Galactose oxidation using (13)C in healthy and galactosemic children.

Abstract

Galactosemia is an inborn error of galactose metabolism that occurs mainly as the outcome of galactose-1-phosphate uridyltransferase (GALT) deficiency. The ability to assess galactose oxidation following administration of a galactose-labeled isotope (1-(13)C-galactose) allows the determination of galactose metabolism in a practical manner. We aimed to assess the level of galactose oxidation in both healthy and galactosemic Brazilian children. Twenty-one healthy children and seven children with galactosemia ranging from 1 to 7 years of age were studied. A breath test was used to quantitate (13)CO2 enrichment in exhaled air before and at 30, 60, and 120 min after the oral administration of 7 mg/kg of an aqueous solution of 1-(13)C-galactose to all children. The molar ratios of (13)CO2 and (12)CO2 were quantified by the mass/charge ratio (m/z) of stable isotopes in each air sample by gas-isotope-ratio mass spectrometry. In sick children, the cumulative percentage of (13)C from labeled galactose (CUMPCD) in the exhaled air ranged from 0.03% at 30 min to 1.67% at 120 min. In contrast, healthy subjects showed a much broader range in CUMPCD, with values from 0.4% at 30 min to 5.58% at 120 min. The study found a significant difference in galactose oxidation between children with and without galactosemia, demonstrating that the breath test is useful in discriminating children with GALT deficiencies.

• Authors: D R Resende-Campanholi, G Porta, E Ferrioli, K Pfrimer, L A Del Ciampo, J S Camelo Junior
• Journal: Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas (Braz J Med Biol Res) Vol. 48 Issue 3 Pg. 280-5 (Mar 2015) ISSN: 1414-431X [Electronic] Brazil
• PMID: 25608239 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• UTP-Hexose-1-Phosphate Uridylyltransferase
• Galactose

Topics

• Breath Tests
• Case-Control Studies
• Child
• Child, Preschool
• Female
• Galactose (metabolism)
• Galactosemias (genetics, metabolism)
• Humans
• Infant
• Male
• Mass Spectrometry
• Oxidation-Reduction
• ROC Curve
• UTP-Hexose-1-Phosphate Uridylyltransferase (genetics, metabolism)