Sterols profiling in red blood cell membranes and plasma of newborns receiving total parenteral nutrition.

Background and Objectives: Total parenteral nutrition (TPN) is a lifesaving therapy in children with intestinal failure, frequently complicated by liver dysfunction. Plant sterols (phytosterols) of lipid emulsions have been supposed to contribute to cholestasis in TPN-treated children. The present study aimed to evaluate the plasma and red blood cell membrane (RBCM) phytosterol levels in newborns after a short period of TPN. Patients and Methods: Phytosterols, cholesterol, and other sterol levels were quantified by gas chromatography-mass spectrometry in 15 healthy control infants, 22 patients after TPN, and 11 patients before TPN. Sterols of lipid emulsions were quantified. Results: Plasma and RBCM phytosterol levels were, respectively, on average 56mmol/L and 83mmol/g per protein in patients after TPN, 13mmol/L and 15mmol/g per protein in patients before TPN, and 9mmol/L and 13mmoL/g per protein in control infants (P<0.05 for differences). The days of TPN and the total amount of infused lipids correlated significantly with RBCM phytosterol (P<0.05); correlations for plasma were positive but not significant. No correlation was observed with plasma bilirubin, g-glutamyltransferase, or alanine transaminase. Conclusions: Plasma and RBCM phytosterols increase significantly in newborns after a short period of TPN. Higher phytosterol levels were observed in some patients that could have been due to their individual variability in phytosterol metabolism and/or clearance. A greater accumulation of phytosterols in membranes may induce TPN-related cholestasis.