PP-107 Serum neuropeptides and intestinal microbiota composition in children with allergy

Aim To determine associations between the intestinal microbiota composition and the levels of neuropeptides in children with allergy in the period of nutrition diversification. Material and Method This is a cross-sectional, single-center study of 90 children with food allergy in groups: 6–12 (I, n=56) and 13–18 months old (II, n=34). The levels of neuropeptides in blood serum were studied by the ELISA method; the intestinal microbiota composition - by bacteriological method. Results Complementary foods were introduced to children of both groups at the age of 5.5 [5–6] months old. At 13–18 months children received 10–12 groups of products. In group I, the neuropeptides` content was Me [IQR]: Beta-NGF – 10.0[6.85–278], NT-3 – 4,1[3–4,1], NT-4 – 20,9[1,3–104]pg/ml, SYP – 0,12[0–0,2], NR2AT – 0.5[0.21–0.7]ng/ml. The reduced content of intestinal bacteria genus was found: Bifidobacterium in 19%, Lactobacillus in 43%, E. coli Lac (+) in 21%; increased: Clostridium in 41%, Proteus in 98%, Klebsiella in 34%, Pseudomonas in 96%. In group II, the neuropeptides` content was Me [IQR]: Beta-NGF – 236.2[15.0–1326], NT-3 – 4,1[3–242,1], NT-4 – 44,0[1,3–275,5]pg/ml, SYP – 0,12[0–0,31], NR2AT – 0.69[0.40–1.2]ng/ml. The reduced content of intestinal bacteria genus was noted: Bifidobacterium in 73%, Lactobacillus in 21%, E. coli Lac (+) in 35%; increased: Clostridium in 76%, Proteus in 94%, Klebsiella in 21%, Pseudomonas in 94%. The following correlations were revealed: positive – Proteus spp & Beta-NGF, NT3, NR2AT (R= 0.247, 0.221, 0.226), E. coli Lac (+) & SYP (R=- 0.257), Hafnia spp & SYP (R=0.30), Providencia spp & SYP (R=0.30), Lactobacillus spp & NR2AT (R=0.216), Acinetobacter spp & Beta-NGF, NT-4, NR2AT (R=0.249, 0.234, 0.348). Conclusions We revealed bidirectional connections between the serum neuropeptides and some indicators of the intestinal microbiota in children with allergy in the period of nutrition diversification. The role of these associations in the formation of the 'gut -brain' axis requires further study.