Evaluation of pancreatic function development after hydrolyzed protein-based and soy-based formulas in unweaned infants

Aims: Different protein sources could determine differences in the maturation of the exocrine pancreas in humans during the first months after birth; however, no studies have been carried out in man to evaluate the effect of a hydrolyzed protein diet on exopancreatic function. Our aim was therefore to determine the effect of two different milk formulas on pancreatic secretion in patients with cow's milk protein allergy (CMPA). Methods: We selected 12 infants (median age, 3.0 months), fed for 6 weeks with a hydrolyzed casein-based formula, and 14 infants (median age, 3.0 months) who received a soy-protein based formula over the same period. As controls, two groups of age-matched infants with no gastrointestinal disease and receiving a free diet were studied. In the patients with CMPA a secretin-cerulein test was performed at the commencement of the diet and after 6 weeks; in the controls the same test was performed only once. Enzyme concentrations and outputs of trypsin, chymotrypsin, lipase, and phospholipase were assayed. Results: No significant difference was observed between the two groups of patients with CMPA for any of the enzymes studied, either at base line or after 6 weeks of diet. No difference was recorded between CMPA patients and age-matched controls on a free diet either. In both CMPA groups there was a significant increase over basal values in trypsin, chymotrypsin, and lipase concentrations after 6 weeks. Furthermore, there was a significant positive correlation between the age of the patients and enzyme concentrations. Mean daily weight gain was 27.4 +/- 3.9 g with hydrolyzed casein and 27.2 +/- 3.5 g in soy fed patients. Conclusions: It is suggested that the diets with different protein content used in subjects with CMPA did not determine any difference in the stimulation of proteolytic and lipolytic pancreatic enzymes.