P875 Faecal Calprotectin (FC) in Babies Born to Mothers with or Without IBD and Correlation with Microbiome

There is an increased risk of IBD in children born to mothers with IBD. We previously showed that babies born to IBD mothers had evidence of gut microbiota dysbiosis at birth that persisted up to 3 months of life. Herein, we investigated FC concentrations as a biomarker of gut inflammation in babies born to mothers with or without IBD during their first year of life, participating in the MECONIUM (Exploring MEChanisms Of disease traNsmission In Utero through the Microbiome) study. 243 infant stool samples obtained at 2 weeks (2w), 2 months (2m) and 1 year (1y) from 122 babies (33 born to mothers with IBD) were analysed using a quantitative enzyme immunoassay (CalproLabTM Calprotectin ELISA, Norway). Maternal IBD status was collected prospectively and we included 97 mother-baby pairs at 2w, 96 at 2m and 28 at 1y. FC concentrations were compared by maternal IBD status, and then correlated with the infant microbiome composition at 2w and 2m. Statistical analyses were performed with Graph Pad Prism 7.0 and R software. Overall, FC levels in babies were higher than the levels observed in healthy adults and decreased with age (median FC 497 µg/g [interquartile, IQR: 253–766] at 2w vs. 170 µg/g [IQR: 45–327] at 1y; p < 0.0001). No significant difference in FC levels was detected in babies born to mothers with IBD compared with those with no IBD at any time point. However, babies born to mothers with active disease during pregnancy sustained higher FC levels at 1y (median FC=502 µg/g) as compared with those born to mothers in remission (median FC=141 µg/g; p = 0.17), or with no IBD (median FC=124 µg/g; p = 0.016, Figure 1). FC levels across all time points correlated with relative abundance of Gammaproteobacteria (r=0.39; p = 0.0002). Fecal Calprotectin concentrations in babies at 2 weeks, 2 months and 1 year according to maternal IBD status (control, remission or active). Newborns had high levels of FC that decreased with age. Babies born to mothers with active IBD during pregnancy displayed higher FC levels at 1 year of life compared with babies not exposed to IBD in utero. FC levels also correlated with more pro-inflammatory bacterial profiles in early life. If confirmed in a larger sample size, these results may suggest evidence of early subclinical inflammation of which duration and consequences need to be further investigated.