Background: Fecal calprotectin has been proposed as a non-invasive marker of intestinal inflammation in inflammatory bowel disease in adults and children. Fecal calprotectin levels have been reported to be much higher in both healthy full-term and preterm infants than in children and adults.
Objective: To determine the time course of fecal calprotectin (f-calprotectin) excretion in preterm infants from birth until hospital discharge and to identify factors influencing f-calprotectin levels in the first weeks of life, including bacterial establishment in the gut.
Methodology: F-calprotectin was determined using an ELISA assay in 147 samples obtained prospectively from 47 preterm infants (gestational age, and birth-weight interquartiles 27-29 weeks, and 880-1320 g, respectively) at birth, and at 2-week intervals until hospital discharge.
Principal findings: Although median f-calprotectin excretion was 138 microg/g, a wide range of inter- and intra-individual variation in f-calprotectin values (from day 3 to day 78) was observed (86% and 67%, respectively). In multivariate regression analysis, f-calprotectin correlated negatively with ante and per natal antibiotic treatment (p = 0.001), and correlated positively with the volume of enteral feeding (mL/kg/d) (p = 0.009), the need to interrupt enteral feeding (p = 0.001), and prominent gastrointestinal colonization by Clostridium sp (p = 0.019) and Staphylococcus sp (p = 0.047).
Conclusion: During the first weeks of life, the high f-calprotectin values observed in preterm infants could be linked to the gut bacterial establishment.