Giovannini M, Fiori L, Agostoni C, Colombo L, Verduci E, Giannií» ML, Riva E

Department of Pediatrics, San Paolo Hospital, I-20142 Milan, Italy


Background: Long-chain polyunsaturated fatty acid (LCPUFA) have relevant roles in growth and neural development. Phenylketonuric (PKU) children on dietary treatment are supplied with foods lacking LCPUFA. In a previous trial a balanced  supplementation with LCPUFA for one year restored physiological LCPUFA levels in blood in 10-year old PKU.

Aim: We have determined the LCPUFA status of PKU children who completed the previous trial three years after completion of the supplementation.

Subjects and methods: 20 dietary treated PKU (mean age 13.5 years), who had been randomized to receive a supplementation with 0.5 g fat caps/4 kg body weight, were sampled after an overnight fasting. Fat caps provided either 26% fatty acids (FA) as LCPUFA (18:3n-6 = 4.6%, 20:4n-6 = 7.4%, 20:5n-3 = 5.5%, 22:6n-3 = 8%) or olive oil (control group). The composition of FA methyl esters (wt%) of plasma total lipids, TL and lipid fractions (phospholipids, PL, cholesterol esters, CE, triglycerides, TG) has been measured with capillary gas-chromatography.

Statistics: non-parametric tests.

Results: The two groups did not differ for the major LCPUFA levels in plasma TL, CE and PL. A trend for higher levels of n-3 LCPUFA (20:5n-3 and 22:6n-3) was present in plasma TG of the supplemented group. In this group the 22:6n-3 levels in plasma PL three years before were associated with the actual 22:6n-3 levels in plasma TG (Rsq=0.41, P=0.03).

Conclusions: Since plasma PL reflect current dietary habits and fasting plasma TG are a partial marker of stored fats, a supplementation with LCPUFA may have a long-term effect in treated PKU.