American Journal of Clinical Nutrition, Vol 27, 777-787, Copyright © 1974 by The American Society for Clinical Nutrition, Inc.

Luminal events of lipid absorption in protein-calorie malnourished children; relationship with nutritional recovery and diarrhea. I. Capacity of the duodenal content to achieve micellar solubilization of lipids

¹ Chief, Gastrointestinal Section, Biomedical Division, Institute of Nutrition of Central America and Panama (INCAP), Carretera Roosevelt, Zone 11, Guatemala City, Guatemala, C.A.
² Head, Biomedical Division of INCAP

Fat absorption and the capacity of the duodenal content to achieve micellar solubilization of lipids were studied longitudinally in 18 severely protein-calorie malnourished (PCM) children on admission and at different stages of nutritional recovery, as well as in the presence or absence of diarrhea. Four healthy children were studied as controls. It was found that micellar lipid (ML) and fat absorption were abnormally low in PCM children and that both improved, reaching normal values with nutritional recovery. Diarrhea hampered this improvement and was associated with larger amounts of duodenal aspirates in 90 min and higher dilution of the emulsion. Stepwise regression analysis revealed that bile acids, especially conjugated bile acids (CBA) explained 44% of the variability in ML observed. Other factors such as pancreatic lipase activity and dilution played a minimal role in explaining such variability (8% and less than 1%, respectively). Increased concentrations of free bile acids (FBA) were also observed in all patients, regardless of nutritional status. Although ML rose as CBA concentration increased, a discrete but opposite trend was observed with FBA. ML decreased almost exponentially as the FBA/CBA ratio increased. We concluded that a decrease in CBA and an elevation in the FBA/CBA ratio played an important role in decreasing micellar lipid capacity and lipid absorption in children suffering from PCM or diarrhea.