
  • Neuroscience
  • Pediatrics

Background:

  • Tyrosinemia type I (TT1) involves elevated tyrosine and phenylalanine, potentially impacting neurotransmitter synthesis and cognitive development in children.
  • Understanding the neurocognitive effects of TT1 is crucial for effective patient management.

Purpose of the Study:

  • To assess cognitive, emotional, and behavioral issues in children with TT1 undergoing treatment with a restricted diet and nitisinone.
  • To investigate the correlation between plasma tyrosine and phenylalanine levels and neurocognitive outcomes in TT1 patients.

Main Methods:

  • Analysis of cognitive development and behavior in eight TT1 patients over five years of nitisinone treatment.
  • Utilized the Wechsler Intelligence Scale for Children (WISC-R) and Child Behavior Checklist (CBCL/4-18) for psychological assessments.
  • Monitored plasma tyrosine and phenylalanine levels throughout the study period.

Main Results:

  • Attention deficits were observed in TT1 patients and may be associated with variations in plasma tyrosine levels.
  • A reverse correlation between attention deficit and verbal scale performance suggests potential difficulties in verbal reasoning and comprehension.
  • School difficulties were noted, possibly linked to attention and verbal processing challenges.

Conclusions:

  • The stability, rather than the absolute level, of tyrosine is significant for attention disorders and intellectual potential utilization in TT1.
  • Therapeutic strategies aimed at stabilizing tyrosine levels could help mitigate attention difficulties.
  • Adherence to a tyrosine-restricted diet is essential for maintaining normal tyrosine levels and supporting cognitive function.
Abstract

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