Serum intestinal fatty acid binding protein is elevated during feeding advancement in necrotizing enterocolitis

In retrospective studies, intestinal fatty acid binding protein (I-FABP) has been suggested as a potential biomarker to identify NEC prior to clinical diagnosis. We hypothesize that increasing I-FABP levels with feeding advancement may be a biomarker of intestinal stress prior to clinical suspicion of NEC.

Prospective study of neonates ≤ 32-week gestation and ≤1500 grams enrolled within 72 h of life. Blood was obtained for biomarker assessment with feeding advancement. ELISA was used to assay serum I-FABP (sI-FABP).

Of 96 patients enrolled, 9 were diagnosed with NEC. sI-FABP values remained low in healthy controls and NEC patients at the initial stages of feeding, up to 60 mL/kg/day. In those who developed NEC, there was a significantly higher sI-FABP at the final sample compared to their own earlier samples (p < 0.0001) or matched controls (p < 0.001). Those who developed NEC while feed volumes were being increased had a significantly higher sI-FABP than others. Receiver operating characteristic (ROC) curve analysis identified sI-FABP of 4.8 ng/mL to be predictive of early NEC with 80% sensitivity and 100% specificity (AUC 0.92; p < 0.01).

Elevation in sI-FABP with increasing volume of enteral feeds correlates with, and precedes, clinical suspicion of NEC.

Serum intestinal fatty acid binding protein elevation during feeding advancement is a sensitive and specific biomarker for necrotizing enterocolitis that precedes clinical suspicion. Early and accurate identification of infants at risk for necrotizing enterocolitis prior to development of symptoms allows the identification of patients at risk that may benefit from early intervention or trial of potential therapies.