Amylin peptide is increased in preterm neonates with feed intolerance.

BACKGROUND: Amylin, a 37-amino-acid peptide hormone, is a potent inhibitor of gastric emptying. It is co-secreted by the pancreatic beta cells in response to enteral nutrient intake. Feed intolerance is common in preterm neonates and often presents as increased gastric residual volume (GRV). It is therefore hypothesised that serum amylin concentrations are raised in preterm neonates with poor gastric emptying, which may contribute to this observed feed intolerance. OBJECTIVE: To determine serum amylin concentrations in feed-intolerant preterm neonates. PATIENTS AND METHODS: Feed-intolerant (nTOL) preterm neonates (GRV >50% of a previous 4 h feed volume on two consecutive occasions) were matched for gestation, birth weight and postnatal age with feed-tolerant (TOL) neonates. Blood samples were analysed for amylin concentration. Seventy neonates were studied with median (interquartile range) gestation of 29 weeks (28-33) and birth weight of 1.3 kg (1.0-1.8). RESULTS: Serum amylin concentration and percentage GRV (median (interquartile range)) were significantly higher in the nTOL (47.9 pmol/l (21.4-79.8), 150% (100-350)) than the TOL (8.7 pmol/l (5.7-16), 5% (0-5)) group (p<0.001). In the nTOL group, a positive correlation was observed between serum amylin and GRV (r = 0.78, 95% CI 0.59 to 0.89, p<0.001), days to reach full enteral feeds (r = 0.40, 95% CI 0.08 to 0.68, p = 0.02), and days to discharge (r = 0.43, 95% CI 0.09 to 0.68, p = 0.01). CONCLUSIONS: Amylin may be responsible for delaying establishment of enteral nutrition in preterm neonates by virtue of its inhibitory effect on gastric emptying. Serum amylin concentrations in these neonates correlate with GRVs and time to reach full enteral feeds.

Amylin peptide levels are raised in infants of diabetic mothers.

BACKGROUND: Amylin is a novel 37 amino acid peptide hormone that is co-secreted with insulin from the pancreas in response to food intake. As a potent inhibitor of gastric emptying it plays an important role in the control of carbohydrate absorption. Feed intolerance is common in infants of diabetic mothers (IDM). AIMS: To establish a normal range of amylin levels in healthy neonates, and to determine whether serum amylin levels are raised in IDM. METHODS: A serial sample of 221 infants > or =28 weeks gestation was enrolled prior to delivery over a 12 month period. Blood samples collected immediately after birth (umbilical cord), and at the routine Guthrie test were analysed for amylin and insulin levels. RESULTS: Amylin levels in umbilical cord (n = 181) and Guthrie samples (n = 33) of healthy infants were 5.7 (3.0-9.1) and 6.9 (2.9-9.0) pmol/l respectively. IDM had significantly raised amylin levels in both cord (n = 31; 32.7 pmol/l, 25.9-48.1) and Guthrie samples (n = 8; 18.1 pmol/l, 15.3-23.6). Amylin correlated positively with insulin (n = 42; r = 0.67; 95% CI 0.4 to 0.81), birth weight (r = 0.22; 95% CI 0.08 to 0.36), and gestation (r = 0.18; 95% CI 0.03 to 0.32). Umbilical cord venous amylin levels showed agreement with arterial cord amylin levels (n = 34, mean bias -0.2, 95% CI 3.1 to -3.6). CONCLUSIONS: Amylin levels are significantly increased in the umbilical cord and Guthrie blood samples in IDM.