ACTIVITIES OF TRYPSIN AND LIPASE IN DUODENAL ASPIRATES OF HEALTHY PRETERM INFANTS - EFFECTS OF GESTATIONAL AND POSTNATAL AGE

Lipase and trypsin activities were estimated in preprandially aspirate d duodenal juice of preterm infants with gestational ages between 29 a nd 32 weeks (group I, n = 33) or between 33 and 36 weeks (group II, n = 22) during the first 6 weeks of postnatal life. The results were com pared with the enzyme activities measured in 2- to 6-year-old children . There were no significant differences of the mean lipase or trypsin activities between the two groups (lipase; group I 13.7 +/- 7.9, group II 15.9 +/- 9.8 U/ml; trypsin: group I 7.9 +/- 4.7, group II 8.5 +/- 5.1 U/ml). The activities of both enzymes increased significantly and similarly in both groups with postnatal age (lipase: group I r = 0.732 , p < 0.01, group II r = 0.743, p < 0.01; trypsin: group I r = 0.705, p < 0.01, group II r = 0.669, p < 0.01). At the end of the study the l ipase activities of both groups reached approximately 35% of the value s found in the older children, whereas the trypsin activities reached the reference values within the 1st month of life. The results indicat e an asynchronously age-related development of lipase and trypsin. The development of the lipase activity is delayed in comparison to the tr ypsin activity which should be considered in the nutritional managemen t of preterm infants.