A study of fat absorption in cystic fibrosis patients and controls by a rapid micro procedure: a comparison with fecal fat excretion method.

Fat absorption was studied in 11 Cystic Fibrosis patients and 6 controls by measuring a) fecal fat excretion and b) serum turbidity using a nephelometer between 0 and 2 hours after a butter-fat load. Cystic Fibrosis patients showed a mean +/- SEM fecal fat excretion of 21.6 +/- 5.5%, and controls a mean of 2.7 +/- 0.45%, of the dietary fat. The turbidity change expressed as delta turbidity showed a mean value of 1.37 +/- 0.57 in Cystic Fibrosis patients and 31.8 +/- 5.7 in controls. Fecal fat excretion method showed a good negative correlation with the butter fat method. The butter fat absorption method was also compared with fecal fat excretion in rats with induced malabsorption and control rats. The results obtained were comparable to those in the patients. The method described here is rapid and can be performed with small blood volumes and therefore may be suitable to study fat malabsorption in pediatric patients.