Plasma fatty acid composition and lipid peroxide levels in children with paucity of interlobular bile ducts.

The total and free fatty acid composition of plasma and lipid peroxide concentrations was studied in 32 cholestatic children with syndromatic paucity of interlobular bile ducts (Alagille's syndrome). The mean lipid peroxide value in these patients was 8.80 +/- 3.70 nmol/ml, nearly 4 times higher than the mean control value. Compared to the control group, the patients exhibited significant variations in total fatty acids, and in particular a relative decrease in linoleic acid (from 29.5 +/- 6.1% in the controls to 19.1 +/- 8.03% in the patients) compensated by an increase in saturated and monounsaturated fatty acids. The plasma lipid peroxide levels were inversely correlated with the unsaturated/saturated fatty acids ratio in total fatty acids, and with the vitamin E status (vitamin E/total lipids). Most of the total and free fatty acid variations observed were largest in patients with severe jaundice. Dietary fat malabsorption and the increase in lipid peroxidation partly explain these results. Furthermore, in free fatty acids, we observed a marked increase in arachidonic acid (from 1.43 +/- 0.85% in the controls to 4.27 +/- 2.24% in the patients), suggesting abnormal eicosanoid synthesis.

[Identification and assay of nonvolatile organic by capillary column gas chromatography]. / Identification et dosage des acides organiques non volatils par chromatographie en phase gazeuse sur colonne capillaire.

The assay of organic acids as trimethyl silyl isobutyl compounds by gas chromatography was described. The lyophilization was used instead the extraction by organic reagent of the classical methods. Our method avoids the loss of some hydroxylacids. The identification and the measurement of one organic acid need respectively 3 and 5 hours. Our method is currently used for the metabolic diseases diagnosis.