Urinary Intestinal Fatty Acid Binding Protein “IFABP” as a Marker for Gut Maturation in Preterm Babies

Objective: Formula-fed premature babies have a higher incidence of developing necrotizing enterocolitis (NEC) than breast-fed babies which may be caused by breast milk induced gut maturation. The effect of breast milk on maturation of the gut has been widely studied in animal models and recently in humans.

The aim of this study is to evaluate the effects of breast-feeding on maturation of the intestine in premature babies by measuring the postnatal values of a specific enterocyte marker which is urinary intestinal fatty acid binding protein (I-FABP).

Method: Maturation of the gut was studied in 60 premature babies (<37 weeks of gestation) without gastrointestinal morbidity. 30 of them were exclusively breast-fed and the other 30 were formula-fed. Urinary I-FABP levels as the measure of gut maturation were measured at 7^th, 12^th, and 22^nd post-natal days.

Results: In breast-fed babies, there was a statistically significant increase in urinary I-FABP levels between 7^th and 12^th days after birth compared with formula-fed babies (p<0.01)

Conclusions: The pattern of postnatal changes in urinary I-FABP levels suggests a delayed physiological response causing significantly delayed gut maturation in formula-fed babies compared with breast-fed ones.