Galactose oxidation using 13C in healthy and galactosemic children

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 (1-13C-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 13CO2 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 1-13C-galactose to all children. The molar ratios of 13CO2 and 12CO2 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 13C 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.

Lipoidoproteinose-hialinose mucocutânea: doença de Urbach-Wiethe; apresentaçäo de um caso e revisäo da literatura / Lipoidproteinosis-hyalinosis mucocutaneous: disease of Urbach-Wiethe: report of a case and review of literature

Os autores fazem a revisäo bibliográfica e apresentam um caso de Lipoidoproteinose, ou hialinose cutâneo-mucosa ou Doença de Urbach-Wiethe. Trata-se de uma doença rara, que ocorre por acumulo de material hialino de natureza bioquímica desconhecida, nas mucosas, pele, trato aéreo digestivo alto, sistema nervoso central, e em outros tecidos. Säo descritos as manifestaçöes e os achados clínicos gerais e otorrinolaringológicos, os exames complementares, bem como a evoluçäo clínica. Pela raridade e gravidade da doença que näo tende a regredir seja espontaneamente ou com tratamento, levando ao êxito letal, o otorrinolaringologista deve ter conhecimento prévio desta doença