[The effect of the lipid emulsions used in parenteral nutrition on the immune response capacity].

The preservation or improvement of the immune response capacity in patients on TPN is a priority objective, since in this type of patient, immune deficiencies caused by the main illness, malnutrition or the therapy applied are constant and reflected in the great incidence of septic complications. The use of lipid emulsions in TPN has an obvious clinical repercussion in this respect, due to the intake of EFA (eicosanoid precursors) and the possible negative effect suggested in some studies on the reticulo-endothelium system and other immune functions. This review analyzes the effect of lipid emulsions used in TPN on the immune system. For this purpose, studies on the effect of MCT/LCT an LCT emulsions on the phagocytic and chemotactic functions have been evaluated; antigenic presentation; synthesis of Igs and complement fractions; cellular differentiation and activation; helper or suppressing functions, etc. From the studies reviewed, it can be deduced that there is no clinical evidence of a negative effect caused by lipids when administered in the recommended dosage, whereas an improvement is noted in the immune response capacity, on reverting the nutrition. From comparative studies aimed at evaluating the effect of LCT and MCT/LCT on the different components of the immune system, favourable results have been achieved using the MCT/LCT emulsion, although it is early to say that this will lead to significant clinical repercussions.