Early serum alkaline phosphatase and other factors associated with enteral feeding in very low birth weight preterm infants.

Objectives: Alkaline phosphatase (ALP), particularly the intestinal isoform, plays an important role in gut maturation and function. This study evaluated the relationship between early serum ALP levels and time to full enteral feeding (FEF) in very low birth weight (VLBW) preterm infants, hypothesizing that ALP levels at 48 h could predict feeding advancement.

Methods: This retrospective cohort study included 437 VLBW preterm infants admitted to the NICU at Meir Medical Center from 2014 to 2022.

Results: Infants who achieved FEF within 10 days (early FEF) had higher median ALP levels at 48 h than those requiring >10 days (late FEF) (265 U/L vs. 244 U/L, respectively; p = 0.035). However, multivariate analysis showed ALP levels were not a significant predictor of delayed FEF (odds ratio [OR] = 0.97, p = 0.063), and receiver operating characteristic analysis indicated poor predictive value (area under the curve = 0.547, p = 0.088). Low ALP levels were associated with early-onset sepsis, amnionitis, and lower birth weight (BW) Z-scores. Factors associated with prolonged FEF included younger gestational age, lower serum phosphorus levels, respiratory support, and lower BW Z-scores.

Conclusion: Early serum ALP levels are linked to neonatal comorbidities but are not reliable predictors of time to FEF in VLBW preterm infants. Further studies are needed to explore the clinical relevance of ALP levels in this population.