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Prevalence and long-term course of macro-aspartate aminotransferase in children

Maria Caropreso1, Giuliana Fortunato, Selvaggia Lenta

  • 1Department of Pediatrics, University of Naples Federico II, Naples, Italy.

The Journal of Pediatrics
|December 30, 2008
PubMed

Insights

Macro-aspartate aminotransferase (macro-AST) was found in over a third of children with elevated AST. This condition appears benign in childhood, with macro-AST often persisting long-term.

Area of Science:

  • Clinical Biochemistry
  • Pediatric Gastroenterology

Background:

  • Elevated aspartate aminotransferase (AST) levels in children can be a diagnostic challenge.
  • Macro-aspartate aminotransferase (macro-AST), a complex of AST with other molecules, can cause persistent AST elevation.
  • Understanding the prevalence and clinical significance of macro-AST in pediatric populations is crucial.

Purpose of the Study:

  • To determine the prevalence of macro-AST in children with isolated elevated AST.
  • To investigate the association of macro-AST with clinical conditions.
  • To evaluate the long-term clinical and laboratory course of macro-AST in children.

Main Methods:

  • Screening of 44 children with isolated elevated serum AST for macro-AST using electrophoresis and % polyethylene glycol (PEG) precipitable activity (PPA).
  • Clinical and laboratory follow-up for up to 16 years.
  • Analysis of AST levels and macro-AST persistence over time.

Main Results:

  • Macro-AST was identified in 38.6% of the children studied.
  • Children with macro-AST had significantly higher AST values compared to those without.
  • Macro-AST persisted in most positive cases over long-term follow-up, while AST levels normalized in macro-AST-negative children.

Conclusions:

  • Macro-AST is a common finding in children with isolated AST elevation and appears to be a benign phenomenon.
  • Established %PPA thresholds can serve as an effective screening tool for macro-AST.
  • Electrophoresis is recommended for confirmation and in cases with intermediate %PPA results.
Abstract

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