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Examining the blood amino acid status in pretherapeutic patients with  hyperphenylalaninemia

Lili Liang1, Jun Ye1, Lianshu Han1

  • 1Department of Pediatric Endocrinology/Genetics, Shanghai Institute for Pediatric Research, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Journal of Clinical Laboratory Analysis
|November 26, 2019
PubMed

Insights

Hyperphenylalaninemia, a common genetic disorder, shows distinct amino acid profiles in patients before treatment. Early detection and understanding these metabolic differences are crucial for preventing brain damage.

Area of Science:

  • Biochemistry
  • Genetics
  • Pediatrics

Background:

  • Hyperphenylalaninemia is the most common genetic metabolic disease.
  • Early intervention is critical to prevent neurological damage.
  • Understanding pre-treatment amino acid status is key for effective management.

Purpose of the Study:

  • To determine the precise amino acid profiles of hyperphenylalaninemia patients before initiating treatment.
  • To compare amino acid levels in newborns and older patients with healthy controls.

Main Methods:

  • Collected blood samples from 116 newborns and 161 older hyperphenylalaninemia patients.
  • Analyzed 17 amino acids using tandem mass spectrometry.
  • Compared patient data with normal controls and analyzed phenylalanine correlations.

Main Results:

  • Patients exhibited significantly different amino acid levels compared to controls, including altered phenylalanine, valine, tyrosine, and threonine.
  • Newborns and older patients showed unique patterns of amino acid deviations.
  • Nonlinear correlations and threshold effects were observed between phenylalanine and other amino acids like tyrosine and threonine.

Conclusions:

  • Pre-treatment hyperphenylalaninemia patients display a significantly altered amino acid status compared to healthy individuals.
  • Specific amino acids demonstrate nonlinear relationships with phenylalanine levels, exhibiting threshold effects.
Abstract

Keywords:
amino acidshyperphenylalaninemianewborn screeningphenylalanine hydroxylase deficiencyphenylketonuria

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