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Intellectual, adaptive, and behavioral functioning in children with urea cycle disorders

Lauren Krivitzky1, Talin Babikian, Hye-Seung Lee

  • 1Department of Psychiatry and Behavioral Sciences, George Washington University School of Medicine and Health Sciences, Washington, DC 20010, USA. lkrivitz@cnmc.org

Pediatric Research
|March 17, 2009
PubMed

Insights

Children with urea cycle disorders (UCDs) face significant neurodevelopmental challenges. Neonatal onset UCDs are linked to worse cognitive and adaptive outcomes, including intellectual disability, compared to later onset forms.

Area of Science:

  • Biochemistry
  • Genetics
  • Neuroscience

Background:

  • Inborn errors of urea synthesis cause ammonia accumulation, leading to mortality and neurodevelopmental disability.
  • Urea cycle disorders (UCDs) represent a spectrum of genetic conditions affecting ammonia detoxification.
  • Understanding the long-term functional outcomes in children with UCDs is crucial for effective management.

Purpose of the Study:

  • To characterize cognitive, adaptive, and emotional/behavioral functioning in children with UCDs.
  • To compare outcomes between neonatal onset (NO) and late onset (LO) UCD presentations.
  • To identify specific neurocognitive and behavioral challenges associated with UCDs.

Main Methods:

  • Cognitive, adaptive, and emotional/behavioral domains were assessed in 92 children with UCDs.
  • Data collection involved standardized testing and parent-reported questionnaires.
  • Participants were stratified into neonatal onset (n=33) and late onset (n=59) groups.

Main Results:

  • Children with neonatal onset UCDs exhibited poorer outcomes than those with late onset UCDs.
  • Approximately 50% of neonatal onset cases presented with intellectual disability (ID), with 30% severely impaired.
  • Late onset UCDs also showed impairments, particularly in attention and executive functions, with about 25% in the ID range.

Conclusions:

  • UCDs result in a wide spectrum of cognitive and functional outcomes.
  • Neonatal onset UCDs carry a significantly higher risk of intellectual disability, which may worsen with age.
  • Even late onset UCDs are associated with neurocognitive and behavioral deficits, impacting executive functions and attention.

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