Neonatal gut function, measured by the one hour blood D (+) xylose test: influence of gestational age and size

Area of Science:

• Neonatal physiology
• Gastrointestinal development
• Nutritional science

Background:

• Assessing D(+) xylose absorption is crucial for understanding neonatal gastrointestinal function.
• Infant growth parameters, including gestational age and size, can influence nutrient absorption.
• Perinatal intestinal maturation is a key developmental process.

Purpose of the Study:

• To evaluate D(+) xylose absorption in neonates of varying gestational ages and sizes.
• To investigate the impact of intrauterine growth retardation on intestinal absorption.
• To determine if intestinal absorption improves over the early neonatal period.

Main Methods:

• D(+) xylose absorption was measured via one-hour blood xylose levels after intraduodenal infusion.
• The study included 35 infants of differing gestational ages and sizes, tested between days 2 and 6 of life.
• Serial absorption studies were conducted on 11 infants multiple times between days 3 and 20.

Main Results:

• Full-term, appropriately grown infants exhibited higher blood xylose levels than preterm or 'light for dates' infants.
• Infants with intrauterine growth retardation showed the least increase in xylose absorption over time.
• No catch-up growth in absorption was observed in the 'light for dates' group; some showed declining absorption relative to controls.

Conclusions:

• The small intestine demonstrates maturation during the perinatal period.
• Intrauterine growth retardation appears to negatively impact intestinal absorptive capacity in neonates.
• The long-term nutritional implications of impaired neonatal intestinal absorption require further investigation.